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Sumoylation of Drosophila SU(VAR)3-7 is required for its heterochromatic function.

ABSTRACT: In Drosophila, SU(VAR)3-7 is an essential heterochromatin component. It is required for proper chromatin condensation, and changing its dose modifies position-effect variegation. Sumoylation is a post-translational modification shown to play a role in diverse biological processes. Here, we demonstrate that sumoylation is essential for proper heterochromatin function in Drosophila through modification of SU(VAR)3-7. Indeed, SU(VAR)3-7 is sumoylated at lysine K839; this modification is required for localization of SU(VAR)3-7 at pericentric heterochromatin, chromosome 4, and telomeres. In addition, sumoylation of SU(VAR)3-7 is a prerequisite for its ability to enhance position-effect variegation. Thus, these results show that the heterochromatic function of SU(VAR)3-7 depends on its own sumoylation, and unveil a role for sumoylation in Drosophila heterochromatin.

SUBMITTER: Reo E

PROVIDER: S-EPMC2910048 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature

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Sumoylation of Drosophila SU(VAR)3-7 is required for its heterochromatic function.

Reo Emanuela E Seum Carole C Spierer Pierre P Bontron Séverine S

Nucleic acids research 20100318 13

In Drosophila, SU(VAR)3-7 is an essential heterochromatin component. It is required for proper chromatin condensation, and changing its dose modifies position-effect variegation. Sumoylation is a post-translational modification shown to play a role in diverse biological processes. Here, we demonstrate that sumoylation is essential for proper heterochromatin function in Drosophila through modification of SU(VAR)3-7. Indeed, SU(VAR)3-7 is sumoylated at lysine K839; this modification is required fo ...[more]

PMID: 20299342

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