cis‐Effect of DnaJ on DnaK in ternary complexes with chimeric DnaK/DnaJ‐binding peptides

FEBS Letters

Christen, Philipp¹  Han, Wanjiang¹ 

[1] Biochemisches Institut der Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland

关键词: Molecular chaperone;    Hsp70;    Hsp40;    DnaK;    DnaJ;    Chimeric DnaK/DnaJ-binding peptides;    Hsp70;    70-kDa heat shock protein;    Hsp40;    40-kDa heat shock protein;    acrylodan;    6-acryloyl-2-dimethylaminonaphthalene;    a-;    acrylodan-labeled;   

DOI  :  10.1016/S0014-5793(04)00290-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Chimeric peptides, comprising a DnaK-binding sequence of L-amino acid residues (motif k) and an exclusive DnaJ-binding sequence of D-amino acid residues (motif j) connected through a 22-residue linker, were examined as minisubstrates for the DnaK chaperone system. The DnaJ-stimulated ATPase activity of DnaK was three times higher in the presence of the chimeric peptides pjk or pkj than in the simultaneous presence of the corresponding single-motif peptides ala-p5 (k motif) plus D-p5 (j motif). Apparently, pjk and pkj mimic unfolded proteins by forming ternary (ATP·DnaK)·peptide·DnaJ complexes which favor cis-interaction of DnaJ with DnaK. Consistent with this interpretation, the specific stimulatory effect of the chimeric peptides was abolished by either single-motif peptide in excess.

【 授权许可】

Unknown