DNA fingerprinting test can do to identify and apprise about the genetic data’s in the human cells. This test very useful identify about family relationships between two peoples, identify real criminals and more. Genetic information’s is very unique data’s for deferent peoples. It’s like a physical fingerprint. That’s why called DNA fingerprinting to this test. To do this test, only need a very small sample of cells. For example it can do with a small blood drop or very small skin scrap. Also this test can do with single hair root.
How can we use DNA to solve some problems in our real life? This video lesion about that’s.
How your cell makes very important proteins - Part 4
Mutations in other body cells only cause trouble when they cause cancer or related diseases. Mutagens are chemical or physical agents that interact with DNA to cause mutations. Physical agents include high-energy radiation like X-rays and ultraviolet light. Chemical mutagens fall into several categories. Chemicals that are base analogues that may be substituted into DNA, but they pair incorrectly during DNA replication. Interference with DNA replication by inserting into DNA and distorting the double helix. Chemical changes in bases that change their pairing properties. Tests are often used as a preliminary screen of chemicals to identify those that may cause cancer. Most carcinogens are mutagenic and most mutagens are carcinogenic. Scientists have recognized a number of tumor viruses that cause cancer in various animals, including humans. About 15% of human cancers are caused by viral infections that disrupt normal control of cell division. All tumor viruses transform cells into cancer cells through the integration of viral nucleic acid into host cell DNA. Point mutations involve alterations in the structure or location of a single gene. Generally, only one or a few base pairs are involved. Point mutations can signficantly affect protein structure and function. Point mutations may be caused by physical damage to the DNA from radiation or chemicals, or may occur spontaneously. Point mutations are often caused by mutagens. The change of a single nucleotide in the DNA’s template strand leads to the production of an abnormal protein. Point mutations within a gene can be divided into two general categories. Base-pair substitutions - is the replacement of one nucleotide and its partner with another pair of nucleotides. Base-pair insertions or deletions - are additions or losses of nucleotide pairs in a gene.
How your cell makes very important proteins - Part 3
Universal: in all living organisms. A codon in messenger RNA is either translated into an amino acid or serves as a translational start/stop signal. Consists of a single RNA strand that is only about 80 nucleotides long. Each carries a specific amino acid on one end and has an anticodon on the other end. A special group of enzymes pairs up the proper tRNA molecules with their corresponding amino acids. tRNA brings the amino acids to the ribosomes, 3 dimensional tRNA molecule is roughly “L” shaped. Ribosomes facilitate the specific coupling of tRNA anticodons with mRNA codons during protein synthesis. The 2 ribosomal subunits are constructed of proteins and RNA molecules named ribosomal RNA or rRNA. The ribosome has three binding sites for tRNA. The P site, The A site, The E site. A specific enzyme called an aminoacyl-tRNA synthetase joins each amino acid to the correct tRNA. We can divide translation into three stages
• Initiation
• Elongation
• Termination
The AUG start codon is recognized by methionyl-tRNA or Met. Once the start codon has been identified, the ribosome incorporates amino acids into a polypeptide chain. RNA is decoded by tRNA (transfer RNA) molecules, which each transport specific amino acids to the growing chain. Translation ends when a stop codon (UAA, UAG, UGA) is reached. The initiation stage of translation brings together mRNA, tRNA bearing the first amino acid of the polypeptide, and two subunits of a ribosome. In the elongation stage, amino acids are added one by one to the preceding amino acid. The final step in translation is termination. When the ribosome reaches a STOP codon, there is no corresponding transfer RNA. Instead, a small protein called a “release factor” attaches to the stop codon. The release factor causes the whole complex to fall apart: messenger RNA, the two ribosome subunits, the new polypeptide. The messenger RNA can be translated many times, to produce many protein copies. mRNA binds to a ribosome, and the transfer RNA corresponding to the START codon binds to this complex. Ribosomes are composed of 2 subunits (large and small), which come together when the messenger RNA attaches during the initiation process. Elongation: the ribosome moves down the messenger RNA, adding new amino acids to the growing polypeptide chain. The ribosome has 2 sites for binding transfer RNA. The first RNA with its attached amino acid binds to the first site, and then the transfer RNA corresponding to the second codon bind to the second site. The ribosome then removes the amino acid from the first transfer RNA and attaches it to the second amino acid. At this point, the first transfer RNA is empty: no attached amino acid, and the second transfer RNA has a chain of 2 amino acids attached to it. The elongation cycle repeats as the ribosome moves down the messenger RNA, translating it one codon and one amino acid at a time. The process repeats until a STOP codon is reached. A number of ribosomes can translate a single mRNA molecule simultaneously forming a polyribosome.
Polyribosomes enable a cell to make many copies of a polypeptide very quickly. In a eukaryotic cell. The nuclear envelope separates transcription from translation. Extensive RNA processing occurs in the nucleus
Prokaryotic cells lack a nuclear envelope, allowing translation to begin while transcription progresses. The new polypeptide is now floating loose in the cytoplasm if translated by a free ribosome. Polypeptides fold spontaneously into their active configuration, and they spontaneously join with other polypeptides to form the final proteins. Often translation is not sufficient to make a functional protein, polypeptide chains are modified after translation. Sometimes other molecules are also attached to the polypeptides: sugars, lipids, phosphates, etc. All of these have special purposes for protein function. Completed proteins are targeted to specific sites in the cell. Two populations of ribosomes are evident in cells: free ribsomes (in the cytosol) and bound ribosomes (attached to the ER). Free ribosomes mostly synthesize proteins that function in the cytosol. Bound ribosomes make proteins of the endomembrane system and proteins that are secreted from the cell. Ribosomes are identical and can switch from free to bound. Polypeptide synthesis always begins in the cytosol. Synthesis finishes in the cytosol unless the polypeptide signals the ribosome to attach to the ER. Polypeptides destined for the ER or for secretion are marked by a signal peptide. A signal-recognition particle (SRP) binds to the signal peptide. The SRP brings the signal peptide and its ribosome to the ER. The natural replication of DNA produces occasional errors. DNA polymerase has an editing mechanism that decreases the rate, but it still exists. Typically genes incur base substitutions about once in every 10,000 to 1,000,000 cells. Since we have about 6 billion bases of DNA in each cell, virtually every cell in your body contains several mutations. Mutations can be harmful, lethal, helpful, silent. However, most mutations are neutral: have no effect. Only mutations in cells that become sperm or eggs—are passed on to future generations.
To be continued........
