Effects of calcium ions on proteolytic processing of HIV-1 gp160 precursor and on cell fusion.
Complete activation of human immunodeficiency virus type 1 (HIV-1) requires the endoproteolytic cleavage by cellular protease of the envelope glycoprotein precursor (gp160) into the external glycoprotein gp120, and the transmembrane glycoprotein gp41. We report here the effect of depletion of cellular calcium ions on maturation of precursor gp160 and its concomitant effect on syncytium formation. We show that the cellular endoprotease activity responsible for gp160 maturation and the capacity for HIV-1 to induce syncytium formation are calcium-dependent. In addition, we show that endoproteolytic maturation is a key step in syncytium formation induced by HIV-1.
Moulard
M
M
Laboratorie de Biochimie, CNRS URA 1455-Ingénierie des Protéines, Faculté de Médecine Secteur Nord, Marseille, France.
Montagnier
L
L
Bahraoui
E
E
D000595:Amino Acid Sequence; D002118:Calcium / Q000494:pharmacology*; D002459:Cell Fusion; D002460:Cell Line; D015686:Gene Products, env / Q000378:metabolism*; D015726:Giant Cells; D019302:HIV Envelope Protein gp160; D015497:HIV-1 / Q000378:metabolism*; D008969:Molecular Sequence Data; D011498:Protein Precursors / Q000378:metabolism*; D011499:Protein Processing, Post-Translational
D015686:Gene Products, env; D019302:HIV Envelope Protein gp160; D011498:Protein Precursors; D002118:Calcium