Epstein-Barr virus latent membrane protein: induction of B-cell activation antigens and membrane patch formation does not require vimentin.

The latent membrane protein (LMP) of Epstein-Barr virus (EBV) forms patches associated with the vimentin intermediate filament system in EBV-transformed lymphoblastoid cell lines, EBV-infected Burkitt's lymphoma cells, and LMP-transfected, EBV-negative Burkitt's lymphoma cells. By gene transfer, LMP induces the expression of vimentin and B-cell activation antigens in EBV-negative Burkitt's lymphoma cells. We have now expressed LMP in an EBV-positive Burkitt's lymphoma cell line, Daudi, which does not express any LMP or vimentin. In these Daudi transfectants, LMP still formed plasma membrane patches in the absence of vimentin. LMP did not resist nonionic detergent extraction in Daudi cells as it does in vimentin-expressing cells. LMP still retained functional activity as judged by induction of B-cell activation antigens. These data indicate that LMP can form plasma membrane patches and induce B-lymphocyte activation independent of vimentin association.