• Initiation
• Elongation
• Termination
The AUG start codon is recognized by methionyl-tRNA or Met. Once the start codon has been identified, the ribosome incorporates amino acids into a polypeptide chain. RNA is decoded by tRNA (transfer RNA) molecules, which each transport specific amino acids to the growing chain. Translation ends when a stop codon (UAA, UAG, UGA) is reached. The initiation stage of translation brings together mRNA, tRNA bearing the first amino acid of the polypeptide, and two subunits of a ribosome. In the elongation stage, amino acids are added one by one to the preceding amino acid. The final step in translation is termination. When the ribosome reaches a STOP codon, there is no corresponding transfer RNA. Instead, a small protein called a “release factor” attaches to the stop codon. The release factor causes the whole complex to fall apart: messenger RNA, the two ribosome subunits, the new polypeptide. The messenger RNA can be translated many times, to produce many protein copies. mRNA binds to a ribosome, and the transfer RNA corresponding to the START codon binds to this complex. Ribosomes are composed of 2 subunits (large and small), which come together when the messenger RNA attaches during the initiation process. Elongation: the ribosome moves down the messenger RNA, adding new amino acids to the growing polypeptide chain. The ribosome has 2 sites for binding transfer RNA. The first RNA with its attached amino acid binds to the first site, and then the transfer RNA corresponding to the second codon bind to the second site. The ribosome then removes the amino acid from the first transfer RNA and attaches it to the second amino acid. At this point, the first transfer RNA is empty: no attached amino acid, and the second transfer RNA has a chain of 2 amino acids attached to it. The elongation cycle repeats as the ribosome moves down the messenger RNA, translating it one codon and one amino acid at a time. The process repeats until a STOP codon is reached. A number of ribosomes can translate a single mRNA molecule simultaneously forming a polyribosome.
Polyribosomes enable a cell to make many copies of a polypeptide very quickly. In a eukaryotic cell. The nuclear envelope separates transcription from translation. Extensive RNA processing occurs in the nucleus
Prokaryotic cells lack a nuclear envelope, allowing translation to begin while transcription progresses. The new polypeptide is now floating loose in the cytoplasm if translated by a free ribosome. Polypeptides fold spontaneously into their active configuration, and they spontaneously join with other polypeptides to form the final proteins. Often translation is not sufficient to make a functional protein, polypeptide chains are modified after translation. Sometimes other molecules are also attached to the polypeptides: sugars, lipids, phosphates, etc. All of these have special purposes for protein function. Completed proteins are targeted to specific sites in the cell. Two populations of ribosomes are evident in cells: free ribsomes (in the cytosol) and bound ribosomes (attached to the ER). Free ribosomes mostly synthesize proteins that function in the cytosol. Bound ribosomes make proteins of the endomembrane system and proteins that are secreted from the cell. Ribosomes are identical and can switch from free to bound. Polypeptide synthesis always begins in the cytosol. Synthesis finishes in the cytosol unless the polypeptide signals the ribosome to attach to the ER. Polypeptides destined for the ER or for secretion are marked by a signal peptide. A signal-recognition particle (SRP) binds to the signal peptide. The SRP brings the signal peptide and its ribosome to the ER. The natural replication of DNA produces occasional errors. DNA polymerase has an editing mechanism that decreases the rate, but it still exists. Typically genes incur base substitutions about once in every 10,000 to 1,000,000 cells. Since we have about 6 billion bases of DNA in each cell, virtually every cell in your body contains several mutations. Mutations can be harmful, lethal, helpful, silent. However, most mutations are neutral: have no effect. Only mutations in cells that become sperm or eggs—are passed on to future generations.
To be continued........
How your cell makes very important proteins - part 2
The original transcript from the DNA is called pre-mRNA. It contains transcripts of both introns and exons. The introns are removed by a process called splicing to produce messenger RNA (mRNA). Ribozymes are catalytic RNA molecules that function as enzymes and can splice RNA. RNA splicing removes introns and joins exons. RNA Splicing can also be carried out by spliceosomes. How is it possible that there are millions of human antibodies when there are only about 30,000 genes? Alternative splicing refers to the different ways the exons of a gene may be combined, producing different forms of proteins within the same gene-coding region. Alternative pre-mRNA splicing is an important mechanism for regulating gene expression in higher eukaryotes. Proteins often have a modular architecture consisting of discrete structural and functional regions called domains. In many cases different exons code for the different domains in a protein. Translation is the RNA-directed synthesis of a polypeptide. Translation involves :mRNA. Ribosomes - Ribosomal RNA. Transfer RNA, Genetic coding – codons. Genetic information is encoded as a sequence of nonoverlapping base triplets, or codons. The gene determines the sequence of bases along the length of an mRNA molecule. Codons: 3 base code for the production of a specific amino acid, sequence of three of the four different nucleotides. Since there are 4 bases and 3 positions in each codon, there are 4 x 4 x 4 = 64 possible codons. 64 codons but only 20 amino acids, therefore most have more than 1 codon. 3 of the 64 codons are used as STOP signals; they are found at the end of every gene and mark the end of the protein. One codon is used as a START signal: it is at the start of every protein.
To be continued.........
To be continued.........
How your cell makes very important proteins- part 1
The information content of DNA is in the form of specific sequences of nucleotides along the DNA strands. The DNA inherited by an organism leads to specific traits by dictating the synthesis of proteins. The process by which DNA directs protein synthesis, gene expression includes two stages, called transcription and translation. Cells are governed by a cellular chain of command
– DNA --> RNA--> protein
Transcription:- Is the synthesis of RNA under the direction of DNA, Produces messenger RNA (mRNA)
Translation:- Is the actual synthesis of a polypeptide, which occurs under the direction of mRNA, Occurs on ribosomes. In prokaryotes transcription and translation occur together. In a eukaryotic cell the nuclear envelope separates transcription from translation. Extensive RNA processing occurs in the nucleus. Transcription is the DNA-directed synthesis of RNA. RNA synthesis, Is catalyzed by RNA polymerase, which pries the DNA strands apart and hooks together the RNA nucleotides, Follows the same base-pairing rules as DNA, except that in RNA, uracil substitutes for thymine. RNA is single stranded, not double stranded like DNA. RNA is short, only 1 gene long, where DNA is very long and contains many genes. RNA uses the sugar ribose instead of deoxyribose in DNA. RNA uses the base uracil (U) instead of thymine (T) in DNA. The stages of transcription are, Initiation, Elongation, Termination. Promoters signal the initiation of RNA synthesis. Transcription factors help eukaryotic RNA polymerase recognize promoter sequences. A crucial promoter DNA sequence is called a TATA box. RNA polymerase synthesizes a single strand of RNA against the DNA template strand (anti-sense strand), adding nucleotides to the 3’ end of the RNA chain. As RNA polymerase moves along the DNA it continues to untwist the double helix, exposing about 10 to 20 DNA bases at a time for pairing with RNA nucleotides. Specific sequences in the DNA signal termination of transcription. When one of these is encountered by the polymerase, the RNA transcript is released from the DNA and the double helix can zip up again. Most eukaryotic mRNAs aren’t ready to be translated into protein directly after being transcribed from DNA. mRNA requires processing. Transcription of RNA processing occur in the nucleus. After this, the messenger RNA moves to the cytoplasm for translation. The cell adds a protective cap to one end, and a tail of A’s to the other end. These both function to protect the RNA from enzymes that would degrade. Most of the genome consists of non-coding regions called introns. Non-coding regions may have specific chromosomal functions or have regulatory purposes, Introns also allow for alternative RNA splicing. Thus, an RNA copy of a gene is converted into messenger RNA by doing 2 things: Add protective bases to the ends, Cut out the introns, Each end of a pre-mRNA molecule is modified in a particular way, The 5¢ end receives a modified nucleotide cap, The 3¢ end gets a poly-A tail.
