An integral membrane protein (LMP2) blocks reactivation of Epstein-Barr virus from latency following surface immunoglobulin crosslinking.
Abstract
The role of latent membrane protein 2 (LMP2) in Epstein-Barr virus (EBV) infection was evaluated by using latently infected primary B lymphocytes that had been growth transformed by wild-type or specifically mutated EBV recombinants. LMP2 null mutant recombinant EBV-infected cells were similar to normal B lymphocytes in their rapid increase in intracellular free calcium after surface immunoglobulin crosslinking. These cells also became more permissive for lytic EBV replication. In sharp contrast, wild-type control infected cells had little or no increase in intracellular free calcium or in permissivity for EBV replication. The block to surface immunoglobulin crosslinking-induced permissivity in cells expressing wild-type LMP2 could be bypassed by raising intracellular free calcium levels with an ionophore and by activating protein kinase C with phorbol 12-myristate 13-acetate. LMP2A, not LMP2B, mediates this effect on calcium mobilization. Genetic and biochemical data are consistent with these effects being due to the interaction of the LMP2A N-terminal cytoplasmic domain with B lymphocyte src family tyrosine kinases.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- January 1994
- DOI:
- 10.1073/pnas.91.2.772
- Bibcode:
- 1994PNAS...91..772M