Dataset Information

Protein UFMylation regulates ribosomal DNA double-stranded break repair

ABSTRACT: Ribosomal DNA (rDNA) arrays are highly repetitive regions of the genome which encode essential genes required to produce ribosomes. DNA double-stranded breaks (DSBs) generated within rDNA genes elicit a unique cellular response involving robust transcriptional silencing and nucleolar reorganization into ‘cap’ structures at the nucleolar periphery. This process is coordinated by the nucleolar scaffolding protein TCOF1, which functions to recruit the DNA repair proteins NBS1 and TOPBP1 that activate the ATM and ATR kinases, resulting in ribosomal RNA (rRNA) transcriptional silencing and nucleolar segregation. However, the DNA damage and repair response at rDNA arrays remains incompletely understood. Here, we investigate the cellular response to rDNA DSBs using proteomics and genetic CRISPR-Cas9 screening. We show that the protein UFMylation pathway and the HUSH complex are important for cell viability and survival in response to rDNA DSBs, and that the E3 UFM1-ligase UFL1 and its heterodimer DDRGK1 are associated with TCOF1 at nucleolar caps. Loss of UFL1 leads to impaired ATM activation, reduced rRNA transcriptional silencing, and an overall reduction in nucleolar segregation. We identified ATM, UNC45A and SMC6 as UFMylated proteins, in which UFMylation may facilitate ATM activation and segregation of damaged rDNA to the nucleolar periphery. Altogether, our findings provide the first evidence for a role for UFMylation in rDNA DSB repair.

INSTRUMENT(S): Orbitrap Fusion

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Epithelial Cell

SUBMITTER: Marlene Oeffinger

LAB HEAD: Marlene Oeffinger

PROVIDER: PXD048568 | Pride | 2024-09-16

REPOSITORIES: Pride

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			Action	DRS
	OF_20220207_OEF_01.mzid.gz	Mzid
	OF_20220207_OEF_01.mzid_OF_20220207_OEF_01.MGF	Mzid
	OF_20220207_OEF_01.raw	Raw
	OF_20220207_OEF_02.mzid.gz	Mzid
	OF_20220207_OEF_02.mzid_OF_20220207_OEF_02.MGF	Mzid

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Publications

Protein UFMylation regulates early events during ribosomal DNA-damage response.

Panichnantakul Pudchalaluck P Aguilar Lisbeth C LC Daynard Evan E Guest Mackenzie M Peters Colten C Vogel Jackie J Oeffinger Marlene M

Cell reports 20240914 9

The highly repetitive and transcriptionally active ribosomal DNA (rDNA) genes are exceedingly susceptible to genotoxic stress. Induction of DNA double-strand breaks (DSBs) in rDNA repeats is associated with ataxia-telangiectasia-mutated (ATM)-dependent rDNA silencing and nucleolar reorganization where rDNA is segregated into nucleolar caps. However, the regulatory events underlying this response remain elusive. Here, we identify protein UFMylation as essential for rDNA-damage response in human c ...[more]

PMID: 39277864

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