To be continued.......
– DNA --> RNA--> protein
Transcription:- Is the synthesis of RNA under the direction of DNA, Produces messenger RNA (mRNA)
Translation:- Is the actual synthesis of a polypeptide, which occurs under the direction of mRNA, Occurs on ribosomes. In prokaryotes transcription and translation occur together. In a eukaryotic cell the nuclear envelope separates transcription from translation. Extensive RNA processing occurs in the nucleus. Transcription is the DNA-directed synthesis of RNA. RNA synthesis, Is catalyzed by RNA polymerase, which pries the DNA strands apart and hooks together the RNA nucleotides, Follows the same base-pairing rules as DNA, except that in RNA, uracil substitutes for thymine. RNA is single stranded, not double stranded like DNA. RNA is short, only 1 gene long, where DNA is very long and contains many genes. RNA uses the sugar ribose instead of deoxyribose in DNA. RNA uses the base uracil (U) instead of thymine (T) in DNA. The stages of transcription are, Initiation, Elongation, Termination. Promoters signal the initiation of RNA synthesis. Transcription factors help eukaryotic RNA polymerase recognize promoter sequences. A crucial promoter DNA sequence is called a TATA box. RNA polymerase synthesizes a single strand of RNA against the DNA template strand (anti-sense strand), adding nucleotides to the 3’ end of the RNA chain. As RNA polymerase moves along the DNA it continues to untwist the double helix, exposing about 10 to 20 DNA bases at a time for pairing with RNA nucleotides. Specific sequences in the DNA signal termination of transcription. When one of these is encountered by the polymerase, the RNA transcript is released from the DNA and the double helix can zip up again. Most eukaryotic mRNAs aren’t ready to be translated into protein directly after being transcribed from DNA. mRNA requires processing. Transcription of RNA processing occur in the nucleus. After this, the messenger RNA moves to the cytoplasm for translation. The cell adds a protective cap to one end, and a tail of A’s to the other end. These both function to protect the RNA from enzymes that would degrade. Most of the genome consists of non-coding regions called introns. Non-coding regions may have specific chromosomal functions or have regulatory purposes, Introns also allow for alternative RNA splicing. Thus, an RNA copy of a gene is converted into messenger RNA by doing 2 things: Add protective bases to the ends, Cut out the introns, Each end of a pre-mRNA molecule is modified in a particular way, The 5¢ end receives a modified nucleotide cap, The 3¢ end gets a poly-A tail.
To be continued.......
Copying DNA
Today i hope to describe about Copying DNA. this is first post for Copying DNA..
• Polymerase Chain Reaction
• Also called PCR
• A method of making many copies of a piece of DNA
Steps in Copying DNA
• A DNA molecule is placed in a small test tube
• DNA polymerase that can work at high temps is added
• The DNA is heated to separate the two strands
• Primers, short pieces of DNA complementary to the ends of the molecule to be copied, are added
Copying DNA
• The tube is cooled, and DNA polymerase adds new bases to the separated strands
Human Genome Project
• Started in 1990
• Research effort to sequence all of our DNA (46 chromosomes)
• Over 3.3 billion nucleotides
• Mapping every gene location (loci)
• Conducted by scientists around the world
HGP Insights
• Only 2% of human genome codes for proteins (exons)
• Other 98% (introns) are non-coding
• Only about 20,000 to 25,000 genes (expected 100,000)
• Proteome – organism’s complete set of proteins
• About 8 million single nucleotide polymorphisms (SNP) – places where humans differ by a single nucleotide
• About ½ of genome comes from transposons (pieces of DNA that move to different locations on chromosomes)
Benefits of Human Genome Project
• Improvements in medical prevention of disease, gene therapies, diagnosis techniques …
• Production of useful protein products for use in medicine, agriculture, bioremediation and pharmaceutical industries.
• Improved bioinformatics – using computers to help in DNA sequencing
The Human Genome Project was started in 1989 with the goal of sequencing and identifying all three billion chemical units in the human genetic instruction set, finding the genetic roots of disease and then developing treatments. With the sequence in hand, the next step was to identify the genetic variants that increase the risk for common diseases like cancer and diabetes.
It was far too expensive at that time to think of sequencing patients’ whole genomes. So the National Institutes of Health embraced the idea for a "shortcut", which was to look just at sites on the genome where many people have a variant DNA unit. The theory behind the shortcut was that since the major diseases are common, so too would be the genetic variants that caused them. Natural selection keeps the human genome free of variants that damage health before children are grown, the theory held, but fails against variants that strike later in life, allowing them to become quite common. (In 2002 the National Institutes of Health started a $138 million project called the HapMap to catalog the common variants in European, East Asian and African genomes.)
The genome was broken into smaller pieces; approximately 150,000 base pairs in length. These pieces were then ligated into a type of vector known as "bacterial artificial chromosomes", or BACs, which are derived from bacterial chromosomes which have been genetically engineered. The vectors containing the genes can be inserted into bacteria where they are copied by the bacterial DNA replication machinery. Each of these pieces was then sequenced separately as a small "shotgun" project and then assembled. The larger, 150,000 base pairs go together to create chromosomes. This is known as the "hierarchical shotgun" approach, because the genome is first broken into relatively large chunks, which are then mapped to chromosomes before being selected for sequencing.
Funding came from the US government through the National Institutes of Health in the United States, and a UK charity organization, the Wellcome Trust, as well as numerous other groups from around the world. The funding supported a number of large sequencing centers including those at Whitehead Institute, the Sanger Centre, Washington University in St. Louis, and Baylor College of Medicine.
The Human Genome Project is considered a Mega Project because the human genome has approximately 3.3 billion base-pairs.
If the sequence obtained was to be stored in book form, and if each page contained 1000 base-pairs recorded and each book contained 1000 pages, then 3300 such books would be needed in order to store the complete genome. However, if expressed in units of computer data storage, 3.3 billion base-pairs recorded at 2 bits per pair would equal 786 megabytes of raw data. This is comparable to a fully data loaded CD.
