EXPRESSION OF HIV-1 ENVELOPE GLYCOPROTEIN ALTERS CELLULAR CALMODULIN

Removal of parts of a known calmodulin binding site at the C-terminus of HIV-1 envelope glycoprotein, gp 160, can result in diminished infec tivity. We investigated whether expression of full length gp 160 would result in changes in intracellular calmodulin compared to expression of gp160 truncated to remove both known calmodulin binding sites. Both Western and Northern blots demonstrated that expression of gp160 led to increased calmodulin when compared to expression of truncated gp160 . The induced calmodulin was associated preferentially with a particul ate subcellular fraction. Confocal immunomicroscopy confirmed the incr ease in calmodulin and also showed that there was enhanced colocalizat ion of calmodulin with gp160. Understanding of the role of calmodulin in the viral life-cycle may lead to new therapeutics. (C) 1996 Academi c Press, Inc.