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Dictyostelium dynamin B modulates cytoskeletal structures and membranous organelles.

ABSTRACT: Dictyostelium discoideum cells produce five dynamin family proteins. Here, we show that dynamin B is the only member of this group of proteins that is initially produced as a preprotein and requires processing by mitochondrial proteases for formation of the mature protein. Our results show that dynamin B-depletion affects many aspects of cell motility, cell-cell and cell-surface adhesion, resistance to osmotic shock, and fatty acid metabolism. The mature form of dynamin B mediates a wide range and unique combination of functions. Dynamin B affects events at the plasma membrane, peroxisomes, the contractile vacuole system, components of the actin-based cytoskeleton, and cell adhesion sites. The modulating effect of dynamin B on the activity of the contractile vacuole system is unique for the Dictyostelium system. Other functions displayed by dynamin B are commonly associated with either classical dynamins or dynamin-related proteins.

SUBMITTER: Rai A

PROVIDER: S-EPMC3142549 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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Dictyostelium dynamin B modulates cytoskeletal structures and membranous organelles.

Rai Amrita A Nöthe Heike H Tzvetkov Nikolay N Korenbaum Elena E Manstein Dietmar J DJ

Cellular and molecular life sciences : CMLS 20101118 16

Dictyostelium discoideum cells produce five dynamin family proteins. Here, we show that dynamin B is the only member of this group of proteins that is initially produced as a preprotein and requires processing by mitochondrial proteases for formation of the mature protein. Our results show that dynamin B-depletion affects many aspects of cell motility, cell-cell and cell-surface adhesion, resistance to osmotic shock, and fatty acid metabolism. The mature form of dynamin B mediates a wide range a ...[more]

PMID: 21086149

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