• Research effort to sequence all of our DNA (46 chromosomes)
• Over 3.3 billion nucleotides
• Mapping every gene location (loci)
• Conducted by scientists around the world
HGP Insights
• Only 2% of human genome codes for proteins (exons)
• Other 98% (introns) are non-coding
• Only about 20,000 to 25,000 genes (expected 100,000)
• Proteome – organism’s complete set of proteins
• About 8 million single nucleotide polymorphisms (SNP) – places where humans differ by a single nucleotide
• About ½ of genome comes from transposons (pieces of DNA that move to different locations on chromosomes)
Benefits of Human Genome Project
• Improvements in medical prevention of disease, gene therapies, diagnosis techniques …
• Production of useful protein products for use in medicine, agriculture, bioremediation and pharmaceutical industries.
• Improved bioinformatics – using computers to help in DNA sequencing
The Human Genome Project was started in 1989 with the goal of sequencing and identifying all three billion chemical units in the human genetic instruction set, finding the genetic roots of disease and then developing treatments. With the sequence in hand, the next step was to identify the genetic variants that increase the risk for common diseases like cancer and diabetes.
It was far too expensive at that time to think of sequencing patients’ whole genomes. So the National Institutes of Health embraced the idea for a "shortcut", which was to look just at sites on the genome where many people have a variant DNA unit. The theory behind the shortcut was that since the major diseases are common, so too would be the genetic variants that caused them. Natural selection keeps the human genome free of variants that damage health before children are grown, the theory held, but fails against variants that strike later in life, allowing them to become quite common. (In 2002 the National Institutes of Health started a $138 million project called the HapMap to catalog the common variants in European, East Asian and African genomes.)
The genome was broken into smaller pieces; approximately 150,000 base pairs in length. These pieces were then ligated into a type of vector known as "bacterial artificial chromosomes", or BACs, which are derived from bacterial chromosomes which have been genetically engineered. The vectors containing the genes can be inserted into bacteria where they are copied by the bacterial DNA replication machinery. Each of these pieces was then sequenced separately as a small "shotgun" project and then assembled. The larger, 150,000 base pairs go together to create chromosomes. This is known as the "hierarchical shotgun" approach, because the genome is first broken into relatively large chunks, which are then mapped to chromosomes before being selected for sequencing.
Funding came from the US government through the National Institutes of Health in the United States, and a UK charity organization, the Wellcome Trust, as well as numerous other groups from around the world. The funding supported a number of large sequencing centers including those at Whitehead Institute, the Sanger Centre, Washington University in St. Louis, and Baylor College of Medicine.
The Human Genome Project is considered a Mega Project because the human genome has approximately 3.3 billion base-pairs.
If the sequence obtained was to be stored in book form, and if each page contained 1000 base-pairs recorded and each book contained 1000 pages, then 3300 such books would be needed in order to store the complete genome. However, if expressed in units of computer data storage, 3.3 billion base-pairs recorded at 2 bits per pair would equal 786 megabytes of raw data. This is comparable to a fully data loaded CD.
Genetic Engineering and Fish
What is a genetically engineered fish?
Genetically engineered (also called transgenic) fish are those that carry and transmit
one or more copies of a recombinant DNA sequence (i.e., a DNA sequence produced
in a laboratory using in vitro techniques). Because genetic engineering is defined by
the technology that is used to create and transfer the DNA sequence, and not the
source species of the donor DNA, even fish that are engineered with DNA derived
entirely from fish species are considered to be genetically engineered. Currently, no
genetically engineered fish has been approved for food production in the United
States. To date only one company, AquaBounty, has publicly announced that it has
requested FDA approval to market a genetically engineered food animal, a growth-
enhanced Atlantic salmon that is capable of growing 4 to 6 times faster (but not larg-
er) than standard salmon grown under the same conditions.
What are the science-based concerns associated with genetically engineered fish?
The greatest science-based concerns associated with genetically engineered fish are
those related to their inadvertent release or escape. Concerns range from interbreed-
ing with native fish populations to ecosystem effects resulting from heightened com-
petition for food and prey species. There is, in principle, no difference between the
types of concerns associated with the escape of genetically engineered fish and those
related to the escape of fish that differ from native populations in some other way,
such as captively bred populations (Lynch and O’Hely 2001). Ecological risk assess-
ment requires an evaluation of the fitness of the genetically engineered fish relative
to non–genetically engineered fish in the receiving population in order to determine
the probability that the transgene will spread into the native population. Ecological
impacts are the result of the characteristics of the organism, regardless of whether the
organism acquired those characteristics through natural selection, artificial selection,
or genetic engineering. The presence of genetically engineered fish does not a priori
have a negative effect on native populations. If genetically engineered fish are ill-suit-
ed to an environment or are physically unable to survive outside of containment, they
may pose little risk to the native ecosystems. Regulators apply a scientifically derived,
risk-based framework to assess the ecological risks involved with each transgene, spe-
cies, and receiving ecosystem combination on a case-by-case basis. Risks will be quite
specific to the gene, species, and site in question, and simple generalizations concerning
the risks (and benefits) of genetically engineered fish are not scientifically meaningful.
Commercialization of genetically engineered fish will likely depend on the development
of effective containment strategies. If genetically engineered fish are adequately con-
tained, they pose little risk to native populations. The NRC recommended the simulta-
neous use of multiple containment strategies for genetically engineered fish (National
Research Council 2004). Physical containment is an obvious first line of defense to pre-
vent the escape of genetically engineered fish. Examples of such measures may include
building facilities on land or in locations removed from native populations, or ensuring
that water chemistry (temperature, pH, salinity, and concentrations of certain chemi-
cals) is lethal to one or more life stages of the genetically engineered fish, such as treat-
ing effluent water to prevent the release of viable gametes or fry. Biological containment
or bioconfinement approaches such as sterilization are also being developed.
Genetically engineered (also called transgenic) fish are those that carry and transmit
one or more copies of a recombinant DNA sequence (i.e., a DNA sequence produced
in a laboratory using in vitro techniques). Because genetic engineering is defined by
the technology that is used to create and transfer the DNA sequence, and not the
source species of the donor DNA, even fish that are engineered with DNA derived
entirely from fish species are considered to be genetically engineered. Currently, no
genetically engineered fish has been approved for food production in the United
States. To date only one company, AquaBounty, has publicly announced that it has
requested FDA approval to market a genetically engineered food animal, a growth-
enhanced Atlantic salmon that is capable of growing 4 to 6 times faster (but not larg-
er) than standard salmon grown under the same conditions.
What are the science-based concerns associated with genetically engineered fish?
