ATP介导的RecA蛋白中跨亚基相互作用的变化。

ATP-mediated changes in cross-subunit interactions in the RecA protein.

作者信息

Logan K M, Forget A L, Verderese J P, Knight K L

机构信息

Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655-0103, USA.

出版信息

Biochemistry. 2001 Sep 25;40(38):11382-9. doi: 10.1021/bi011081u.

DOI:10.1021/bi011081u

PMID:11560486

Abstract

RecA protein undergoes ATP- and DNA-induced conformational changes that result in different helical parameters for free protein filaments versus RecA/ATP/DNA nucleoprotein filaments. Previous mutational studies of a particular region of the RecA oligomeric interface suggested that cross-subunit contacts made by residues K6 and R28 were more important for stabilization of free protein oligomers than nucleoprotein filaments [Eldin, S., et al. (2000) J. Mol. Biol. 299, 91-101]. Using mutant proteins with specifically engineered Cys substitutions, we show here that the efficiency of cross-subunit disulfide bond formation at certain positions in this region changes in the presence of ATP or ATP/DNA. Our results support the idea that specific cross-subunit interactions that occur within this region of the subunit interface are different in free RecA protein versus RecA/ATP/DNA nucleoprotein filaments.

摘要

RecA蛋白会经历由ATP和DNA诱导的构象变化，这导致游离蛋白丝与RecA/ATP/DNA核蛋白丝具有不同的螺旋参数。先前对RecA寡聚体界面特定区域的突变研究表明，K6和R28残基形成的亚基间接触对于游离蛋白寡聚体的稳定比核蛋白丝更为重要[埃尔丁，S.等人（2000年）《分子生物学杂志》299卷，91 - 101页]。我们在此使用具有特定工程化半胱氨酸取代的突变蛋白表明，在该区域某些位置形成亚基间二硫键的效率在ATP或ATP/DNA存在时会发生变化。我们的结果支持这样一种观点，即亚基界面该区域内发生的特定亚基间相互作用在游离RecA蛋白与RecA/ATP/DNA核蛋白丝中是不同的。