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Multiscale analysis of dynamics and interactions of heterochromatin protein 1 by fluorescence fluctuation microscopy.

ABSTRACT: Heterochromatin protein 1 (HP1) is a central factor in establishing and maintaining the repressive heterochromatin state. To elucidate its mobility and interactions, we conducted a comprehensive analysis on different time and length scales by fluorescence fluctuation microscopy in mouse cell lines. The local mobility of HP1alpha and HP1beta was investigated in densely packed pericentric heterochromatin foci and compared with other bona fide euchromatin regions of the nucleus by fluorescence bleaching and correlation methods. A quantitative description of HP1alpha/beta in terms of its concentration, diffusion coefficient, kinetic binding, and dissociation rate constants was derived. Three distinct classes of chromatin-binding sites with average residence times t(res)

SUBMITTER: Muller KP

PROVIDER: S-EPMC2784559 | biostudies-other | 2009 Dec

REPOSITORIES: biostudies-other

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Multiscale analysis of dynamics and interactions of heterochromatin protein 1 by fluorescence fluctuation microscopy.

Müller Katharina P KP Erdel Fabian F Caudron-Herger Maïwen M Marth Caroline C Fodor Barna D BD Richter Mario M Scaranaro Manuela M Beaudouin Joël J Wachsmuth Malte M Rippe Karsten K

Biophysical journal 20091201 11

Heterochromatin protein 1 (HP1) is a central factor in establishing and maintaining the repressive heterochromatin state. To elucidate its mobility and interactions, we conducted a comprehensive analysis on different time and length scales by fluorescence fluctuation microscopy in mouse cell lines. The local mobility of HP1alpha and HP1beta was investigated in densely packed pericentric heterochromatin foci and compared with other bona fide euchromatin regions of the nucleus by fluorescence blea ...[more]

PMID: 19948116

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