Related Research Articles
The genetic code is the set of rules used by living cells to translate information encoded within genetic material into proteins. Translation is accomplished by the ribosome, which links proteinogenic amino acids in an order specified by messenger RNA (mRNA), using transfer RNA (tRNA) molecules to carry amino acids and to read the mRNA three nucleotides at a time. The genetic code is highly similar among all organisms and can be expressed in a simple table with 64 entries.
Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid (DNA) are nucleic acids. Along with lipids, proteins, and carbohydrates, nucleic acids constitute one of the four major macromolecules essential for all known forms of life. Like DNA, RNA is assembled as a chain of nucleotides, but unlike DNA, RNA is found in nature as a single strand folded onto itself, rather than a paired double strand. Cellular organisms use messenger RNA (mRNA) to convey genetic information that directs synthesis of specific proteins. Many viruses encode their genetic information using an RNA genome.
In molecular biology, a stop codon is a codon that signals the termination of the translation process of the current protein. Most codons in messenger RNA correspond to the addition of an amino acid to a growing polypeptide chain, which may ultimately become a protein; stop codons signal the termination of this process by binding release factors, which cause the ribosomal subunits to disassociate, releasing the amino acid chain.
The human genome is a complete set of nucleic acid sequences for humans, encoded as DNA within the 23 chromosome pairs in cell nuclei and in a small DNA molecule found within individual mitochondria. These are usually treated separately as the nuclear genome and the mitochondrial genome. Human genomes include both protein-coding DNA genes and noncoding DNA. Haploid human genomes, which are contained in germ cells consist of three billion DNA base pairs, while diploid genomes have twice the DNA content. While there are significant differences among the genomes of human individuals, these are considerably smaller than the differences between humans and their closest living relatives, the bonobos and chimpanzees.
Mitochondrial DNA is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, adenosine triphosphate (ATP). Mitochondrial DNA is only a small portion of the DNA in a eukaryotic cell; most of the DNA can be found in the cell nucleus and, in plants and algae, also in plastids such as chloroplasts.
Codon usage bias refers to differences in the frequency of occurrence of synonymous codons in coding DNA. A codon is a series of three nucleotides that encodes a specific amino acid residue in a polypeptide chain or for the termination of translation.
In bioinformatics, sequence analysis is the process of subjecting a DNA, RNA or peptide sequence to any of a wide range of analytical methods to understand its features, function, structure, or evolution. Methodologies used include sequence alignment, searches against biological databases, and others. Since the development of methods of high-throughput production of gene and protein sequences, the rate of addition of new sequences to the databases increased exponentially. Such a collection of sequences does not, by itself, increase the scientist's understanding of the biology of organisms. However, comparing these new sequences to those with known functions is a key way of understanding the biology of an organism from which the new sequence comes. Thus, sequence analysis can be used to assign function to genes and proteins by the study of the similarities between the compared sequences. Nowadays, there are many tools and techniques that provide the sequence comparisons and analyze the alignment product to understand its biology.
In molecular biology and genetics, translation is the process in which ribosomes in the cytoplasm or endoplasmic reticulum synthesize proteins after the process of transcription of DNA to RNA in the cell's nucleus. The entire process is called gene expression.
In molecular biology, a reading frame is a way of dividing the sequence of nucleotides in a nucleic acid molecule into a set of consecutive, non-overlapping triplets. Where these triplets equate to amino acids or stop signals during translation, they are called codons.
Chargaff's rules state that DNA from any species of any organism should have a 1:1 stoichiometric ratio of purine and pyrimidine bases and, more specifically, that the amount of guanine should be equal to cytosine and the amount of adenine should be equal to thymine. This pattern is found in both strands of the DNA. They were discovered by Austrian-born chemist Erwin Chargaff, in the late 1940s.
A point mutation or substitution is a genetic mutation where a single nucleotide base is changed, inserted or deleted from a DNA or RNA sequence of an organism's genome. Point mutations have a variety of effects on the downstream protein product—consequences that are moderately predictable based upon the specifics of the mutation. These consequences can range from no effect to deleterious effects, with regard to protein production, composition, and function.
In biology, a gene is a basic unit of heredity and a sequence of nucleotides in DNA or RNA that encodes the synthesis of a gene product, either RNA or protein.
MT-ND6 is a gene of the mitochondrial genome coding for the NADH-ubiquinone oxidoreductase chain 6 protein (ND6). The ND6 protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain. Variations in the human MT-ND6 gene are associated with Leigh's syndrome, Leber's hereditary optic neuropathy (LHON) and dystonia.
ADGRV1, also known as G protein-coupled receptor 98 (GPR98) or Very Large G-protein coupled receptor 1 (VLGR1), is a protein that in humans is encoded by the GPR98 gene. Several alternatively spliced transcripts have been described.
Lipoamide acyltransferase component of branched-chain alpha-keto acid dehydrogenase complex, mitochondrial is an enzyme that in humans is encoded by the DBT gene.
ADP/ATP translocase 3, also known as solute carrier family 25 member 6, is a protein that in humans is encoded by the SLC25A6 gene.
The vertebrate mitochondrial code is the genetic code found in the mitochondria of all vertebrata.
The invertebrate mitochondrial code is a genetic code used by the mitochondrial genome of invertebrates.
The alternative flatworm mitochondrial code is a genetic code found in the mitochondria of Platyhelminthes and Nematodes.
References
This article incorporates text from the United States National Library of Medicine, which is in the public domain. [1]
- 1 2 Elzanowski A, Ostell J, Leipe D, Soussov V. "The Genetic Codes". Taxonomy browser. National Center for Biotechnology Information (NCBI), U.S. National Library of Medicine. Retrieved 18 March 2016.
- ↑ H. Himeno; H. Masaki; T. Kawai; T. Ohta; I. Kumagai; K. Miura; K. Watanabe (1987). "Unusual genetic codes and a novel gene structure for tRNA(AGYSer) in starfish mitochondrial DNA". Gene. 56 (2–3): 219–30. doi:10.1016/0378-1119(87)90139-9. PMID 3678836.
- ↑ H. T. Jacobs; D. J. Elliott; V. B. Math; A. Farquharson (20 July 1988). "Nucleotide sequence and gene organization of sea urchin mitochondrial DNA". J Mol Biol. 202 (2): 185–217. doi:10.1016/0022-2836(88)90452-4. PMID 3172215.
- ↑ P. Cantatore; M. Roberti; G. Rainaldi; M. N. Gadaleta; C. Saccone (5 July 1989). "The complete nucleotide sequence, gene organization, and genetic code of the mitochondrial genome of Paracentrotus lividus". J Biol Chem. 264 (19): 10965–75. doi: 10.1016/S0021-9258(18)60413-2 . PMID 2544576.
- ↑ M. J. Telford; E. A. Herniou; R. B. Russell; D. T. Littlewood (10 October 2000). "Changes in mitochondrial genetic codes as phylogenetic characters: two examples from the flatworms". Proc Natl Acad Sci U S A. 97 (21): 11359–64. Bibcode:2000PNAS...9711359T. doi: 10.1073/pnas.97.21.11359 . PMC 17205 . PMID 11027335.
