Molecular Chaperones and the Centrosome
A ROLE FOR HSP 73 IN CENTROSOMAL REPAIR FOLLOWING HEAT SHOCK TREATMENT (*)
- From the (1)Departments of Medicine and Physiology, University of California, San Francisco, California 94143 and the
- (2)Program in Molecular Medicine, University of Massachusetts Medical Center, Worcester, Massachusetts 01605
- § To whom correspondence should be addressed. Tel.: 415-206-5908; Fax: 415-206-4123.
Abstract
In the accompanying paper (Brown, C. R., Doxsey, S. J., Hong-Brown, L. W., Martin, R. L., and Welch, W. J.(1996) J. Biol. Chem. 271, 824-832) two molecular chaperones, hsp 73 and TCP-1, were shown to be integral components of the centrosome. Here we show that heat shock treatment adversely affects both the structure and function of the centrosome, and that hsp 73 plays a role in the repair of the organelle. After heat shock treatment, the centrosome could not be identified via indirect immunofluorescence and cells were unable to support microtubule regrowth. During recovery from heat shock, a strong correlation between the return of staining of three centrosomal antigens (hsp 73, TCP-1, and pericentrin) and the recovery of microtubule regrowth properties was found. Incubation of cells with glycerol, a protein protective agent, prevented the heat induced alterations in the structure/function of the centrosome. Likewise, the recovery of the structure and function of the centrosome after heat shock treatment was significantly accelerated in cells first made thermotolerant. We provide evidence that this process is related to the levels of hsp 73 since: 1) microinjection of hsp 73 antibody blocked centrosomal reassembly and microtubule regrowth abilities following heat shock; and 2) microinjection of purified hsp 73 protein prior to heat shock treatment accelerated both the repair and function of the organelle, similar to that observed for thermotolerant cells.
Footnotes
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↵* The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore by hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
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↵1 The abbreviations used are:
- Pipes
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1,4-piperazinediethanesulfonic acid
- BSA
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bovine serum albumin.
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- Received August 14, 1995.
- Revision received November 9, 1995.
- © 1996 by The American Society for Biochemistry and Molecular Biology, Inc.
