A membrane protein encoded by Epstein-Barr virus in latent growth-transforming infection

The nucleotide sequence of an Epstein-Barr virus gene expressed in latently infected growth-transformed cells is known to include a long open reading frame containing a 33-base-pair repeat element. A bacterial fusion protein constructed from a portion of the reading frame and Escherichia coli β-galactosidase was used to produce sera in rabbits against the previously unidentified gene product. The viral protein detected with these sera in latently infected cells varies in size with the number of copies of the DNA repeat element. Translation of the RNA in vitro yields a protein of similar size. As expected from its primary sequence, the protein is a membrane protein. Immunofluorescence studies with the rabbit antisera suggest that the protein is in the plasma membrane. Thus, this protein could be the lymphocyte-determined membrane antigen (LYDMA) responsible for the generation of T-cell immunity to latently infected cells.