The greatest science-based concerns associated with genetically engineered fish are
those related to their inadvertent release or escape. Concerns range from interbreed-
ing with native fish populations to ecosystem effects resulting from heightened com-
petition for food and prey species. There is, in principle, no difference between the
types of concerns associated with the escape of genetically engineered fish and those
related to the escape of fish that differ from native populations in some other way,
such as captively bred populations (Lynch and O’Hely 2001). Ecological risk assess-
ment requires an evaluation of the fitness of the genetically engineered fish relative
to non–genetically engineered fish in the receiving population in order to determine
the probability that the transgene will spread into the native population. Ecological
impacts are the result of the characteristics of the organism, regardless of whether the
organism acquired those characteristics through natural selection, artificial selection,
or genetic engineering. The presence of genetically engineered fish does not a priori
have a negative effect on native populations. If genetically engineered fish are ill-suit-
ed to an environment or are physically unable to survive outside of containment, they
may pose little risk to the native ecosystems. Regulators apply a scientifically derived,
risk-based framework to assess the ecological risks involved with each transgene, spe-
cies, and receiving ecosystem combination on a case-by-case basis. Risks will be quite
specific to the gene, species, and site in question, and simple generalizations concerning
the risks (and benefits) of genetically engineered fish are not scientifically meaningful.
Commercialization of genetically engineered fish will likely depend on the development
of effective containment strategies. If genetically engineered fish are adequately con-
tained, they pose little risk to native populations. The NRC recommended the simulta-
neous use of multiple containment strategies for genetically engineered fish (National
Research Council 2004). Physical containment is an obvious first line of defense to pre-
vent the escape of genetically engineered fish. Examples of such measures may include
building facilities on land or in locations removed from native populations, or ensuring
that water chemistry (temperature, pH, salinity, and concentrations of certain chemi-
cals) is lethal to one or more life stages of the genetically engineered fish, such as treat-
ing effluent water to prevent the release of viable gametes or fry. Biological containment
or bioconfinement approaches such as sterilization are also being developed.
Cell Experiments & Activities
Cells are the smallest, most basic functional units that comprise living organisms. They are made up of smaller structures called organelles, which carry out different cell functions (for example, the mitochondria are responsible for respiration). Some ideas for cell science projects and activities include experimenting with salt and cell cytoplasm, examining cell nucleus and genome size, and extracting DNA from plant and animal cells.
SALT & CELL CYTOPLASM
All living cells have cytoplasm, which is a fluid-like substance (sometimes referred to as protoplasm) that cell bodies---such as mitochondria and ribosomes---float around in. In plant cells, the cytoplasm is contained both by an inner cell membrane, and an outer cell wall. As an experiment, you can observe the effect salt has on plant cell cytoplasm, assuming---of course---that it can penetrate the cell wall and membrane. According to crystal-clear-science-projects.com, you will need to take a small tissue sample from an onion and examine it under a compound microscope (100x magnification will be sufficient). You can then saturate your sample with a five percent solution of salt in water, observe, and do the same with a 10 percent solution. You may discover that the salt dissolves the cytoplasm of the cells in your onion, allowing you to have a better glimpse at the inner-workings of the plant cell.
CELL NUCLEUS & GENOME SIZE
Every species of animal stores DNA in the nuclei of its cells. However, some store more DNA than others, which correlates to a larger genome size. According to sciencebuddies.org, genome size is determined by weighing DNA, and is measured in picograms (one picogram equals one trillionth of a gram). For this experiment, you will determine if there is a correlation between the size of animal genomes and the size of their cell nuclei. To do this, you will need to utilize the Cell Size Database, which lists the genome sizes and nuclei sizes (measured in μm2, or in millionths of a square meter) of different animals. You will likely want to organize your results according to animal kingdom (for example, have a section for amphibians, mammals, etc.) and make a chart and/or graph to display them.
EXTRACTING DNA FROM PLANT & ANIMAL CELLS
This experiment will require equipment and chemicals that you may only be able to access at a high school or---perhaps more likely---university or college laboratory. According to usc.edu, your goal will be to determine if it is easier to extract DNA from an animal cell as opposed to a plant cell (which, as mentioned earlier, features a sturdy cell wall). You will need to take samples of animals and plants, such as small bits of chicken liver or onion, and prep them for extraction. This requires adding a buffering solution, a detergent and a neutralizing solution to each sample, and then subjecting each to a centrifuge (which rotates fluids at extremely high speeds). Finally, you need to add isopropanol to isolate and extract the DNA. For an additional twist on the experiment, treat plant samples with cellulase---which will breakdown cell walls---and see what effect this has on extraction.
SALT & CELL CYTOPLASM
All living cells have cytoplasm, which is a fluid-like substance (sometimes referred to as protoplasm) that cell bodies---such as mitochondria and ribosomes---float around in. In plant cells, the cytoplasm is contained both by an inner cell membrane, and an outer cell wall. As an experiment, you can observe the effect salt has on plant cell cytoplasm, assuming---of course---that it can penetrate the cell wall and membrane. According to crystal-clear-science-projects.com, you will need to take a small tissue sample from an onion and examine it under a compound microscope (100x magnification will be sufficient). You can then saturate your sample with a five percent solution of salt in water, observe, and do the same with a 10 percent solution. You may discover that the salt dissolves the cytoplasm of the cells in your onion, allowing you to have a better glimpse at the inner-workings of the plant cell.
CELL NUCLEUS & GENOME SIZE
Every species of animal stores DNA in the nuclei of its cells. However, some store more DNA than others, which correlates to a larger genome size. According to sciencebuddies.org, genome size is determined by weighing DNA, and is measured in picograms (one picogram equals one trillionth of a gram). For this experiment, you will determine if there is a correlation between the size of animal genomes and the size of their cell nuclei. To do this, you will need to utilize the Cell Size Database, which lists the genome sizes and nuclei sizes (measured in μm2, or in millionths of a square meter) of different animals. You will likely want to organize your results according to animal kingdom (for example, have a section for amphibians, mammals, etc.) and make a chart and/or graph to display them.
EXTRACTING DNA FROM PLANT & ANIMAL CELLS
This experiment will require equipment and chemicals that you may only be able to access at a high school or---perhaps more likely---university or college laboratory. According to usc.edu, your goal will be to determine if it is easier to extract DNA from an animal cell as opposed to a plant cell (which, as mentioned earlier, features a sturdy cell wall). You will need to take samples of animals and plants, such as small bits of chicken liver or onion, and prep them for extraction. This requires adding a buffering solution, a detergent and a neutralizing solution to each sample, and then subjecting each to a centrifuge (which rotates fluids at extremely high speeds). Finally, you need to add isopropanol to isolate and extract the DNA. For an additional twist on the experiment, treat plant samples with cellulase---which will breakdown cell walls---and see what effect this has on extraction.
The Difference of the Genomic DNA Extraction Between Animal & Plant
The structure of double-stranded DNA is universal in all living cells, but differences occur in the methods for extracting genomic DNA from animal and plant cells. Genomic DNA is found in the nucleus of cells. The amount and purity of extracted DNA depends on the type and size of the cell, as certain cells contain more DNA and impurities than others.
GENERAL DNA EXTRACTION
Plant and animal cells treated with a soapy substance will degrade the lipids in the cell and nuclear membranes. The DNA mixture will then separate from the cell membranes and proteins. The DNA in solution can be precipitated using alcohol. Depending on the amount in the sample, DNA may be visible by the naked eye. Such a simple procedure does not necessarily produce DNA of high purity.
