| U6 small nuclear RNA methyltransferase | <enzyme> Methylates gamma-phosphate residues in rnas; distinct from u6 snrna n6-adenosine methyltranferase; mw 130 kD; from hela cells Registry number: EC 2.1.1.- Synonym: u6 snrna capping enzyme (26 Jun 1999) |
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| U1 small nuclear RNA-(guanosine-N2)-methyltransferase | <enzyme> A trans-active non-small nuclear ribonucleoprotein; facilitates the formation of the m3g cap Registry number: EC 2.1.1.- Synonym: u1 snrna(g-n2)mtase (26 Jun 1999) |
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| RNA, small nuclear | Short chains of RNA found in the nucleus. Their function is to remove the introns (nontranslated intervening sequences) from mRNA precursors, thereby bringing the two exons (coding segments) together into correct juxtaposition for enzymatic splicing at the correct point. The resulting mRNA is now ready to leave the nucleus. (12 Dec 1998) |
| small nuclear 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) |
| ribonucleoproteins, small nuclear | Highly conserved nuclear RNA-protein complexes that function in RNA processing in the nucleus, including pre-mRNA splicing and pre-mRNA 3'-end processing in the nucleoplasm. The u3 snrnp is localised in the nucleolus, where it aligns into base pairs with the 28s rrna precursor in a still unidentified region and functions in pre-rrna processing. The u7 snrnp aligns into base pairs with a conserved sequence in the 3'-end of histone pre-mRNA and is an essential cofactor for the cleavage that creates the mature nonadenylated 3'-end. (12 Dec 1998) |
| RNA, heterogeneous nuclear | Nuclear nonribosomal RNA larger than about 1000 nucleotides, the mass of which is rapidly synthesised and degraded within the cell nucleus. Some heterogeneous nuclear RNA may be a precursor to mRNA. However, the great bulk of total hnrna hybridises with nuclear DNA rather than with mRNA. (12 Dec 1998) |
| RNA, nuclear | RNA molecules found in the nucleus either associated with chromosomes or in the nucleoplasm. (12 Dec 1998) |
| heterogeneous nuclear 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) |
| heterogenous nuclear RNA | <molecular biology> Originally identified as a class of RNA, found in the nucleus but not the nucleolus, which is rapidly labelled and with a very wide range of sizes, 2-40 kilobases. It represents the primary transcripts of RNA polymerase II and includes precursors of all messenger RNAs from which introns are removed by splicing. (18 Nov 1997) |
| nuclear RNA | <molecular biology> The nucleus contains RNA that has just been synthesised, but in addition there is some that seems not to be released or is only released after further processing, the heterogenous nuclear RNA (hnRNA) and small RNA molecules associated with protein to form small nuclear ribonucleoproteins. (18 Nov 1997) |
| 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) |
| 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) |
| bilaterally small, smooth kidneys | <radiology> Generalised atherosclerosis, nephrosclerosis - benign and malignant, atheroembolic renal disease, chronic glomerulonephritis, papillary necrosis, hereditary diseases, hereditary chronic nephritis (Alport's syndrome), medullary cystic disease, amyloidosis (late), arterial hypotension Cf: other urographic patterns (12 Dec 1998) |
| carcinoma, non-small-cell lung | A heterogeneous aggregate of at least three distinct histological types of lung cancer, including squamous cell carcinoma, adenocarcinoma, and large cell carcinoma. They are dealt with collectively because of the shared properties of poor response to conventional chemotherapy and the potential for cure with surgical resection in a fraction of patients. (12 Dec 1998) |
| carcinoma, small cell | An anaplastic, highly malignant, and usually bronchogenic carcinoma composed of small ovoid cells with scanty neoplasm. It is characterised by a dominant, deeply basophilic nucleus, and absent or indistinct nucleoli. There are admixtures of small cell lung carcinoma with other types of lung cancer. Small cell carcinomas are distinguished by their distinctive biological features, response to chemotherapy and radiotherapy, and by their nearly universal tendency to develop overt or subclinical metastases, which frequently eliminates surgery in most patients. (12 Dec 1998) |