1t94
From Proteopedia
Crystal structure of the catalytic core of human DNA polymerase kappa
Structural highlights
Function[POLK_HUMAN] DNA polymerase specifically involved in DNA repair. Plays an important role in translesion synthesis, where the normal high-fidelity DNA polymerases cannot proceed and DNA synthesis stalls. Depending on the context, it inserts the correct base, but causes frequent base transitions, transversions and frameshifts. Lacks 3'-5' proofreading exonuclease activity. Forms a Schiff base with 5'-deoxyribose phosphate at abasic sites, but does not have lyase activity.[1] [2] [3] [4] [5] [6] [7] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedWe present the crystal structure of the catalytic core of human DNA polymerase kappa (hPolkappa), the first structure of a human Y-family polymerase. hPolkappa is implicated in the proficient extension of mispaired primer termini on undamaged DNAs, and in the extension step of lesion bypass. The structure reveals a stubby "fingers" subdomain, which despite its small size appears to be tightly restrained with respect to a putative templating base. The structure also reveals a novel "thumb" subdomain that provides a basis for the importance of the N-terminal extension unique to hPolkappa. And, most surprisingly, the structure reveals the polymerase-associated domain (PAD) juxtaposed on the dorsal side of the "palm" subdomain, as opposed to the fingers subdomain. Together, these properties suggest that the hPolkappa active site is constrained at the site of the templating base and incoming nucleotide, but the polymerase is less constrained following translocation of the lesion. Crystal structure of the catalytic core of human DNA polymerase kappa.,Uljon SN, Johnson RE, Edwards TA, Prakash S, Prakash L, Aggarwal AK Structure. 2004 Aug;12(8):1395-404. PMID:15296733[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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