| Pil., pil | Pilula; Pill; 환약 |
|---|---|
| BCP | basic calcium phosphate; birth control pill; blue cone pigment; Blue Cross Plan; bromcresol purple |
| COCP | combined oral contraceptive pill |
| OCP | octacalcium phosphate; ocular cicatricial pemphigoid; oral case presentation; oral contraceptive pil... |
| PC | avoirdupois weight [Lat. pondus civile]; packed cells; paper chromatography; paracortex; parent cell... |
| Pribnow box | <molecular biology> A region of DNA to which RNA polymerase binds before initiating the transcription of DNA into RNA. The nucleotide at which transcription starts is designated +1 and nucleotides are numbered from this with negative numbers indicating upstream nucleotides and positive downstream nucleotides. most bacterial promoters contain two consensus sequences that seem to be essential for the binding of the polymerase. The first, the Pribnow box, is at about 10 and has the consensus sequence 5' TATAAT 3'. The second, the 35 sequence, is centred about 35 and has the consensus sequence 5' TTGACA 3'. most factors that regulate gene transcription do so by binding at or near the promoter and affecting the initiation of transcription. Much less is known about eukaryote promoters, each of the three RNA polymerases has a different promoter. RNA polymerase I recognises a single promoter for the precursor of rRNA. RNA polymerase II, that transcribes all genes coding for polypeptides, recognises many thousands of promoters. most have the Goldberg Hogness or TATA box that is centred around position 25 and has the consensus sequence 5' TATAAAA 3'. Several promoters have a CAAT box around 90 with the consensus sequence 5' GGCCAATCT 3'. There is increasing evidence that all promoters for housekeeping genes contain multiple copies of a GC rich element that includes the sequence 5' GGGCGG 3'. Transcription by polymerase II is also affected by more distant elements known as enhancers. RNA polymerase III synthesises 5s ribosomal RNA, all tRNAs and a number of small RNAs. The promoter for RNA polymerase III is located within the gene either as a single sequence, as in the 5s RNA gene or as two blocks, as in all tRNA genes. (13 Nov 1997) |
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| Hogness box | <molecular biology> A consensus sequence found in the promoter region of most genes transcribed by eukaryotic RNA polymerase II. Found about 25 nucleotides before the site of initiation of transcription and has the consensus sequence: 5' TATAAAA 3'. This sequence seems to be important in determining accurately the position at which transcription is initiated. (18 Nov 1997) |
| Pu box | <molecular biology> Purine rich sequence recognised by the product of the Sp 1 oncogene. (18 Nov 1997) |
| snuff-box | See: anatomical snuffbox. (05 Mar 2000) |
| DEAD box helicase | <enzyme> Family of ATP dependent DNA or RNA helicases with a 4 amino acid consensus, D E A D, that resembles an ATP binding site. Examples, p68, a human nuclear protein involved in cell growth, vasa, a Drosophila protein required for specification of posterior embryonic structures. (18 Nov 1997) |
| TATA box | <molecular biology> A consensus sequence found in the promoter region of most genes transcribed by eukaryotic RNA polymerase II. Found about 25 nucleotides before the site of initiation of transcription and has the consensus sequence: 5' TATAAAA 3'. This sequence seems to be important in determining accurately the position at which transcription is initiated. (18 Nov 1997) |