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T Arm
The T-arm or T-loop is a specialized region on the tRNA molecule which acts as a special recognition site for the ribosome to form a tRNA-ribosome complex during protein biosynthesis or translation (biology). The T-arm has two components to it; the T-stem and the T-loop. * The T-stem consists of a series of paired nucleotides, typically 5 pairs, but sometimes as few as 1 or as many as 6. * The T-loop is also often known as the TΨC arm due to the presence of ribothymidine (T/m5U), pseudouridine and cytidine residues. It folds into a unique structural element consisting of stacked bases in a U-turn, now termed the "T-loop motif". ** In archaea, the m5U is replaced with N1-methylpseudouridine (m1Ψ). The m5U/m1Ψ modification at position 54 is thought to increase structural stability. Organisms with T-loop lacking tRNA exhibit a much lower level of aminoacylation and EF-Tu EF-Tu (elongation factor thermo unstable) is a prokaryotic elongation factor responsible for catalyzing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schema ARNt 448 658
Schema may refer to: Science and technology * SCHEMA (bioinformatics), an algorithm used in protein engineering * Schema (genetic algorithms), a set of programs or bit strings that have some genotypic similarity * Schema.org, a web markup vocabulary * Schema (logic) ** Axiom schema, in formal logic * Image schema, a recurring pattern of spatial sensory experience * Database schema * XML schema Other * Body schema, a neural representation of one's own bodily posture * Galant Schemata, stock phrases in Galant music * Schema (Kant), in philosophy * Schema (psychology), a mental set or representation * Schema Records, a jazz record label in Milan, Italy *, a solemn vow of asceticism of a monk in Orthodox monasticism ** Great Schema, the highest degree of Orthodox monasticism * ''Schema'' (fly), a genus of insects See also * Scheme (other) * Schematic * Skema (other) SKEMA Business School ("School of Knowledge Economy and Management") is a leading French busin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRNA
Transfer ribonucleic acid (tRNA), formerly referred to as soluble ribonucleic acid (sRNA), is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length (in eukaryotes). In a cell, it provides the physical link between the genetic code in messenger RNA (mRNA) and the amino acid sequence of proteins, carrying the correct sequence of amino acids to be combined by the protein-synthesizing machinery, the ribosome. Each three-nucleotide codon in mRNA is complemented by a three-nucleotide anticodon in tRNA. As such, tRNAs are a necessary component of translation, the biological synthesis of new proteins in accordance with the genetic code. Overview The process of translation starts with the information stored in the nucleotide sequence of DNA. This is first transformed into mRNA, then tRNA specifies which three-nucleotide codon from the genetic code corresponds to which amino acid. Each mRNA codon is recognized by a particular type of tRNA, which docks to it along ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosome
Ribosomes () are molecular machine, macromolecular machines, found within all cell (biology), cells, that perform Translation (biology), biological protein synthesis (messenger RNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA molecules to form polypeptide chains. Ribosomes consist of two major components: the small and large ribosomal subunits. Each subunit consists of one or more ribosomal RNA molecules and many ribosomal proteins (). The ribosomes and associated molecules are also known as the ''translational apparatus''. Overview The sequence of DNA that encodes the sequence of the amino acids in a protein is transcribed into a messenger RNA (mRNA) chain. Ribosomes bind to the messenger RNA molecules and use the RNA's sequence of nucleotides to determine the sequence of amino acids needed to generate a protein. Amino acids are selected and carried to the ribosome by transfer RNA (tRNA) molecules, which enter the riboso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Biosynthesis
Protein biosynthesis, or protein synthesis, is a core biological process, occurring inside Cell (biology), cells, homeostasis, balancing the loss of cellular proteins (via Proteolysis, degradation or Protein targeting, export) through the production of new proteins. Proteins perform a number of critical functions as enzymes, structural proteins or hormones. Protein synthesis is a very similar process for both prokaryotes and eukaryotes but there are some distinct differences. Protein synthesis can be divided broadly into two phases: Transcription (biology), transcription and Translation (biology), translation. During transcription, a section of DNA encoding a protein, known as a gene, is converted into a molecule called messenger RNA (mRNA). This conversion is carried out by enzymes, known as RNA polymerases, in the cell nucleus, nucleus of the cell. In eukaryotes, this mRNA is initially produced in a premature form (Primary transcript, pre-mRNA) which undergoes post-transcriptio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Translation (biology)
In biology, translation is the process in living Cell (biology), cells in which proteins are produced using RNA molecules as templates. The generated protein is a sequence of amino acids. This sequence is determined by the sequence of nucleotides in the RNA. The nucleotides are considered three at a time. Each such triple results in the addition of one specific amino acid to the protein being generated. The matching from nucleotide triple to amino acid is called the genetic code. The translation is performed by a large complex of functional RNA and proteins called ribosomes. The entire process is called gene expression. In translation, messenger RNA (mRNA) is decoded in a ribosome, outside the nucleus, to produce a specific amino acid chain, or polypeptide. The polypeptide later protein folding, folds into an Activation energy, active protein and performs its functions in the cell. The polypeptide can also start folding during protein synthesis. The ribosome facilitates decoding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribothymidine
