EXPRESSION OF HIV-1 NEF IN YEAST CAUSES MEMBRANE PERTURBATION AND RELEASE OF THE MYRISTYLATED NEF PROTEIN

The human immunodeficiency virus type 1 (HIV-1) Nef protein is essenti al for AIDS pathogenesis, but its function remains highly controversia l. During stresses such as growth in the presence of copper or at elev ated temperature, myristylated Nef is released from yeast cells and, a fter extended culture in stationary phase, it accumulates in the super natant as a dense membranous material that can be centrifuged into a d iscrete layer above the cell pellet. This material is unique to Nef-pr oducing cells and represents a convenient source of Nef that may have application in further biological studies. Within the yeast cell, elec tron microscopic examination shows that Nef localises in novel, membra ne-bound bodies. These data support the evidence for a role of Nef in membrane perturbation and suggest that there may be a similar localisa tion for myristylated Nef in HIV-I infected cells.