1zt2
From Proteopedia
Heterodimeric structure of the core primase.
Structural highlights
FunctionPRIS_SACS2 Catalytic subunit of DNA primase, an RNA polymerase that catalyzes the synthesis of short RNA molecules used as primers for DNA polymerase during DNA replication. The small subunit contains the primase catalytic core and has DNA synthesis activity on its own. Binding to the large subunit stabilizes and modulates the activity, increasing the rate of DNA synthesis while decreasing the length of the DNA fragments, and conferring RNA synthesis capability. The DNA polymerase activity may enable DNA primase to also catalyze primer extension after primer synthesis. May also play a role in DNA repair. Possesses a template-independent 3'-terminal nucleotidyl transferase activity.[HAMAP-Rule:MF_00700][1] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedPrimases are DNA-dependent RNA polymerases that synthesize the oligoribonucleotide primers essential to DNA replication. In archaeal and eukaryotic organisms, the core primase is a heterodimeric enzyme composed of a small and a large subunit. Here we report a crystallographic and biochemical analysis of the core primase from the archaeon Sulfolobus solfataricus. The structure provides the first three-dimensional description of the large subunit and its interaction with the small subunit. The evolutionary conservation of amino acids at the protein-protein interface implies that the observed mode of subunit association is conserved among archaeal and eukaryotic primases. The orientation of the large subunit in the core primase probably excludes its direct involvement in catalysis. Modeling of a DNA-RNA helix together with structure-based site-directed mutagenesis provides insight into the mechanism of template DNA binding and RNA primer synthesis. Structure of the heterodimeric core primase.,Lao-Sirieix SH, Nookala RK, Roversi P, Bell SD, Pellegrini L Nat Struct Mol Biol. 2005 Dec;12(12):1137-44. Epub 2005 Nov 6. PMID:16273105[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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