Caenorhabditis elegans small heat‐shock proteins Hsp12.2 and Hsp12.3 form tetramers and have no chaperone‐like activity

FEBS Letters

Kokke, Bas P.A.²  Boelens, Wilbert C.²  Candido, E.Peter M.¹  de Jong, Wilfried W.²  Leroux, Michel R.¹ 

[1] Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada;Department of Biochemistry, University of Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands

关键词: Small heat-shock protein;    Molecular chaperone;    Caenorhabditis elegans;    sHSP;    small heat-shock protein;    rec-;    recombinant;    SP buffer;    sodium phosphate buffer;    DDT;    dithiothreitol;    CD;    circular dichroism;    BSA;    bovine serum albumin;   

DOI  :  10.1016/S0014-5793(98)00917-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Four 12.2–12.6 kDa small heat-shock proteins (sHSPs) of Caenorhabditis elegans are the smallest known members of the sHSP family. They essentially comprise the characteristic C-terminal ‘α-crystallin domain’ of the sHSPs, having a very short N-terminal region, and lacking a C-terminal tail. Recombinant Hsp12.2 and 12.3 are characterized here. FarUV CD spectra reveal, as for other sHSPs, predominantly a β-sheet structure. By gel permeation and crosslinking, they are the first sHSPs shown to occur as tetramers, rather than forming the usual large multimeric complexes. Exceptionally, too, both appear devoid of in vitro chaperone-like abilities. This supports the notion that tetramers are the building blocks of sHSP complexes, and that higher multimer formation, mediated through the N-terminal domains, is a prerequisite for chaperone-like activity.

【 授权许可】

Unknown