KSHV (Kaposi's sarcoma-associated herpesvirus) belongs to the gamma-2 herpesvirus subfamily and has been closely linked to the Kaposi’s sarcoma, primary effusion lymphoma (PEL) and multicentric Castleman’s disease. The genome of KSHV is 165-170 kb and contains at least 88 open reading frames. ORF45 protein encoded by an immediate-early gene in the KSHV genome is characterized as a phosphorylated protein and it is localized in the cytoplasm of infected cells. Studies have shown that ORF45 Protein interacted with cellular IRF-7 and blocked virus-mediated phosphorylation and nuclear translocation of IRF-7. In consequence, ORF45 efficiently inhibited virus-induced production of type I IFN. It was reported that the ORF45 protein was associated with purified virions.