Plays an essential role in egress of virus particles from the nucleus, cytoplasmic envelopment and virus-induced cell fusion. Forms a functional protein complex with gK and this interaction is absolutely essential for their coordinate intracellular transport, gK glycosylation, expression on host cell surface, and function. Together, they modulate gB-mediated virus-induced cell fusion and virion egress and therefore actively participate in these processes. In addition, plays a role in inhibiting the type I interferon responses by suppressing STING1-mediated activation of the IFN-beta promoter