<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <ProteomeXchangeDataset id="PXD045534" formatVersion="1.4.0" xsi:noNamespaceSchemaLocation="proteomeXchange-1.4.0.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <CvList> <Cv fullName="PSI-MS" uri="https://raw.githubusercontent.com/HUPO-PSI/psi-ms-CV/master/psi-ms.obo" id="MS"/> <Cv fullName="PSI-MOD" uri="https://raw.githubusercontent.com/MICommunity/psidev/master/psi/mod/data/PSI-MOD.obo" id="MOD"/> <Cv fullName="UNIMOD" uri="http://www.unimod.org/obo/unimod.obo" id="UNIMOD"/> </CvList> <DatasetSummary announceDate="2024-08-27" hostingRepository="PRIDE" title="Shieldin/CST-dependent and independent functions of 53BP1 control DNA end-joining and repair pathway choice"> <Description>53BP1 regulates DNA end-joining in lymphocytes, diversifying immune antigen receptors. This involves nucleosome-bound 53BP1 at DNA double-stranded breaks (DSBs) recruiting RIF1 and shieldin, a poorly understood DNA-binding complex. The 53BP1-RIF1-shieldin axis is pathological in BRCA1-mutated cancers, blocking homologous recombination (HR) and driving illegitimate non-homologous end-joining (NHEJ). However, how this axis regulates DNA end-joining and HR suppression remains unresolved. We investigated shieldin and its interplay with CST, a complex recently implicated in 53BP1-dependent activities. Immunophenotypically, mice lacking shieldin or CST are equivalent, with class-switch recombination co-reliant on both complexes. DNA damage-responsive signalling promotes shieldin-CST interaction, demonstrating shieldin as a DSB-specific CST adaptor. Furthermore, DNA polymerase ΞΆ functions downstream of shieldin, establishing DNA fill-in synthesis as the physiological function of shieldin-CST. Lastly, 53BP1 suppresses HR and promotes NHEJ in BRCA1-deficient cells independently of shieldin. These findings showcase the resilience of the 53BP1 pathway, achieved through the collaboration of chromatin-bound 53BP1 complexes and DNA end-processing effector proteins.</Description> <ReviewLevel> <cvParam cvRef="MS" accession="MS:1002854" name="Peer-reviewed dataset"/> </ReviewLevel> <RepositorySupport> <cvParam cvRef="MS" accession="MS:1002856" name="Supported dataset by repository"/> </RepositorySupport> </DatasetSummary> <DatasetIdentifierList> <DatasetIdentifier> <cvParam cvRef="MS" accession="MS:1001919" name="ProteomeXchange accession number" value="PXD045534"/> </DatasetIdentifier> <DatasetIdentifier> <cvParam cvRef="MS" accession="MS:1001922" name="Digital Object Identifier (DOI)" value="10.6019/PXD045534"/> </DatasetIdentifier> </DatasetIdentifierList> <DatasetOriginList> <DatasetOrigin> <cvParam cvRef="MS" accession="MS:1002868" name="Original data"/> </DatasetOrigin> </DatasetOriginList> <SpeciesList> <Species> <cvParam cvRef="MS" accession="MS:1001469" name="taxonomy: scientific name" value="Mus musculus (Mouse)"/> <cvParam cvRef="MS" accession="MS:1001467" name="taxonomy: NCBI TaxID" value="10090"/> </Species> </SpeciesList> <InstrumentList> <Instrument id="Instrument_1"> <cvParam cvRef="MS" accession="MS:1002523" name="Q Exactive HF"/> </Instrument> </InstrumentList> <ModificationList> <cvParam cvRef="MOD" accession="MOD:00696" name="phosphorylated residue"/> <cvParam cvRef="MOD" accession="MOD:00394" name="acetylated residue"/> <cvParam cvRef="MOD" accession="MOD:00400" name="deamidated residue"/> <cvParam cvRef="MOD" accession="MOD:00397" name="iodoacetamide derivatized residue"/> </ModificationList> <ContactList> <Contact id="project_submitter"> <cvParam cvRef="MS" accession="MS:1000586" name="contact name" value="Robert Parker"/> <cvParam cvRef="MS" accession="MS:1000589" name="contact email" value="robert.rparker@gmail.com"/> <cvParam cvRef="MS" accession="MS:1000590" name="contact affiliation" value="Jenner Institute"/> <cvParam cvRef="MS" accession="MS:1002037" name="dataset submitter"/> </Contact> <Contact id="project_lab_head"> <cvParam