Primase
| dnaG ( E. coli ) | ||
|---|---|---|
|
||
| dnaG ligament / surface model according to PDB 3B39 | ||
| Mass / length primary structure | 581 amino acids | |
| Secondary to quaternary structure | Monomer | |
| Cofactor | Zn 2+ | |
| Identifier | ||
| External IDs |
|
|
| Enzyme classification | ||
| EC, category | 2.7.7. , Nucleotidyl transferase | |
| Response type | Nucleotide addition | |
| Substrate | Nucleoside triphosphate + RNA n | |
| Products | Diphosphate + RNA n + 1 | |
| Occurrence | ||
| Homology family | DNA primase | |
| Parent taxon | bacteria | |
Primase is the name for an RNA polymerase , i.e. an enzyme . Primases are components of primosomes (Ssb protein + helicase + primase) that play a role in initiating the duplication of genetic material .
The primase generates a short RNA starter molecule, the primer . This primer attaches to the complementary sequence on the DNA . The resulting piece of double strand is used by the DNA polymerase as a starting point for the extension ( elongation ) of the DNA strand.
The primase of the prokaryotes is the DnaG protein. In eukaryotes , the primase consists of two subunits that, as part of the DNA polymerase α, do the priming.
literature
- Bocquier, Arnaud A. (2001). "Archaeal primase". Current biology 11 (6): 452-456.
- Griep, Mark A. (1995). "Primase Structure and Function". Indian Journal of Biochemistry & Biophysics 32 (4): 171-8. PMID 8655184 .
- Keck, James L., and Daniel D. Roche, A. Simon Lynch, James M. Berger. (2000). "Structure of the RNA Polymerase Domain of E. coli Primase". Science 282 (5462): 2482-6. doi : 10.1126 / science.287.5462.2482 . PMID 10741967 .
- Lee, Jong-Bong, and Richard K. Hite, Samir M. Hamdan, et al. (2006). "DNA primase acts as a molecular brake in DNA replication". Nature 439 (7076): 621-624. doi : 10.1038 / nature04317 . PMID 16452983 .
- Cavanaugh, Nisha A., and Robert D. Kuchta (2009). "Initiation of New DNA Strands by the Herpes Simplex Virus-1 Primase-Helicase Complex and Either Herpes DNA Polymerase or Human DNA Polymerase alpha". J. Biol. Chem. 284 (3): 1523-1532. doi : 10.1074 / jbc.M805476200 . PMC 2615532 (free full text). PMID 19028696 .