RRC ID 57325
Author Unoki M, Funabiki H, Velasco G, Francastel C, Sasaki H.
Title CDCA7 and HELLS mutations undermine nonhomologous end joining in centromeric instability syndrome.
Journal J Clin Invest
Abstract Mutations in CDCA7 and HELLS that respectively encode a CXXC-type zinc finger protein and an SNF2 family chromatin remodeler cause immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome types 3 and 4. Here, we demonstrate that the classical nonhomologous end joining (C-NHEJ) proteins Ku80 and Ku70, as well as HELLS, coimmunoprecipitated with CDCA7. The coimmunoprecipitation of the repair proteins was sensitive to nuclease treatment and an ICF3 mutation in CDCA7 that impairs its chromatin binding. The functional importance of these interactions was strongly suggested by the compromised C-NHEJ activity and significant delay in Ku80 accumulation at DNA damage sites in CDCA7- and HELLS-deficient HEK293 cells. Consistent with the repair defect, these cells displayed increased apoptosis, abnormal chromosome segregation, aneuploidy, centrosome amplification, and significant accumulation of γH2AX signals. Although less prominent, cells with mutations in the other ICF genes DNMT3B and ZBTB24 (responsible for ICF types 1 and 2, respectively) showed similar defects. Importantly, lymphoblastoid cells from ICF patients shared the same changes detected in the mutant HEK293 cells to varying degrees. Although the C-NHEJ defect alone did not cause CG hypomethylation, CDCA7 and HELLS are involved in maintaining CG methylation at centromeric and pericentromeric repeats. The defect in C-NHEJ may account for some common features of ICF cells, including centromeric instability, abnormal chromosome segregation, and apoptosis.
Volume 129(1)
Pages 78-92
Published 2019-1-2
DOI 10.1172/JCI99751
PII 99751
PMID 30307408
PMC PMC6307953
MeSH Apoptosis / genetics Centromere / genetics Centromere / metabolism Centromere / pathology Chromosome Segregation / genetics CpG Islands DNA Damage DNA End-Joining Repair* DNA Helicases / genetics DNA Helicases / metabolism* DNA Methylation* Face / abnormalities* Face / pathology Female HEK293 Cells Humans Immunologic Deficiency Syndromes / genetics Immunologic Deficiency Syndromes / metabolism* Immunologic Deficiency Syndromes / pathology Ku Autoantigen / genetics Ku Autoantigen / metabolism Male Mutation* Nuclear Proteins / genetics Nuclear Proteins / metabolism* Primary Immunodeficiency Diseases
IF 12.282
Times Cited 12
DNA material p3XFLAG-CDCA7 WT (RDB17374) p3XFLAG-CDCA7 R274C (RDB17375) p3XFLAG-HELLS WT (RDB17376) p3XFLAG-HELLS Q699R (RDB17377) DNMT3B px330 (RDB17378) ZBTB24 px330 (RDB17379) CDCA7 px330 (RDB17380) HELLS px330 (RDB17381) Ku80 px330 (RDB17382)
Human and Animal Cells HEV0190