PXD057316-1

PXD057316 is an original dataset announced via ProteomeXchange.

Title	Phosphorylation of HP1/Swi6 tunes chromatin a¬ffinity and relieves inhibition on Suv39/Clr4 H3K9 trimethyl spreading.
Description	Heterochromatin formation in Schizosaccharomyces pombe requires the spreading of histone 3 (H3) Lysine 9 (K9) methylation (me) from nucleation centers by the H3K9 methylase, Suv39/Clr4, and the reader protein, HP1/Swi6. To accomplish this, Suv39/Clr4 and HP1/Swi6 have to associate with nucleosomes both nonspecifically, binding DNA and octamer surfaces and specifically, via recognition of methylated H3K9 by their respective chromodomains. However, how both proteins avoid competition for the same nucleosomes in this process is unclear. Here, we show that phosphorylation tunes the nucleosome affinity of HP1/Swi6 such that it preferentially partitions onto Suv39/Clr4’s trimethyl product rather than its unmethylated substrates. Preferential partitioning enables efficient conversion from di-to trimethylation on nucleosomes in vitro and H3K9me3 spreading in vivo. Together, our data suggests that phosphorylation of HP1/Swi6 creates a regime that relieves competition with the “read-write” mechanism of Suv39/Clr4 for productive heterochromatin spreading.
HostingRepository	PRIDE
AnnounceDate	2025-12-22
AnnouncementXML	Submission_2025-12-21_16:33:55.539.xml
DigitalObjectIdentifier	https://dx.doi.org/10.6019/PXD057316
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Supported dataset by repository
PrimarySubmitter	Robert Maxwell
SpeciesList	scientific name: Saccharomyces cerevisiae (Baker's yeast); NCBI TaxID: NEWT:4932;
ModificationList	biotinylated residue; phosphorylated residue; monohydroxylated residue; iodoacetamide derivatized residue
Instrument	Orbitrap Fusion Lumos; LTQ

Revision	Datetime	Status	ChangeLog Entry
0	2024-10-29 14:53:05	ID requested
⏵ 1	2025-12-21 16:33:56	announced

10.1093/nar/gkaf1244;

10.6019/PXD057316;

Kennedy DR, Lemi, è, re J, Amine AAA, Martin EW, Tan C, Simental E, Braxton J, Maxwell RA, Al-Sady B, Phosphorylation of HP1/Swi6 relieves competition with Suv39/Clr4 on nucleosomes and enables H3K9 trimethyl spreading. Nucleic Acids Res, 53(22):(2025) [pubmed]

submitter keyword: LC-MS, Yeast, IP-MS

Bassem Al-Sady
contact affiliation	Associate Professor Department of Microbiology and Immunology The G.W. Hooper Research Foundation The University of California, at San Francisco 513 Parnassus Ave, HSW 1532, Box 0552 San Francisco, CA 94143
contact email	Bassem.Al-sady@ucsf.edu
lab head
Robert Maxwell
contact affiliation	UCB
contact email	robmaxwell@berkeley.edu
dataset submitter

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PRIDE project URI

• PRIDE
  1. PXD057316
     1. Label: PRIDE project
     2. Name: Phosphorylation of HP1/Swi6 tunes chromatin a¬ffinity and relieves inhibition on Suv39/Clr4 H3K9 trimethyl spreading.