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Alu Elements
An Alu element is a short stretch of DNA originally characterized by the action of the ''Arthrobacter luteus (Alu)'' restriction endonuclease. ''Alu'' elements are the most abundant transposable elements, containing over one million copies dispersed throughout the human genome. ''Alu'' elements were thought to be selfish or parasitic DNA, because their sole known function is self reproduction. However, they are likely to play a role in evolution and have been used as genetic markers. They are derived from the small cytoplasmic 7SL RNA, a component of the signal recognition particle. ''Alu'' elements are highly conserved within primate genomes and originated in the genome of an ancestor of Supraprimates. ''Alu'' insertions have been implicated in several inherited human diseases and in various forms of cancer. The study of Alu elements has also been important in elucidating human population genetics and the evolution of primates, including the evolution of humans. Alu fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthrobacter Luteus
''Arthrobacter luteus'' (ALU) is a species of gram-positive bacteria in the genus '' Arthrobacter''. ''A. luteus'' is facultatively anaerobic, pleomorphic, branching, non-motile, non-sporulating, non-acid-fast, catalase-positive, and rod-shaped (0.6–1.0 μm × 0.8–10.0 μm). A restriction endonuclease enzyme is extracted from the bacterium and acts at the centre of a palindromic tetranucleotide sequence to give even-ended duplex DNA fragments phosphorylated at the 5'-end. The restriction site ''Alu-I'' itself is a 4-base cutter: AG/CT. The Alu retrotransposon is named after the bacterium's abbreviation. The bacterium is also used to produce zymolyase, which can degrade yeast cell wall. Background ''Arthrobacter luteus'' was isolated from brewery sewage in research done in Takasaki, Japan in 1969. The team studied the bacteria isolated taxonomically and found them to be gram-positive, facultatively anaerobic, pleomorphic, branching, non-motile, non-sporulating, non-a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SRP RNA
The signal recognition particle RNA, (also known as 7SL, 6S or 4.5S RNA) is part of the signal recognition particle (SRP) ribonucleoprotein complex. SRP recognizes the signal peptide and binds to the ribosome, halting protein synthesis. Signal recognition particle receptor, is a protein that is embedded in a membrane, and which contains a Transmembrane channels, transmembrane pore. When the complex binds to , SRP releases the ribosome and drifts away. The ribosome resumes protein synthesis, but now the protein is moving through the transmembrane pore. In this way SRP directs the movement of proteins within the Cell (biology), cell to bind with a transmembrane pore which allows the protein to cross the membrane to where it is needed. The RNA and protein components of this complex are highly Conserved sequence, conserved but do vary between the different Kingdom (biology), kingdoms of life. The common Short interspersed nuclear element, SINE family Alu sequence, Alu probably or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytosine
Cytosine () ( symbol C or Cyt) is one of the four nucleobases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA). It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at position 2). The nucleoside of cytosine is cytidine. In Watson-Crick base pairing, it forms three hydrogen bonds with guanine. History Cytosine was discovered and named by Albrecht Kossel and Albert Neumann in 1894 when it was hydrolyzed from calf thymus tissues. A structure was proposed in 1903, and was synthesized (and thus confirmed) in the laboratory in the same year. In 1998, cytosine was used in an early demonstration of quantum information processing when Oxford University researchers implemented the Deutsch-Jozsa algorithm on a two qubit nuclear magnetic resonance quantum computer (NMRQC). In March 2015, NASA scientists reported the formation of cytosine, along with uracil and thym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guanine
Guanine () ( symbol G or Gua) is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine (uracil in RNA). In DNA, guanine is paired with cytosine. The guanine nucleoside is called guanosine. With the formula C5H5N5O, guanine is a derivative of purine, consisting of a fused pyrimidine-imidazole ring system with conjugated double bonds. This unsaturated arrangement means the bicyclic molecule is planar. Properties Guanine, along with adenine and cytosine, is present in both DNA and RNA, whereas thymine is usually seen only in DNA, and uracil only in RNA. Guanine has two tautomeric forms, the major keto form (see figures) and rare enol form. It binds to cytosine through three hydrogen bonds. In cytosine, the amino group acts as the hydrogen bond donor and the C-2 carbonyl and the N-3 amine as the hydrogen-bond acceptors. Guanine has the C-6 carbonyl group that acts as the hydrogen bond acceptor, while a group at N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Signal Recognition Particle RNA
The signal recognition particle RNA, (also known as 7SL, 6S or 4.5S RNA) is part of the signal recognition particle (SRP) ribonucleoprotein complex. SRP recognizes the signal peptide and binds to the ribosome, halting protein synthesis. Signal recognition particle receptor, is a protein that is embedded in a membrane, and which contains a Transmembrane channels, transmembrane pore. When the complex binds to , SRP releases the ribosome and drifts away. The ribosome resumes protein synthesis, but now the protein is moving through the transmembrane pore. In this way SRP directs the movement of proteins within the Cell (biology), cell to bind with a transmembrane pore which allows the protein to cross the membrane to where it is needed. The RNA and protein components of this complex are highly Conserved sequence, conserved but do vary between the different Kingdom (biology), kingdoms of life. The common Short interspersed nuclear element, SINE family Alu sequence, Alu probably or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Promoter (biology)