PLANT AND ANIMAL CELLS
Plant cells are distinguishable from animal cells by their rigid cell wall and organelles like the chloroplast. They also contain proteins and enzymes that play a role in photosynthesis. Some plant cells are polyploidy, meaning they have more than one copy of each chromosome per cell. Cellular processes occurring in plants such as photosynthesis produce a range of secondary metabolites. Animal cells do not have a cell wall, but still need to be treated with chemicals like sodium dodecyl sulphate (SDS) to disrupt the cell membrane to release genomic DNA.
PLANT DNA EXTRACTION
Plant genomic DNA is more difficult to extract because of the plant's cell wall, which is removed by homogenization, or by adding cellulase to degrade the cellulose that makes up the cell wall. Also, the metabolites present in the plant cell may interfere with genomic DNA extraction by contaminating the DNA sample during the precipitation process.
ANIMAL DNA EXTRACTION
Peripheral blood leukocytes are a main source of animal genomic DNA, but sample collection is difficult as blood must be withdrawn from the animal. Blood contains a range of compounds like proteins, lipids, white blood cells, red blood cells, platelets, and plasma, which can contaminate the DNA sample. The primary contaminant of animal DNA extracted from blood samples is heme, the non-protein component of hemoglobin.
DIFFERENCES
The differences between plant and animal DNA lie in the sequence of bases in the helix. Compounds found in plant cells are absent in animal cells, and DNA base sequences reflect this, as the genomic plant DNA is often larger than animal DNA. These differences affect extraction methods, as it impacts on yield and purity of DNA.
GENERAL DNA EXTRACTION
Plant and animal cells treated with a soapy substance will degrade the lipids in the cell and nuclear membranes. The DNA mixture will then separate from the cell membranes and proteins. The DNA in solution can be precipitated using alcohol. Depending on the amount in the sample, DNA may be visible by the naked eye. Such a simple procedure does not necessarily produce DNA of high purity.
PLANT AND ANIMAL CELLS
Plant cells are distinguishable from animal cells by their rigid cell wall and organelles like the chloroplast. They also contain proteins and enzymes that play a role in photosynthesis. Some plant cells are polyploidy, meaning they have more than one copy of each chromosome per cell. Cellular processes occurring in plants such as photosynthesis produce a range of secondary metabolites. Animal cells do not have a cell wall, but still need to be treated with chemicals like sodium dodecyl sulphate (SDS) to disrupt the cell membrane to release genomic DNA.
PLANT DNA EXTRACTION
Plant genomic DNA is more difficult to extract because of the plant's cell wall, which is removed by homogenization, or by adding cellulase to degrade the cellulose that makes up the cell wall. Also, the metabolites present in the plant cell may interfere with genomic DNA extraction by contaminating the DNA sample during the precipitation process.
ANIMAL DNA EXTRACTION
Peripheral blood leukocytes are a main source of animal genomic DNA, but sample collection is difficult as blood must be withdrawn from the animal. Blood contains a range of compounds like proteins, lipids, white blood cells, red blood cells, platelets, and plasma, which can contaminate the DNA sample. The primary contaminant of animal DNA extracted from blood samples is heme, the non-protein component of hemoglobin.
DIFFERENCES
The differences between plant and animal DNA lie in the sequence of bases in the helix. Compounds found in plant cells are absent in animal cells, and DNA base sequences reflect this, as the genomic plant DNA is often larger than animal DNA. These differences affect extraction methods, as it impacts on yield and purity of DNA.
Cloning and relation to plasmids
The use of cloning is interrelated with recombinant DNA in classical biology, as the term "clone" refers to a cell or organism derived from a parental organism, with modern biology referring to the term as a collection of cells derived from the same cell that remain identical. In the classical instance, the use of recombinant DNA provides the initial cell from which the host organism is then expected to recapitulate when it undergoes further cell division, with bacteria remaining a prime example due to the use of viral vectors in medicine that contain recombinant DNA inserted into a structure known as a plasmid. Plasmids are extrachromosomal self-replicating circular forms of DNA present in most bacteria, such as Escherichia coli (E. Coli), containing genes related to catabolism and metabolic activity, and allowing the carrier bacterium to survive and reproduce in conditions present within other species and environments. These genes represent characteristics of resistance to bacteriophages and antibiotics and some heavy metals, but can also be fairly easily removed or separated from the plasmid by restriction endonucleases, which regularly produce "sticky ends" and allow the attachment of a selected segment of DNA, which codes for more "reparative" substances, such as peptide hormone medications including insulin, growth hormone, and oxytocin. In the introduction of useful genes into the plasmid, the bacteria are then used as a viral vector, which are encouraged to reproduce so as to recapitulate the altered DNA within other cells it infects, and increase the amount of cells with the recombinant DNA present within them.The use of plasmids is also key within gene therapy, where their related viruses are used as cloning vectors or carriers, which are means of transporting and passing on genes in recombinant DNA through viral reproduction throughout an organism. Plasmids contain three common features—a replicator, selectable marker and a cloning site. The replicator or "ori" refers to the origin of replication with regard to location and bacteria where replication begins. The marker refers to a particular gene that usually contains resistance to an antibiotic, but may also refer to a gene that is attached alongside the desired one, such as that which confers luminescence to allow identification of successfully recombined DNA. The cloning site is a sequence of nucleotides representing one or more positions where cleavage by restriction endonucleases occurs.[1] Most eukaryotes do not maintain canonical plasmids; yeast is a notable exception. In addition, the Ti plasmid of the bacterium Agrobacterium tumefaciens can be used to integrate foreign DNA into the genomes of many plants. Other methods of introducing or creating recombinant DNA in eukaryotes include homologous recombination and transfection with modified viruses.
DNA (DEOXYRIBOSE NUCLEIC ACID)
DNA strand is made from alternating phospate and sugar residues. Thesre two strands run in opposite directions to each other and therfore antiparallel Attached to each sugar is one of four types of molecules called bases. The sugar in DNA is 2 - deoxyribose which is apentose sugar searches of DNA into the related nuclear acid RNA in aproesss sugsrs are joinrd to phospate groups that from phosphodiester bonds btwn the third and4th carbon atoms adjacent sugar rings.
DNA is a long polymer made from repeating units called nucleotides. The DNA is chain is 20 - 26 angstroms wide. DNA polymers can be very large moleculars containing millions of nucleotides chemically with backbones made of sugars and phospates groups joined by ester bonds these onformation is using the genetic code. Phospate groups are joined by ester bonds. In living organisms.