The chemical compound 5-methyluridine (symbol m5U or m5U), also called ribothymidine (rT), is a pyrimidine nucleoside. It is the ribonucleoside counterpart to the deoxyribonucleoside thymidine, which lacks a hydroxyl group at the 2' position. 5-Methyluridine contains a thymine base joined to a ribose pentose sugar. It is a white solid. m5U is one of the most common modifications made to cellular RNA. It almost universally occurs in position 54 (part of the T arm) of eukaryotic and bacterial tRNA, serving to stabilize the molecule. The same "T-loop" motif occurs in many other forms of noncoding RNA such as tmRNA and rRNA. Loss of the tRNA modification does not usually produce a different, less fit, phenotype. See also * 5-Methylcytosine 5-Methylcytosine (5mC) is a methylation, methylated form of the DNA base cytosine (C) that regulates gene Transcription (genetics), transcription and takes several other biological roles. When cytosine is methylated, the DNA maintains the sam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudouridine
Pseudouridine (5-ribosyluracil, abbreviated by the Greek letter psi- Ψ) is an isomer of the nucleoside uridine in which the uracil is attached via a carbon-carbon instead of a nitrogen-carbon glycosidic bond. Pseudouridine is the most abundant RNA modification in cellular RNA and one of over 100 chemically distinct modifications that may affect translation or other functions of RNA. Pseudouridine is the C5-glycoside isomer of uridine that contains a C-C bond between C1 of the ribose sugar and C5 of uracil, rather than usual C1-N1 bond found in uridine. Uridine is converted to pseudouridine by rotating the uridine molecule 180° across its N3-C6 axis. The C-C bond gives it more rotational freedom and conformational flexibility. In addition, pseudouridine has an extra hydrogen bond donor at the N1 position. Pseudouridine is a ubiquitous constituent of structural RNA ( transfer (tRNA), ribosomal (rRNA), small nuclear (snRNA), and small nucleolar (snoRNA)), and present in messe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytidine
Cytidine (symbol C or Cyd) is a nucleoside molecule that is formed when cytosine is attached to a ribose ring (also known as a ribofuranose) via a β-N1-glycosidic bond. Cytidine is a component of RNA. It is a white water-soluble solid that is only slightly soluble in ethanol. Dietary sources Dietary sources of cytidine include foods with high RNA (ribonucleic acid) content, such as organ meats, brewer's yeast, as well as pyrimidine-rich foods such as beer. During digestion, RNA-rich foods are broken-down into ribosyl pyrimidines (cytidine and uridine), which are absorbed intact. In humans, dietary cytidine is converted into uridine, which is probably the compound behind cytidine's metabolic effects. Cytidine analogues A variety of cytidine analogues are known, some with potentially useful pharmacology. For example, KP-1461 is an anti-HIV agent that works as a viral mutagen, and zebularine exists in '' E. coli'' and is being examined for chemotherapy. Low doses of azacit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N1-methylpseudouridine
N1-Methylpseudouridine (abbreviated m1Ψ) is a natural archaeal tRNA component, and "hypermodified" pyrimidine nucleoside used in biochemistry and molecular biology for ''in vitro'' transcription and is found in the SARS-CoV-2 mRNA vaccines tozinameran (Pfizer–BioNTech) and elasomeran (Moderna). Properties N1-Methylpseudouridine is the methylated derivative of pseudouridine. It is used in ''in vitro'' transcription and for the production of RNA vaccines. In vertebrates, it stimulates significantly less activation of the innate immune response compared to uridine, while the translation is stronger. In protein biosynthesis, it is read like uridine and enables comparatively high protein yields. The nucleoside itself can be made by chemical methylation of pseudouridine. While pseudouridine can wobble-pair with bases other than A, work examining COVID-19 modRNA vaccines that replace all their uridines with N1-methylpseudouridine show faithful protein production. More recent w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aminoacylation
Aminoacylation is the process of adding an aminoacyl group to a compound. See also * Acylation * tRNA aminoacylation * Transfer RNA-like structures References Organic reactions {{Reaction-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elongation Factor
Elongation factors are a set of proteins that function at the ribosome, during protein synthesis, to facilitate translational elongation from the formation of the first to the last peptide bond of a growing polypeptide. Most common elongation factors in prokaryotes are EF-Tu, EF-Ts, EF-G. Bacteria and eukaryotes use elongation factors that are largely homologous to each other, but with distinct structures and different research nomenclatures. Elongation is the most rapid step in translation. In bacteria, it proceeds at a rate of 15 to 20 amino acids added per second (about 45-60 nucleotides per second). In eukaryotes the rate is about two amino acids per second (about 6 nucleotides read per second). Elongation factors play a role in orchestrating the events of this process, and in ensuring the high accuracy translation at these speeds. Nomenclature of homologous EFs In addition to their cytoplasmic machinery, eukaryotic mitochondria and plastids have their own translation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
