Research progress in function of human cytomegalovirus IE protein

Human cytomegalovirus (HCMV) infection is widespread. According to different economic conditions, the serology positive rate among people ranges from 40% to 100%. HCMV belongs to the β-herpesvirus subfamily, the virus contains an amazing enormous genome of approximately 250 kb that encodes over 200 and perhaps as many as 751 protein products. Notably, IE1 encoded by UL123 and IE2 encoded by UL122 are the most abundant and important among them.IE1 is a powerful transcription activator, which is also the first expressed protein after HCMV infection. Contrast to high MOI, IE1 is essential to virus replication when HCMV is in a low input.IE2 is important for inducing cytolysis effects, which also has an irreplaceable role for viral replication.IE proteins have involved in many mechanisms to resist the innate and adaptive immune responses to cytomegalovirus infection. What’s more, IE proteins are believed to have a role in regulating virus latency and reactivation state. Key words: Human cytomegalovirus; IE proteins; Interferon; Replication; Latency