A heterotrimeric PCNA in the hyperthermophilic archaeon Sulfolobus solfataricus

被引:184
作者
Dionne, I
Nookala, RK
Jackson, SP
Doherty, AJ
Bell, SD
机构
[1] MRC, Canc Cell Unit, Hutchison Res Ctr, Cambridge CB2 2XZ, England
[2] Univ Cambridge, Cambridge Inst Med Res, Cambridge CB2 2XY, England
[3] Wellcome Canc Res UK Inst, Cambridge CB2 1QR, England
基金
英国医学研究理事会;
关键词
D O I
10.1016/S1097-2765(02)00824-9
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The sliding clamp, PCNA, of the archaeon Sulfolobus solfataricus P2 is a heterotrimer of three distinct subunits (PCNA1, 2, and 3) that assembles in a defined manner. The PCNA heterotrimer, but not individual subunits, stimulates the activities of the DNA polymerase, DNA ligase I, and the flap endonuclease (FEN1) of S. solfataricus. Distinct PCNA subunits contact DNA polymerase, DNA ligase, or FEN1, imposing a defined architecture at the lagging strand fork and suggesting the existence of a preformed scanning complex at the fork. This provides a mechanism to tightly couple DNA synthesis and Okazaki fragment maturation. Additionally, unique subunit-specific interactions between components of the clamp loader, RFC, suggest a model for clamp loading of PCNA.
引用
收藏
页码:275 / 282
页数:8
相关论文
共 19 条