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Hip, an HP1-interacting protein, is a haplo- and triplo-suppressor of position effect variegation.

ABSTRACT: The Drosophila heterochromatin protein 1 (HP1) regulates epigenetic gene silencing and heterochromatin formation by promoting and maintaining chromatin condensation. Here we report the identification and characterization of an HP1-interacting protein (Hip). Hip interacts with HP1 in vitro and is associated with HP1 in vivo. This interaction is mediated by at least three independent but similar HP1-binding modules of the Hip protein. Hip and HP1 completely colocalize in the pericentric heterochromatin, and both haplo- and triplo-dosage mutations act as dominant suppressors of position effect variegation. These findings identify a player in heterochromatinization and suggest that Hip cooperates with HP1 in chromatin remodeling and gene silencing.

SUBMITTER: Schwendemann A

PROVIDER: S-EPMC2224187 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature

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Hip, an HP1-interacting protein, is a haplo- and triplo-suppressor of position effect variegation.

Schwendemann Alexander A Matkovic Tanja T Linke Christian C Klebes Ansgar A Hofmann Annemarie A Korge Günter G

Proceedings of the National Academy of Sciences of the United States of America 20071227 1

The Drosophila heterochromatin protein 1 (HP1) regulates epigenetic gene silencing and heterochromatin formation by promoting and maintaining chromatin condensation. Here we report the identification and characterization of an HP1-interacting protein (Hip). Hip interacts with HP1 in vitro and is associated with HP1 in vivo. This interaction is mediated by at least three independent but similar HP1-binding modules of the Hip protein. Hip and HP1 completely colocalize in the pericentric heterochro ...[more]

PMID: 18162556

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