Mitochondrial presequences can induce aggregation of unfolded proteins

FEBS Letters

Mitsui, Satoko¹  Endo, Toshiya¹  Roise, David² 

[1]Department of Chemistry, Faculty of Science, Nagoya University, Chikusa-ku, Nagoya 464-01, Japan

[2]Department of Chemistry and Biochemistry, University of California at San Diego, La Jolla, CA 92093-0506, USA

关键词: Mitochondrial presequence;    Protein aggregation;    Unfolded protein;    Mitochondrial precursor protein;    RCM-LA;    reduced carboxymethylated bovine α-lactalbumin;    E.coli;    Escherichia coli;    pF1b;    the precursor form of the β subunit of F1-ATPase;    DTT;    dithiothreitol;    R-LA;    reduced bovine α-lactalbumin;    DHFR;    mouse dihydrofolate reductase;    PBF;    a presequence-binding factor;    MSF;    mitochondrial import stimulation factor;   

DOI  :  10.1016/0014-5793(95)00015-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have studied the interactions between various synthetic peptides and two model unfolded proteins, reduced α-lactalbumin and reduced and carboxymethylated α-lactalbumin. We found that mitochondrial presequences could induce aggregation of the unfolded α-lactalbumins but not of the native α-lactalbumin. The presequence-induced aggregation of unfolded α-lactalbumin was dependent on electrostatic interactions and on the amphiphilicity of the presequences. Since positive charge and amphiphilicity are necessary for the targeting function of mitochondrial presequences, presequence-induced aggregation may be responsible for the instability of mitochondrial precursor proteins and may need to be inhibited by binding factors in the cytosol.

【 授权许可】

Unknown