REVIEW: Structure, Properties, and Probable Physiological Role of Small Heat Shock Protein with Molecular Mass 20 kD (Hsp20, HspB6)

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N. B. Gusev^1*, O. V. Bukach¹, and S. B. Marston²

¹Department of Biochemistry, Faculty of Biology, Lomonosov Moscow State University, 119992 Moscow, Russia; fax: (7-095) 939-2747; E-mail: NBGusev@mail.ru

²Department of Cardiac Medicine, National Heart and Lung Institute, Imperial College of Science, Technology and Medicine, Dovehouse Street, London SW3 6LY, UK; E-mail: S.Marston@imperial.ac.uk

^* To whom correspondence should be addressed.

Received July 27, 2004; Revision received September 3, 2004

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This review is devoted to critical analysis of data concerning the structure and functions of small heat shock proteins with apparent molecular mass 20 kD (Hsp20). We describe the structure of Hsp20, its phosphorylation by different protein kinases, interaction of Hsp20 with other small heat shock proteins, and chaperone activity of Hsp20. The distribution of Hsp20 in different animal tissues and the factors affecting expression of Hsp20 are also described. Data on the possible involvement of Hsp20 in regulation of platelet aggregation and glucose transport are presented and analyzed. Special attention is paid to literature data describing probable regulatory effect of Hsp20 on contraction of smooth muscle. Two hypotheses postulating direct effect of Hsp20 on actomyosin interaction or its effect on cytoskeleton are compared and analyzed. The most recent data on the effect of Hsp20 on apoptosis and contractile activity of cardiomyocytes are also presented.

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KEY WORDS: small heat shock proteins, phosphorylation, chaperone activity, apoptosis, contractile activity of smooth and skeletal muscles

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