DNA does not usually exist as a single molecule but it exists as a pair of molecules that are held tightly together. These two long strands and entwine like vines in the shape a double helix. which holds chain together and a base which interacts with the other DNA strand in the helix. A base linked to a sugar is nucleiotide. If muultiple nucleiotide are linked to together as in DNA this polymer is known as a polynucleiotide
DNA is a long polymer made from repeating units called nucleotides. The DNA is chain is 20 - 26 angstroms wide. DNA polymers can be very large moleculars containing millions of nucleotides chemically with backbones made of sugars and phospates groups joined by ester bonds these onformation is using the genetic code. Phospate groups are joined by ester bonds. In living organisms.
DNA does not usually exist as a single molecule but it exists as a pair of molecules that are held tightly together. These two long strands and entwine like vines in the shape a double helix. which holds chain together and a base which interacts with the other DNA strand in the helix. A base linked to a sugar is nucleiotide. If muultiple nucleiotide are linked to together as in DNA this polymer is known as a polynucleiotide
History of DNA Reseach
DNA was first isolated by the Swiss physician Friedrich Miescher who, in 1869, discovered a microscopic substance in the pus of discarded surgical bandages. As it resided in the nuclei of cells, he called it "nuclein". In 1919, Phoebus Levene identified the base, sugar and phosphate nucleotide unit. Levene suggested that DNA consisted of a string of nucleotide units linked together through the phosphate groups. However, Levene thought the chain was short and the bases repeated in a fixed order. In 1937 William Astbury produced the first X-ray diffraction patterns that showed that DNA had a regular structure.
In 1928, Frederick Griffith discovered that traits of the "smooth" form of the Pneumococcus could be transferred to the "rough" form of the same bacteria by mixing killed "smooth" bacteria with the live "rough" form. This system provided the first clear suggestion that DNA carried genetic information—the Avery-MacLeod-McCarty experiment—when Oswald Avery, along with coworkers Colin MacLeod and Maclyn McCarty, identified DNA as the transforming principle in 1943. DNA's role in heredity was confirmed in 1952, when Alfred Hershey and Martha Chase in the Hershey-Chase experiment showed that DNA is the genetic material of the T2 phage.
In 1928, Frederick Griffith discovered that traits of the "smooth" form of the Pneumococcus could be transferred to the "rough" form of the same bacteria by mixing killed "smooth" bacteria with the live "rough" form. This system provided the first clear suggestion that DNA carried genetic information—the Avery-MacLeod-McCarty experiment—when Oswald Avery, along with coworkers Colin MacLeod and Maclyn McCarty, identified DNA as the transforming principle in 1943. DNA's role in heredity was confirmed in 1952, when Alfred Hershey and Martha Chase in the Hershey-Chase experiment showed that DNA is the genetic material of the T2 phage.
In 1953 James D. Watson and Francis Crick suggested what is now accepted as the first correct double-helix model of DNA structure in the journal Nature. Their double-helix, molecular model of DNA was then based on a single X-ray diffraction image taken by Rosalind Franklin and Raymond Gosling in May 1952, as well as the information that the DNA bases were paired—also obtained through private communications from Erwin Chargaff in the previous years. Chargaff's rules played a very important role in establishing double-helix configurations for B-DNA as well as A-DNA.
Experimental evidence supporting the Watson and Crick model were published in a series of five articles in the same issue of Nature. Of these, Franklin and Gosling's paper was the first publication of their own X-ray diffraction data and original analysis method that partially supported the Watson and Crick mode; this issue also contained an article on DNA structure by Maurice Wilkins and two of his colleagues, whose analysis and in vivo B-DNA X-ray patterns also supported the presence in vivo of the double-helical DNA configurations as proposed by Crick and Watson for their double-helix molecular model of DNA in the previous two pages of Nature. In 1962, after Franklin's death, Watson, Crick, and Wilkins jointly received the Nobel Prize in Physiology or Medicine. Unfortunately, Nobel rules of the time allowed only living recipients, but a vigorous debate continues on who should receive credit for the discovery.
In an influential presentation in 1957, Crick laid out the "Central Dogma" of molecular biology, which foretold the relationship between DNA, RNA, and proteins, and articulated the "adaptor hypothesis". Final confirmation of the replication mechanism that was implied by the double-helical structure followed in 1958 through the Meselson-Stahl experiment. Further work by Crick and coworkers showed that the genetic code was based on non-overlapping triplets of bases, called codons, allowing Har Gobind Khorana, Robert W. Holley and Marshall Warren Nirenberg to decipher the genetic code. These findings represent the birth of molecular biology
Grooves
Twin helical strands form the DNA backbone. Another double helix may be found by tracing the spaces, or grooves, between the strands. These voids are adjacent to the base pairs and may provide a binding site. As the strands are not directly opposite each other, the grooves are unequally sized. One groove, the major groove, is 22 Å wide and the other, the minor groove, is 12 Å wide. The narrowness of the minor groove means that the edges of the bases are more accessible in the major groove. As a result, proteins like transcription factors that can bind to specific sequences in double-stranded DNA usually make contacts to the sides of the bases exposed in the major groove. This situation varies in unusual conformations of DNA within the cell (see below), but the major and minor grooves are always named to reflect the differences in size that would be seen if the DNA is twisted back into the ordinary B form
DEOXYRIBOSE NUCLEIC ACID
DNA strand is made from alternating phospate and sugar residues. Thesre two strands run in opposite directions to each other and therfore antiparallel Attached to each sugar is one of four types of molecules called bases. The sugar in DNA is 2-deoxyribose which is apentose sugar searches of DNA into the related nuclear acid RNA in aproesss sugsrs are joinrd to phospate groups that from phosphodiester bonds btwn the third and4th carbon atoms adjacent sugar rings.
DNA is a long polymer made from repeating units called nucleotides. The DNA is chain is 20-26 angstroms wide. DNA polymers can be very large moleculars containing millions of nucleotides chemically with backbones made of sugars and phospates groups joined by ester bonds these onformation is using the genetic code. Phospate groups are joined by ester bonds. In living organisms,
DNA does not usually exist as a single molecule but it exists as a pair of molecules that are held tightly together. These two long strands and entwine like vines, in the shape a double helix. which holds chain together and a base which interacts with the other DNA strand in the helix. A base linked to a sugar is nucleiotide. If muultiple nucleiotide are linked to together, as in DNA this polymer is known as a polynucleiotide.
DNA is a long polymer made from repeating units called nucleotides. The DNA is chain is 20-26 angstroms wide. DNA polymers can be very large moleculars containing millions of nucleotides chemically with backbones made of sugars and phospates groups joined by ester bonds these onformation is using the genetic code. Phospate groups are joined by ester bonds. In living organisms,
DNA does not usually exist as a single molecule but it exists as a pair of molecules that are held tightly together. These two long strands and entwine like vines, in the shape a double helix. which holds chain together and a base which interacts with the other DNA strand in the helix. A base linked to a sugar is nucleiotide. If muultiple nucleiotide are linked to together, as in DNA this polymer is known as a polynucleiotide.
