Bombyx mori RPL12 Participates in UV-Induced DNA Damage Repair and Interacts with BmNPV Bm65 Protein Only After Ultraviolet Radiation.

Abstract

Solar ultraviolet radiation (UV) may cause DNA damage. We first report in this study that the large subunit ribosome protein RPL12, from Bomby mori (BmRPL12), participated in UV-induced DNA damage repair. BmRPL12 enhanced the resistance of Escherichia coli (E. coli) to UV radiation and facilitated faster repair of UV-induced DNA damage in silkworm cells. BmRPL12 mainly existed in the cytoplasm in the dimer forms, and the N-terminal nuclear export signal was crucial for the localization of BmRPL12. After UV radiation, BmRPL12 was unable to localize at the UV-induced DNA damage sites to participate in damage repair directly and might indirectly regulate UV-induced DNA damage repair. Our previous research found that BmNPV Bm65 was an important UV damage-induced endonuclease. Here, it was further found that in BmNPV-infected silkworm cells, BmRPL12 in monomeric forms interacted with the virus Bm65 protein only after UV radiation, and BmRPL12 specifically localized at the UV-induced DNA damage sites only in the presence of Bm65. We speculate that after viral infection in cells subjected to UV-induced DNA damage, viral protein Bm65 interacts with BmRPL12 and localizes BmRPL12 to sites of UV-damaged DNA.