Structure of small G proteins and their regulators.

• Authors: Marcin Paduch , Filip Jeleń , Jacek Otlewski
• Languages of publication: EN

Abstracts

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.

Keywords

EN

small G protein; GAP; protein-protein interaction; GTPase; GDI; Rho; Ras; protein tertiary structure; GEF

• Publisher: Polish Biochemical Society
• Journal: Acta Biochimica Polonica
• Year: 2001
• Volume: 48
• Issue: 4
• Pages: 829-850

Dates

published

2001

accepted

2001-11-27

received

2001-11-6

Contributors

author

Marcin Paduch

• Institute of Biochemistry and Molecular Biology, University of Wrocław, Wrocław, Poland

author

Filip Jeleń

• Institute of Biochemistry and Molecular Biology, University of Wrocław, Wrocław, Poland

author

Jacek Otlewski

• Institute of Biochemistry and Molecular Biology, University of Wrocław, Wrocław, Poland

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