A genome-wide camptothecin sensitivity screen identifies a mammalian MMS22L-NFKBIL2 complex required for genomic stability.
Replication stress involving collision of replisomes with camptothecin (CPT)-stabilized DNA-Topoisomerase I adducts activates an ATR-dependent pathway to promote repair by homologous recombination. To identify human genes that protect cells from such replication stress, we performed a genome-wide CPT sensitivity screen. Among numerous candidate genes are two previously unstudied proteins: the ankyrin repeat protein NFKBIL2 and C6ORF167 (MMS22L), distantly related to yeast replication stress regulator Mms22p. MMS22L and NFKBIL2 interact with each other and with FACT (facilitator of chromatin transcription) and MCM (minichromosome maintenance) complexes. Cells depleted of NFKBIL2 or MMS22L are sensitive to DNA-damaging agents, load phosphorylated RPA onto chromatin in a CTIP-dependent manner, activate the ATR/ATRIP-CHK1 and double-strand break repair signaling pathways, and are defective in HR. This study identifies MMS22L-NFKBIL2 as components of the replication stress control pathway and provides a resource for discovery of additional components of this pathway.
Department of Pathology, Harvard Medical School, Boston, MA 02115, USA.
Brenda C
BC
O'Connell
Britt
B
Adamson
John R
JR
Lydeard
Mathew E
ME
Sowa
Alberto
A
Ciccia
Andrea L
AL
Bredemeyer
Michael
M
Schlabach
Steven P
SP
Gygi
Stephen J
SJ
Elledge
J Wade
JW
Harper
D002166:Camptothecin / Q000494:pharmacology*; D004249:DNA Damage; D004260:DNA Repair / Q000187:drug effects; D004261:DNA Replication / Q000187:drug effects; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D005820:Genetic Testing; D015894:Genome, Human / Q000235:genetics*; D042822:Genomic Instability / Q000187:drug effects*; D006367:HeLa Cells; D006657:Histones / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D009097:Multienzyme Complexes / Q000378:metabolism; D016328:NF-kappa B / Q000172:deficiency / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D034741:RNA, Small Interfering / Q000378:metabolism; D011995:Recombination, Genetic / Q000187:drug effects / Q000235:genetics; D051716:Replication Protein A / Q000378:metabolism; D015203:Reproducibility of Results; D013312:Stress, Physiological / Q000187:drug effects; D000071857:Tumor Suppressor p53-Binding Protein 1; D000099272:Replisomes
D002166:Camptothecin; D004268:DNA-Binding Proteins; D004259:DNA-Directed DNA Polymerase; D006657:Histones; D047908:Intracellular Signaling Peptides and Proteins; D009097:Multienzyme Complexes; D016328:NF-kappa B; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D051716:Replication Protein A; D000071857:Tumor Suppressor p53-Binding Protein 1; D000099272:Replisomes; C468783:H2AX protein, human; C554517:MMS22L protein, human; C093394:TONSL protein, human; C498301:TP53BP1 protein, human; C516794:RPA2 protein, human