Physical and functional interaction between heterochromatin protein 1alpha and the RNA-binding protein heterogeneous nuclear ribonucleoprotein U.

Fiche publication


Date publication

octobre 2009

Auteurs

Membres identifiés du Cancéropôle Est :
Dr HAMICHE Ali


Tous les auteurs :
Ameyar-Zazoua M, Souidi M, Fritsch L, Robin P, Thomas A, Hamiche A, Percipalle P, Ait-Si-Ali S, Harel-Bellan A

Résumé

By combining biochemical purification and mass spectrometry, we identified proteins associated with human heterochromatin protein 1alpha (HP1alpha) both in the nucleoplasm and in chromatin. Some of these are RNA-binding proteins, and among them is the protein heterogeneous nuclear ribonucleoprotein U (hnRNP U)/SAF-A, which is linked to chromatin organization and transcriptional regulation. Here, we demonstrate that hnRNP U is a bona fide HP1alpha-interacting molecule. More importantly, hnRNP U depletion reduces HP1alpha-dependent gene silencing and disturbs HP1alpha subcellular localization. Thus, our data demonstrate that hnRNP U is involved in HP1alpha function, shedding new light on the mode of action of HP1alpha and on the function of hnRNP U.

Référence

J Biol Chem. 2009 Oct 9;284(41):27974-9