cvRef="MS" accession="MS:1002332" name="lab head"/> <cvParam cvRef="MS" accession="MS:1000586" name="contact name" value="J. Ross Chapman"/> <cvParam cvRef="MS" accession="MS:1000589" name="contact email" value="ross.chapman@imm.ox.ac.uk"/> <cvParam cvRef="MS" accession="MS:1000590" name="contact affiliation" value="Genome Integrity laboratory, Medical Research Council Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, The University of Oxford, Oxford, UK"/> </Contact> </ContactList> <PublicationList> <Publication id="DOI-10_1038_S41594_024_01381_9"> <cvParam cvRef="MS" accession="MS:1001922" name="Digital Object Identifier (DOI)" value="10.1038/S41594-024-01381-9"/> </Publication> <Publication id="DOI-10_6019_PXD045534"> <cvParam cvRef="MS" accession="MS:1001922" name="Digital Object Identifier (DOI)" value="10.6019/PXD045534"/> </Publication> </PublicationList> <KeywordList> <cvParam cvRef="MS" accession="MS:1001925" name="submitter keyword" value="CST, Shieldin, DNA damage response"/> </KeywordList> <FullDatasetLinkList> <FullDatasetLink> <cvParam cvRef="MS" accession="MS:1002852" name="Dataset FTP location" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534"/> </FullDatasetLink> <FullDatasetLink> <cvParam cvRef="MS" accession="MS:1001930" name="PRIDE project URI" value="http://www.ebi.ac.uk/pride/archive/projects/PXD045534"/> </FullDatasetLink> </FullDatasetLinkList> <DatasetFileList> <DatasetFile id="FILE_1" name="peptides_1_1_0.mzid.gz"> <cvParam cvRef="MS" accession="MS:1002848" name="Result file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/peptides_1_1_0.mzid.gz"/> </DatasetFile> <DatasetFile id="FILE_2" name="HFX0062_IPP183_C1_GST_1.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HFX0062_IPP183_C1_GST_1.raw"/> </DatasetFile> <DatasetFile id="FILE_3" name="HXF0062_IPP183_H3_SHLD3_1.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_H3_SHLD3_1.raw"/> </DatasetFile> <DatasetFile id="FILE_4" name="Ash2_SHLD.mgf"> <cvParam cvRef="MS" accession="MS:1002850" name="Peak list file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/Ash2_SHLD.mgf"/> </DatasetFile> <DatasetFile id="FILE_5" name="HXF0062_IPP183_C1_SHLD1_IR_1.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_C1_SHLD1_IR_1.raw"/> </DatasetFile> <DatasetFile id="FILE_6" name="HXF0062_IPP183_C1_SHLD1_2.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_C1_SHLD1_2.raw"/> </DatasetFile> <DatasetFile id="FILE_7" name="HXF0062_IPP183_H3_SHLD3_IR_2.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_H3_SHLD3_IR_2.raw"/> </DatasetFile> <DatasetFile id="FILE_8" name="HXF0062_IPP183_H3_SHLD3_IR_1.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_H3_SHLD3_IR_1.raw"/> </DatasetFile> <DatasetFile id="FILE_9" name="HXF0062_IPP183_C1_SHLD1_IR_2.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_C1_SHLD1_IR_2.raw"/> </DatasetFile> <DatasetFile id="FILE_10" name="HXF0062_IPP183_C1_SHLD1_1.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_C1_SHLD1_1.raw"/> </DatasetFile> <DatasetFile id="FILE_11" name="HXF0062_IPP183_H3_SHLD3_2.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HXF0062_IPP183_H3_SHLD3_2.raw"/> </DatasetFile> <DatasetFile id="FILE_12" name="checksum.txt"> <cvParam cvRef="MS" accession="MS:1002851" name="Other type file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/checksum.txt"/> </DatasetFile> <DatasetFile id="FILE_13" name="HFX0062_IPP183_C1_GST_2.raw"> <cvParam cvRef="MS" accession="MS:1002846" name="Associated raw file URI" value="ftp://ftp.pride.ebi.ac.uk/pride/data/archive/2024/08/PXD045534/HFX0062_IPP183_C1_GST_2.raw"/> </DatasetFile> </DatasetFileList> <RepositoryRecordList> <RepositoryRecord name="Shieldin/CST-dependent and independent functions of 53BP1 control DNA end-joining and repair pathway choice" label="PRIDE project" recordID="PXD045534" repositoryID="PRIDE" uri="http://www.ebi.ac.uk/pride/archive/projects/PXD045534"/> </RepositoryRecordList> </ProteomeXchangeDataset>