CHAPERONE FUNCTIONS COMMON TO NONHOMOLOGOUS EPSTEIN-BARR-VIRUS GL ANDVARICELLA-ZOSTER VIRUS GL PROTEINS

Herpesviruses encode the complex-forming, essential glycoproteins gH a nd gL. Maturation and transport of gH are dependent on coexpression of its chaperone, gL. The gL proteins of alpha herpesviruses and gamma h erpesviruses do not have a significant percentage of amino acid sequen ce homology. Yet, as we report herein, the diverse gL glycoproteins of Epstein-Barr virus (EBV) and varicella-zoster virus (VZV) were functi onally interchangeable, although membrane expression and maturation of gH were separate functions for these viruses. In VZV both functions w ere performed by a single protein, EBV required two separate glycoprot eins, one of which can be replaced by its homologous protein from VZV, a distant relative of EBV. Collectively, these results suggested that VZV gL is a simpler form of the gL chaperone protein than EBV gL.