Cytomegalovirus immediate-early protein 2 (IE2)

Cytomegalovirus immediate-early protein 2 (IE2) is a major regulatory protein encoded by the UL122 open reading frame of human cytomegalovirus (HCMV)[6]. It is a nuclear phosphoprotein, typically around 80–86 kDa, produced very early following infection, and is essential for activating the transcription of viral early genes and progression from the immediate-early to early phase of infection[1][2][3]. IE2 plays a central role in viral gene expression, cell cycle modulation, and inhibition of apoptotic and immune responses, facilitating viral persistence and replication[1][2][3][6]. Various spliced mRNAs can give rise to IE2 isoforms, but all major forms require exon 5 for functional activity[1]. IE2 is not a conventional human therapeutic target like a receptor or enzyme, though it is essential for the virus and therefore is a target of interest for antiviral research.

Other names

Immediate-early 2 proteinHCMV IE2IE2 protein (UL122 gene product)IE2UL122 gene product

Not directly targeted by approved drugs; mechanisms would involve inhibition of viral gene transcription and replication if direct inhibitors were discovered.