N-terminal phosphorylation of HP1α increases its nucleosome-binding specificity.

Nishibuchi, G.; Machida, S.; Osakabe, A.; Murakoshi, H.; Hiragami-Hamada, K.; Nakagawa, R.; Fischle, W.; Nishimura, Y.; Kurumizaka, H.; Tagami, H.; Nakayama, J.

doi:10.1093/nar/gku995

Item

ITEM ACTIONSEXPORT

Add to Basket

Local TagsRelease HistoryDetailsSummary

Released

Journal Article

N-terminal phosphorylation of HP1α increases its nucleosome-binding specificity.

MPS-Authors

/persons/resource/persons132161

Hiragami-Hamada, K.
Research Group of Chromatin Biochemistry, MPI for Biophysical Chemistry, Max Planck Society;

/persons/resource/persons15074

Fischle, W.
Research Group of Chromatin Biochemistry, MPI for Biophysical Chemistry, Max Planck Society;

External Resource

http://nar.oxfordjournals.org/content/42/20/12498.full.pdf+html
(Publisher version)

Fulltext (restricted access)

There are currently no full texts shared for your IP range.

Fulltext (public)

2104853.pdf
(Publisher version), 3MB

Supplementary Material (public)

2104853_Suppl.doc
(Supplementary material), 4MB

Citation

Nishibuchi, G., Machida, S., Osakabe, A., Murakoshi, H., Hiragami-Hamada, K., Nakagawa, R., et al. (2014). N-terminal phosphorylation of HP1α increases its nucleosome-binding specificity. Nucleic Acids Research, 42(20), 12498-12511. doi:10.1093/nar/gku995.

Cite as: https://hdl.handle.net/11858/00-001M-0000-0025-024D-A

Abstract

Heterochromatin protein 1 (HP1) is an evolutionarily conserved chromosomal protein that binds to lysine 9-methylated histone H3 (H3K9me), a hallmark of heterochromatin. Although HP1 phosphorylation has been described in several organisms, the biological implications of this modification remain largely elusive. Here we show that HP1's phosphorylation has a critical effect on its nucleosome binding properties. By in vitro phosphorylation assays and conventional chromatography, we demonstrated that casein kinase II (CK2) is the kinase primarily responsible for phosphorylating the N-terminus of human HP1α. Pull-down assays using in vitro-reconstituted nucleosomes showed that unmodified HP1α bound H3K9-methylated and H3K9-unmethylated nucleosomes with comparable affinity, whereas CK2-phosphorylated HP1α showed a high specificity for H3K9me3-modified nucleosomes. Electrophoretic mobility shift assays showed that CK2-mediated phosphorylation diminished HP1α's intrinsic DNA binding, which contributed to its H3K9me-independent nucleosome binding. CK2-mediated phosphorylation had a similar effect on the nucleosome-binding specificity of fly HP1a and S. pombe Swi6. These results suggested that HP1 phosphorylation has an evolutionarily conserved role in HP1's recognition of H3K9me-marked nucleosomes.