PXD053321

PXD053321 is an original dataset announced via ProteomeXchange.

Title	O-GlcNAcylation of RPA2 at S4/S8 antagonizes phosphorylation and regulates checkpoint activation during replication stress
Description	O-linked N-acetylglucosamine (O-GlcNAc) is the only mono-saccharide modification occurring in the cytoplasm, nucleus and mitochondria. Recent advent of the mass spectrometry technology has enabled identification of abundant O-GlcNAc transferase (OGT) substrates in diverse biological processes, such as cell cycle progression, replication and DNA damage response. Herein we report the O-GlcNAcylation of Replication Protein A2 (RPA2), a component of the heterotrimeric RPA complex pivotal for DNA metabolism. We found that RPA2 interacts with OGT, and a topoisomerase II inhibitor, Etoposide, diminishes the association. Using stepped collision energy higher-energy collisional dissociation mass spectrometry, we mapped RPA2 O-GlcNAc sites to be Ser-4/Ser-8, which are well-known PIKK-dependent RPA2 phosphorylation sites involved in checkpoint activation upon replication stress. We further demonstrated that Ser-4/Ser-8 O-GlcNAcylation antagonizes phosphorylation and impairs downstream Chk1 activation. Moreover, RPA2 O-GlcNAcylation sustains H2AX phosphorylation upon Etoposide treatment, and promotes inappropriate cell cycle progression, indicative of checkpoint defects. Our work not only unveils a new OGT substrate, but also underscores the distinct roles of OGT in replication versus replication stress
HostingRepository	iProX
AnnounceDate	2024-06-21
AnnouncementXML	Submission_2024-12-12_19:08:22.336.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Guangcan Shao
SpeciesList	scientific name: Homo sapiens; NCBI TaxID: 9606;
ModificationList	No PTMs are included in the dataset
Instrument	Q Exactive HF

Revision	Datetime	Status	ChangeLog Entry
0	2024-06-23 19:57:08	ID requested
⏵ 1	2024-12-12 19:08:23	announced

Zhao J, Shao G, Lu X, Lv Z, Dong MQ, Liu X, Li J, O-GlcNAcylation of RPA2 at S4/S8 antagonizes phosphorylation and regulates checkpoint activation during replication stress. J Biol Chem, 300(12):107956(2024) [pubmed]

submitter keyword: O-GlcNAcylation, RPA2

Jing Li
contact affiliation	Capital Normal University
contact email	jing_li@mail.cnu.edu.cn
lab head
Guangcan Shao
contact affiliation	Capital Normal University
contact email	shaoguangcan@nibs.ac.cn
dataset submitter

iProX dataset URI