Histone variants play crucial roles in gene expression, genome integrity, and chromosome segregation. We report that the four H2A variants in Arabidopsis define different genomic features, contributing to overall genomic organization. The histone variant H2A.W marks heterochromatin specifically and acts in synergy with heterochromatic marks H3K9me2 and DNA methylation to maintain transposon silencing. In vitro, H2A.W enhances chromatin condensation by promoting fiber-to-fiber interactions via its conserved C-terminal motif. In vivo, H2A.W is required for heterochromatin condensation, demonstrating that H2A.W plays critical roles in heterochromatin organization. Similarities in conserved motifs between H2A.W and another H2A variant in metazoans suggest that plants and animals share common mechanisms for heterochromatin condensation.
|Number of pages||12|
|State||Published - Jul 3 2014|
Bibliographical noteFunding Information:
R.Y., S.H., X.N., and F.B. were funded by Temasek Life Sciences Laboratory. Sequencing was performed at the UCLA BSCRC BioSequencing Core facility. We thank Meredith Calvert for help with imaging and Mahnaz Akhavan for Illumina sequencing. We thank Dr. Maruyama for his comments and support with the graphical abstract. H.S. was supported by a Dissertation Year Fellowship from UCLA. X.Z. is a research fellow of Ruth L. Kirschstein National Research Service Award (F32GM096483-01). S.F. is a Special Fellow of the Leukemia & Lymphoma Society. Work in the Jacobsen lab was supported by NSF grant 1121245. K.L., U.M., and K.Z. are supported by NIH-GM067777. M.G. is supported by EMBO ALTF 986-2011 and HHMI. S.E.J. and K.L. are Investigators of the Howard Hughes Medical Institute.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology (all)