Role Of Human INO80Chromatin Remodeling Complex In DSB Repair Process

DNA double strand break（DSB）is the most serious type of DNA damage.DSBcan be generatedd by some physical or chemical factors such as camptothecin(CPT),hydroxyurea(HU), ionizing radiation(IR),and fork collapse. hINO80is one of themost significant Chromatin remodeling enzymes.It is involved in many cellprograms,such as regulation of transcription,DNA replication,cell division and DNAdouble strand break repair.In human cells,H2AX was phosphorylated into-H2AXduring DSB repair and recruited to the DSB sites.When the repair is completed,-H2AX can be dephosphorylated back into H2AX.We observed these processes byimmunofluorescence and we were surprised to find that hINO80could colocalizewith-H2AX on DSB sites,especially that one of the subunits,Arp8,was essencial forthe colocalization.After we knockdown the Arp8subunit,hINO80could no longercolocalize with-H2AX on DSB sites.And we demonstrated that the cells whichlacked Arp8were abnormal in DSB repair process by Comet Assay.