FIG. 7.

The product of the UL100 open reading frame, gM, localizes in the ER and ERGIC in transfected cells. Cos-7 cells were grown on glass coverslips and transfected with a plasmid for gM. The coverslips were processed for imaging as described in Materials and Methods. The intracellular location of gM was determined by comparing the signal from the anti-gM antibody IMP 91-3/1 with those of antibodies or lectins specific for markers of the cellular secretory system. The cellular markers and associated antibodies were as follows: ER, anticalreticulin; ERGIC, anti-p115(TAP); Golgi, anti-GM130; and TGN, WGA. The antibodies reactive with the cellular markers were developed with Texas red and anti-gM MAb binding by fluorescein isothiocyanate-conjugated anti-mouse IgG. Yellow indicates colocalization of the signal.