Structure of small G proteins and their regulators

• Autorzy: Paduch M. , Jelen F. , Otlewski J.
• Języki publikacji: EN

Abstrakty

EN

In recent years small G proteins have become an intensively studied group of regula­tory GTP hydrolases involved in cell signaling. More than 100 small G proteins have been identified in eucaryotes from protozoan to human. The small G protein superfamily includes Ras, Rho Rab, Rac, Sar1/Arf and Ran homologs, which take part in numerous and diverse cellular processes, such as gene expression, cytoskeleton re­organization, microtubule organization, and vesicular and nuclear transport. These proteins share a common structural core, described as the G domain, and significant sequence similarity. In this paper we review the available data on G domain structure, together with a detailed analysis of the mechanism of action. We also present small G protein regulators: GTPase activating proteins that bind to a catalytic G domain and increase its low intrinsic hydrolase activity, GTPase dissociation inhibitors that stabi­lize the GDP-bound, inactive state of G proteins, and guanine nucleotide exchange fac­tors that accelerate nucleotide exchange in response to cellular signals. Additionally, in this paper we describe some aspects of small G protein interactions with down­stream effectors.

Słowa kluczowe

EN

cellular signalling; G protein; man; vesicular transport; microtubule organization; gene expression; protein tertiary structure; nuclear transport; regulator; GTPase; cytoskeleton reorganization; small G protein

• Wydawca: -
• Czasopismo: Acta Biochimica Polonica
• Rocznik: 2001
• Tom: 48
• Numer: 4
• Opis fizyczny: p.829-850,fig.

Twórcy

autor

Paduch M.

• University of Wroclaw, Tamka 2, 50-137 Wroclaw, Poland

autor

Jelen F.

autor

Otlewski J.

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