Furin is important but not essential for the proteolytic maturation of gp160 of HIV-1.
The envelope glycoproteins of HIV are required for viral infectivity. Proteolysis of the precursor envelope glycoprotein gp160 results in the formation of gp120 and gp41. Cleavage occurs after the sequence Arg-Glu-Lys-Arg. This sequence is expected to be a substrate for the cellular protease furin. We examined whether furin is responsible for cleavage of gp160 by using a furin-deficient CHO cell line and the same cell line transfected with furin cDNA. Data obtained from viral transmission assays suggested that furin increased viral infectivity but was not essential for the maturation of gp160, implying that other proprotein processing enzymes also recognize this putative furin cleavage site.
Gu
M
M
Laboratory of Microbial Ecology, National Institute of Dental Research, National Institutes of Health, Bethesda, MD 20892, USA.
Rappaport
J
J
Leppla
S H
SH
D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D045683:Furin; D015686:Gene Products, env / Q000378:metabolism*; D016655:HIV Core Protein p24 / Q000032:analysis; D019302:HIV Envelope Protein gp160; D015497:HIV-1 / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011498:Protein Precursors / Q000378:metabolism*; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins / Q000378:metabolism; D013381:Subtilisins / Q000235:genetics / Q000378:metabolism*
D015686:Gene Products, env; D016655:HIV Core Protein p24; D019302:HIV Envelope Protein gp160; D011498:Protein Precursors; D011994:Recombinant Proteins; D013381:Subtilisins; D045683:Furin