Alphaherpesvirus proteins related to herpes simplex virus type 1 ICPO induce the formation of colocalizing, conjugated ubiquitin

Herpes simplex virus type 1 immediate early protein ICP0 influences virus i nfection by inducing the degradation of specific cellular proteins via a me chanism requiring its RING finger and the ubiquitin-proteasome pathway. Man y RING finger proteins, by virtue of their RING finger domain, interact wit h E2 ubiquitin-conjugating enzymes and act as a component of an E3 ubiquiti n ligase. We have recently shown that ICP0 induces the accumulation of colo calizing, conjugated ubiquitin, suggesting that ICP0 can act as or contribu te to an E3 ubiquitin ligase, In this report we demonstrate that the ICP0-r elated RING finger proteins encoded by other alphaherpesviruses also induce colocalizing, conjugated ubiquitin, thereby suggesting that they act by si milar biochemical mechanisms.