| DNA, ribosomal | DNA sequences encoding ribosomal RNA. These sequences regulate amplification and transcription initiation and contain transcribed and nontranscribed spacer segments. (12 Dec 1998) |
|---|---|
| 60S ribosomal protein kinase | <enzyme> Phosphorylates 60s ribosomal proteins l44, l44', l45 and a 38 kD protein from the 60s subunit only on serine residues Registry number: EC 2.7.10.- (26 Jun 1999) |
| frameshifting, ribosomal | A directed change in translational reading frame that allows the production of a single protein from two or more overlapping genes. The process is programmed by the nucleotide sequence of the mRNA and is sometimes also affected by the secondary or tertiary mRNA structure. It has been described mainly in viruses (especially retroviruses), retrotransposons, and bacterial insertion elements but also in some cellular genes. (12 Dec 1998) |
| acceptor RNA | rNA |
| antisense RNA | <molecular biology> A complementary RNA sequence that binds to (and thus blocks the transcription of) a naturally-occuring (sense) messenger RNA molecule. These proteins can be used to selectively turn off production of certain proteins or block viral genetic instructions, by marking them for destruction by cellular enzymes, in order to prevent the building of new virus or the infection of new cells. (09 Oct 1997) |
| bacteriophage T3 RNA polymerase | <enzyme> Used for the rapid generation of strand-specific RNA molecules that can be used for the identification of genes in hybridization experiments Registry number: EC 2.7.7.- Synonym: t3 RNA polymerase (26 Jun 1999) |
| cap II RNA(nucleoside-2'-)methyltransferase | <enzyme> Converts cap i-terminated mRNA to cap II-terminated mRNA Registry number: EC 2.1.1.- Synonym: cap II methylase (26 Jun 1999) |
| cap I RNA (nucleoside-2'-)methyltransferase | <enzyme> Converts cap 0-terminated mRNA to cap i-terminated mRNA Registry number: EC 2.1.1.- Synonym: cap I methylase (26 Jun 1999) |
| p68 RNA helicase | <enzyme> An RNA helicase isolated from uv-induced tumours in mice; amino acid sequence has been determined Registry number: EC 2.7.7.- Synonym: dead box helicase p68 (26 Jun 1999) |
| masked messenger RNA | <molecular biology> Long lived and stable mRNA found originally in the oocytes of echinoderms and constituting a store of maternal information for protein synthesis that is unmasked (derepressed) during the early stages of morphogenesis. In these early stages the rate of cell division is so rapid that transcription from the embryonic genome cannot occur. Undoubtedly not restricted to oocytes and the term can be applied to any mRNA which is present in inactive form. (18 Nov 1997) |
| messenger-like RNA | An ill-defined form of RNA, of high molecular weight, that never leaves the nucleus and is thought to be the precursor of messenger RNA. (05 Mar 2000) |
| messenger RNA | <molecular biology> Single stranded RNA molecule that specifies the amino acid sequence of one or more polypeptide chains. This information is translated during protein synthesis when ribosomes bind to the mRNA. In prokaryotes, mRNA is normally formed by splicing a large primary transcript from a DNA sequence and protein synthesis starts while the mRNA is still being synthesised. Prokaryote mRNAs are usually very short lived (average t 1/2 is 5mins.). In contrast, in eukaryotes the primary transcripts (HnRNA) are synthesised in the nucleus and they are extensively processed to give the mRNA that is exported to the cytoplasm where protein synthesis takes place. This processing includes the addition of a 5' 5' linked 7 methyl guanylate cap at the 5' end and a sequence of adenylate groups at the 3' end, the poly A tail, as well as the removal of any introns and the splicing together of exons, only 10% of HnRNA leaves the nucleus. Eukaryote mRNAs are comparatively long lived with a half life ranging from 30minutes to 24 hours. (27 Jun 1999) |
| GTP-RNA guanylyltransferase | <enzyme> Catalyses addition of GMP residue to 3'-ends of oligonucleotide primers Registry number: EC 2.7.7.- Synonym: terminal guanylyltransferase (26 Jun 1999) |
| RNA | <molecular biology> A nucleic acid found in all living cells. Plays a role in transferring information from DNA to the protein-forming system of the cell. (16 Dec 1997) |
| RNA 2'-O-methyltransferase | <enzyme> Methylates 2'-hydroxyl group of ribose moieties of ribosomal RNA; highest activity poly (c) is a synthetic substrate Registry number: EC 2.1.1.- Synonym: nucleolar 2'-o-methyltransferase (26 Jun 1999) |