Histone H2A C-Terminus Regulates Chromatin Dynamics, Remodeling, and Histone H1 Binding

Christine Vogler,Andres Joaquin Lopez-Contreras,Tanja Waldmann,Lora Braun,Sylvain Daujat,Isabelle Chassignet,Annalisa Izzo,Ramona Ettig,Miroslav Dundr,Robert Schneider,Claudia Huber,Oscar Fernandez-Capetillo,Gernot Längst,Karsten Rippe

doi:10.1371/journal.pgen.1001234

Abstract

The tails of histone proteins are central players for all chromatin-mediated processes. Whereas the N-terminal histone tails have been studied extensively, little is known about the function of the H2A C-terminus. Here, we show that the H2A C-terminal tail plays a pivotal role in regulating chromatin structure and dynamics. We find that cells expressing C-terminally truncated H2A show increased stress sensitivity. Moreover, both the complete and the partial deletion of the tail result in increased histone exchange kinetics and nucleosome mobility in vivo and in vitro. Importantly, our experiments reveal that the H2A C-terminus is required for efficient nucleosome translocation by ISWI-type chromatin remodelers and acts as a novel recognition module for linker histone H1. Thus, we suggest that the H2A C-terminal tail has a bipartite function: stabilisation of the nucleosomal core particle, as well as mediation of the protein interactions that control chromatin dynamics and conformation.

Highlights

In the eukaryotic nucleus, DNA is stored in a nucleoprotein complex referred to as chromatin
We show here that it can interact with the linker histone H1 that is important for higher order chromatin structure
We find that this tail is involved in regulating nucleosome dynamics and mobility of H2A itself

Summary

Introduction

DNA is stored in a nucleoprotein complex referred to as chromatin. This packaging of DNA does serve to condense DNA into a highly compacted form, it is fundamental for the regulation of all DNA-dependent processes such as transcription, replication and DNA repair [1]. Accessibility to DNA sequences occluded by nucleosomes can be regulated by chromatin remodeling complexes. These enzymes use energy from ATP hydrolysis to disrupt contacts between the histone octamer and the DNA and move nucleosomes along the DNA. By modulating chromatin fluidity they are necessary for transcription, but for all DNAdependent processes such as replication, recombination and DNA repair [5,6]

Methods

Results

Discussion

Conclusion