GENETIC DISORDER
Genetic disorder is a condition caused by abnormalities in genes or chromosomes. While some diseases such as cancer. Cancer are due to genetic abnormalities acquired in a few cells during life. The term "genetic disease" most commonly refers to diseases present in all cells of the body and present since conception. Some genetic disorders are caused by chromosomal abnormalities due to errors in meiosis, the process which produces reproductive cells such as sperm and eggs. Examples include Down syndrome, Turner Syndrome and Klinefelter's syndrome. Other genetic changes may occur during the production of germ cells by the parent. One example is the triplet expansion repeat mutations which can cause fragile X syndrome or Huntington's disease. Defective genes may also be inherited intact from the parents. In this case, the genetic disorder is known as a hereditary disease. This can often happen unexpectedly when two healthy carriers of a defective recessive gene reproduce, but can also happen when the defective gene is dominant.
About 4,000 genetic disorders are known with more being discovered. Most disorders are quite rare and affect one person in every several thousands or millions. Cystic fibrosis is one of the most common genetic disorders around 5% of the population of the United States carry at least one copy of the defective gene. Some types of recessive gene disorder confer an advantage in the heterozygous state in certain environments.Genetic diseases are typically diagnosed and treated by geneticists. Genetic counselors assist the physicians and directly counsel patients. The study of genetic diseases is a scientific discipline whose theoretical underpinning is based on population genetics.
About 4,000 genetic disorders are known with more being discovered. Most disorders are quite rare and affect one person in every several thousands or millions. Cystic fibrosis is one of the most common genetic disorders around 5% of the population of the United States carry at least one copy of the defective gene. Some types of recessive gene disorder confer an advantage in the heterozygous state in certain environments.Genetic diseases are typically diagnosed and treated by geneticists. Genetic counselors assist the physicians and directly counsel patients. The study of genetic diseases is a scientific discipline whose theoretical underpinning is based on population genetics.
MONOCLONAL ANTIBODIES
Monoclonal antibodies are monospecific antibodies that are the same because they are made by identical immune cells that are all clones of a unique parent cells.
Given almost any substance. It is possible to create monoclonal antibodies that specifically bind to that substance; they can then serve to detect or purify that substance. This has become an important tool in biochemistry, molecular biology and medicine. When used as medications, the non-proprietary drug name ends in -mab.
Given almost any substance. It is possible to create monoclonal antibodies that specifically bind to that substance; they can then serve to detect or purify that substance. This has become an important tool in biochemistry, molecular biology and medicine. When used as medications, the non-proprietary drug name ends in -mab.
Phylogetics DNA
Every living cells contains DNA, RNA and protiens. closely related organisms generally have degree of agreement in the molecular structure of these substances,Heterogenous nuclear ribonucleoprotiens are spliceosomal macromolecular assemblages and thus actively participate in pre-mRNA metabloism.
conserved sequnces. such as mitochondrial DNA are expected to accumalate mutations over time and assuming a constant rate of mutation provide molecular interaction features.
Molecular characterization of human hnRNP A3 showed that while the recombinant hnRNP A3 with its 296 amino acids migrates as excpted as 32 kDA protien on SDS-PAGE analysis, it is recoginzed by the patient's sera as a 50 kda highly related ye unknownv crossreactive protien.
The sequence comparision. however may be insufficient for deduction of its functional role patients diagnozed with the suspected disease. therefore we followed the suggestion of ponting CS and Russel RRSurprisingly, neither the 50 kda nor the 32kda protien was dected in the suspected disease.
conserved sequnces. such as mitochondrial DNA are expected to accumalate mutations over time and assuming a constant rate of mutation provide molecular interaction features.
Molecular characterization of human hnRNP A3 showed that while the recombinant hnRNP A3 with its 296 amino acids migrates as excpted as 32 kDA protien on SDS-PAGE analysis, it is recoginzed by the patient's sera as a 50 kda highly related ye unknownv crossreactive protien.
The sequence comparision. however may be insufficient for deduction of its functional role patients diagnozed with the suspected disease. therefore we followed the suggestion of ponting CS and Russel RRSurprisingly, neither the 50 kda nor the 32kda protien was dected in the suspected disease.
RECOMBINANT DNA
Recombinant DNA is a form of artificial DNA that is engineered through the combination of insertion of one or more DNA strands. Therefor combining DNA sequences that would not normally occur together. In terms of genetic modification, recombinant DNA is produced through the addition of relevant DNA into an existing organismal genome, such as the plasmid of bacteria, to code for or alter different traits for a specific purpose, such as immunity. It differs from genetic recombination, in that it does not occur through processes within the cell or ribosome, but is exclusively engineered.The Recombinant DNA technique was engineered by Stanley Norman Cohen and Herbert Boyer in 1973. They published their findings in a 1974 paper entitled "Construction of Biologically Functional Bacterial Plasmids in vitro". Which described a technique to isolate and amplify genes or DNA segments and insert them into another cell with precision, creating a transgenic bacterium.
DNA (Deoxyribonucleic Acid)
Deoxyribonucleic Acid (DNA) is genetic material found in the cells of all living organisms. DNA is the fundamental building blocks for life. Nearly every cell (with a nucleus) in a person's body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but DNA can also found in the mitochondria (where it is called mitochondrial DNA or mtDNA).The information in DNA is made up four bases which combine to form chains. These bases include two purines (Adenine and Guanine) and two pyrimidines (Cytosine and Thymine). These are commonly referred to as A, G, C and T respectively. Human DNA consists of about 3 billion bases, and more than 99 percent of those bases are the same in all people. It is the order, or sequence, of these bases which determines genetic characteristics.
The structure of the double helix is somewhat like a ladder, with the base pairs forming the ladder's rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder. Each base is attached to a Sugar (S) molecule and Phosphate (P) molecule. Together, a base, sugar, and phosphate are called a nucleotide. Nucleotides are arranged in two long strands that form a spiral called a double helix. The number of purine bases in DNA is equal to the number of pyrimidines. This is due to the law of complimentary base pairing. which is Thymine (T) can only pair with Adenine (A), and Guanine (G) can only pair with Cytosine (C). Knowing this rule, we could predict the base sequence of one DNA strand if we knew the sequence of bases in the complimentary strand.
The structure of the double helix is somewhat like a ladder, with the base pairs forming the ladder's rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder. Each base is attached to a Sugar (S) molecule and Phosphate (P) molecule. Together, a base, sugar, and phosphate are called a nucleotide. Nucleotides are arranged in two long strands that form a spiral called a double helix. The number of purine bases in DNA is equal to the number of pyrimidines. This is due to the law of complimentary base pairing. which is Thymine (T) can only pair with Adenine (A), and Guanine (G) can only pair with Cytosine (C). Knowing this rule, we could predict the base sequence of one DNA strand if we knew the sequence of bases in the complimentary strand.
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