In genetics, a promoter is a sequence of DNA to which proteins bind to initiate transcription of a single RNA transcript from the DNA downstream of the promoter. The RNA transcript may encode a protein (mRNA), or can have a function in and of itself, such as tRNA or rRNA. Promoters are located near the transcription start sites of genes, upstream on the DNA (towards the 5' region of the sense strand). Promoters can be about 100–1000 base pairs long, the sequence of which is highly dependent on the gene and product of transcription, type or class of RNA polymerase recruited to the site, and species of organism. Promoters control gene expression in bacteria and eukaryotes. RNA polymerase must attach to DNA near a gene for transcription to occur. Promoter DNA sequences provide an enzyme binding site. The -10 sequence is TATAAT. -35 sequences are conserved on average, but not in most promoters. Artificial promoters with conserved -10 and -35 elements transcribe more slowly. All D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retinoic Acid
Retinoic acid (used simplified here for all-''trans''-retinoic acid) is a metabolite of vitamin A1 (all-''trans''-retinol) that mediates the functions of vitamin A1 required for growth and development. All-''trans''-retinoic acid is required in chordate animals, which includes all higher animals from fish to humans. During early embryonic development, all-''trans''-retinoic acid generated in a specific region of the embryo helps determine position along the embryonic anterior/posterior axis by serving as an intercellular signaling molecule that guides development of the posterior portion of the embryo. It acts through Hox genes, which ultimately control anterior/posterior patterning in early developmental stages. All-''trans''-retinoic acid (ATRA) is the major occurring retinoic acid, while isomers like 13-''cis''- and 9-''cis''-retinoic acid are also present in much lower levels. The key role of all-''trans''-retinoic acid in embryonic development mediates the high teratogenici ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Polymerase III
In eukaryote cells, RNA polymerase III (also called Pol III) is a protein that transcribes DNA to synthesize ribosomal 5S rRNA, tRNA and other small RNAs. The genes transcribed by RNA Pol III fall in the category of "housekeeping" genes whose expression is required in all cell types and most environmental conditions. Therefore, the regulation of Pol III transcription is primarily tied to the regulation of cell growth and the cell cycle, thus requiring fewer regulatory proteins than RNA polymerase II. Under stress conditions however, the protein Maf1 represses Pol III activity. Rapamycin is another Pol III inhibitor via its direct target TOR. Transcription The process of transcription (by any polymerase) involves three main stages: *Initiation, requiring construction of the RNA polymerase complex on the gene's promoter *Elongation, the synthesis of the RNA transcript *Termination, the finishing of RNA transcription and disassembly of the RNA polymerase complex Initiation In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRNA
Transfer RNA (abbreviated tRNA and formerly referred to as sRNA, for soluble RNA) is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length (in eukaryotes), that serves as the physical link between the mRNA and the amino acid sequence of proteins. tRNAs genes from Bacteria are typically shorter (mean = 77.6 bp) than tRNAs from Archaea (mean = 83.1 bp) and eukaryotes (mean = 84.7 bp). The mature tRNA follows an opposite pattern with tRNAs from Bacteria being usually longer (median = 77.6 nt) than tRNAs from Archaea (median = 76.8 nt), with eukaryotes exhibiting the shortest mature tRNAs (median = 74.5 nt). Transfer RNA (tRNA) does this by carrying an amino acid to the protein synthesizing machinery of a cell called the ribosome. Complementation of a 3-nucleotide codon in a messenger RNA (mRNA) by a 3-nucleotide anticodon of the tRNA results in protein synthesis based on the mRNA code. As such, tRNAs are a necessary component of translation, the biological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleic Acid Notation
The nucleic acid notation currently in use was first formalized by the International Union of Pure and Applied Chemistry (IUPAC) in 1970. This universally accepted notation uses the Roman characters G, C, A, and T, to represent the four nucleotides commonly found in deoxyribonucleic acids (DNA). Given the rapidly expanding role for genetic sequencing, synthesis, and analysis in biology, some researchers have developed alternate notations to further support the analysis and manipulation of genetic data. These notations generally exploit size, shape, and symmetry to accomplish these objectives. IUPAC notation Degenerate base symbols in biochemistry are an IUPAC representation for a position on a DNA sequence that can have multiple possible alternatives. These should not be confused with non-canonical bases because each particular sequence will have in fact one of the regular bases. These are used to encode the consensus sequence of a population of aligned sequences and are used f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BC200 LncRNA
Brain cytoplasmic 200 long-noncoding RNA (or BC200 lncRNA) is a 200 nucleotide RNA transcript found predominantly in the brain with a primary function of regulating translation by inhibiting its initiation. As a long non-coding RNA, it belongs to a family of RNA transcripts that are not translated into protein ( ncRNAs). Of these ncRNAs, lncRNAs are transcripts of 200 nucleotides or longer and are almost three times more prevalent than protein-coding genes. Nevertheless, only a few of the almost 60,000 lncRNAs have been characterized, and little is known about their diverse functions (transcriptional interference, chromatin remodeling, splicing, translation regulation, interaction with miRNAs and siRNAs, and mRNA degradation). BC200 is one lncRNA that has given insight into their specific role in translation regulation, and implications in various forms of cancer as well as Alzheimer's disease. The accepted gene symbol for the BC200-coding gene is BCYRN1, for Brain cytoplasmic RN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
