The annealing helicase HARP protects stalled replication forks.
Mutations in HepA-related protein (HARP) are the only identified causes of Schimke immunoosseous dysplasia (SIOD). HARP has a unique annealing helicase activity in vitro, but the in vivo functional significance remains unknown. Here, we demonstrated that HARP is recruited to stalled replication forks via its direct interaction with Replication protein A (RPA). Cells with HARP depletion displayed increased spontaneous DNA damage and G2/M arrest, suggesting that HARP normally acts to stabilize stalled replication forks. Our data place the annealing helicase activity of HARP at replication forks and propose that SIOD syndrome may be caused by the destabilization of replication forks during cell proliferation.
Yuan
Jingsong
J
Department of Experimental Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA.
Ghosal
Gargi
G
Chen
Junjie
J
D000595:Amino Acid Sequence; D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D002460:Cell Line; D045744:Cell Line, Tumor; D004249:DNA Damage; D004265:DNA Helicases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004261:DNA Replication; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D016415:Sequence Alignment
C412482:SMARCAL1 protein, human; D004265:DNA Helicases