The endoplasmic reticulum-resident stress protein gp96 binds peptides translocated by TAP

The endoplasmic reticulum (ER)-resident stress protein gp96 induces a major histocompatibility complex class I-restricted cytotoxic T lymphocyte (CTL) response against antigens present in the cells from which it has been prepared. In this study, photoreactive peptides were translocated into the ER by the transporter associated with antigen processing (TAP). These peptides can be cross-linked specifically to gp96. Thus, we provide the first evidence that gp96 binds TAP-translocated peptides which have been implicated in the induction of specific CTL responses after immunization with gp96 (Srivastava, P. K. et al., Immunogenetics 1994. 39: 93).