Poly (A) polymerase
| Poly (A) polymerase alpha | ||
|---|---|---|
| Properties of human protein | ||
| Mass / length primary structure | 744 amino acids | |
| Secondary to quaternary structure | Monomer | |
| Isoforms | 2 | |
| Identifier | ||
| Gene name | PAPOLA | |
| External IDs | ||
| Enzyme classification | ||
| EC, category | 2.7.7.19 , nucleotidyl transferase | |
| Response type | Polyadenylation | |
| Substrate | ATP + RNA (n) | |
| Products | Diphosphate + RNA (n + 1) | |
| Occurrence | ||
| Homology family | Poly (A) polymerase | |
| Parent taxon | Eukaryotes | |
The poly (A) polymerase (PAP-α) is an enzyme that the post-transcriptional polyadenylation of newly synthesized pre-mRNA in the nucleus of eukaryotic catalyzed.
The human PAP-α is found in the cell nucleus as well as in the cytosol .
The activity of PAP-α is regulated by its (de) phosphorylation and by binding of other proteins, in particular CPSF and Fip1 . This type of regulation is an approach to the unspecific control of gene expression . The hyperphosphorylation of PAP-α by the mitosis-promoting factor leads to a shutdown of translation in the metaphase of meiosis II. On the other hand, the VPR protein of the HI virus, for example, dephosphorylates PAP-α and thus leads to increased translation of virus proteins.
Individual evidence
- ↑ a b UniProt P51003
- ↑ DF Colgan, KG Murthy, W. Zhao, C. Prives, JL Manley: Inhibition of poly (A) polymerase requires p34cdc2 / cyclin B phosphorylation of multiple consensus and non-consensus sites. In: EMBO J . 17 (4), Feb 16, 1998, pp. 1053-1062. PMID 9463383
- ↑ AJ Mouland, M. Coady, XJ Yao, EA Cohen: Hypophosphorylation of poly (A) polymerase and increased polyadenylation activity are associated with human immunodeficiency virus type 1 Vpr expression. In: Virology. 292 (2), Jan 20, 2002, pp. 321-330. PMID 11878934
- ↑ H. Kim, JH Lee, Y. Lee: Regulation of poly (A) polymerase by 14-3-3epsilon. In: EMBO J. 22 (19), Oct 1, 2003, pp. 5208-5219. PMID 14517258
- ^ I. Kaufmann, G. Martin, A. Friedlein, H. Langen, W. Keller: Human Fip1 is a subunit of CPSF that binds to U-rich RNA elements and stimulates poly (A) polymerase. In: EMBO J. 23 (3), Feb 11, 2004, pp. 616-626. Epub 2004 Jan 29. PMID 14749727
Web links
- reactome: mRNA polyadenylation
- David Goodsell: Molecule of the Month: Poly (A) Polymerase - doi : 10.2210 / rcsb_pdb / mom_2008_10