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SUMOylation of nuclear actin.

ABSTRACT: Actin, a major component of the cytoplasm, is also abundant in the nucleus. Nuclear actin is involved in a variety of nuclear processes including transcription, chromatin remodeling, and intranuclear transport. Nevertheless, the regulation of nuclear actin by posttranslational modifications has not been investigated. We now show that nuclear actin is modified by SUMO2 and SUMO3 and that computational modeling and site-directed mutagenesis identified K68 and K284 as critical sites for SUMOylating actin. We also present a model for the actin-SUMO complex and show that SUMOylation is required for the nuclear localization of actin.

SUBMITTER: Hofmann WA

PROVIDER: S-EPMC2717643 | biostudies-literature | 2009 Jul

REPOSITORIES: biostudies-literature

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SUMOylation of nuclear actin.

Hofmann Wilma A WA Arduini Alessandro A Nicol Samantha M SM Camacho Carlos J CJ Lessard James L JL Fuller-Pace Frances V FV de Lanerolle Primal P

The Journal of cell biology 20090701 2

Actin, a major component of the cytoplasm, is also abundant in the nucleus. Nuclear actin is involved in a variety of nuclear processes including transcription, chromatin remodeling, and intranuclear transport. Nevertheless, the regulation of nuclear actin by posttranslational modifications has not been investigated. We now show that nuclear actin is modified by SUMO2 and SUMO3 and that computational modeling and site-directed mutagenesis identified K68 and K284 as critical sites for SUMOylating ...[more]

PMID: 19635839

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