Document 3287
 DOCN  M94A3287
 TI    Maturation of the HIV gp160 by the Kex2p endoprotease.
 DT    9412
 AU    Moulard M; Kieny MP; Achsterrer T; Montagnier L; Bahraoui E; Universitat
       Marburg, Germany.
 SO    Int Conf AIDS. 1994 Aug 7-12;10(1):110 (abstract no. PA0058). Unique
       Identifier : AIDSLINE ICA10/94369288
 AB    OBJECTIVE: To study the in vitro processing of HIV-1 envelope protein
       precursor, Kex2p endoprotease from Saccaromyces cerevisiae was used as a
       model. METHODS: Maturation was examined by using HIV-1 recombinant gp160
       or synthetic peptides mimicking the potential cleavage sites of HIV-1,
       HIV-2 and SIV. The effect of calcium on the gp160 cleavage was
       investigated in the presence of the ionophore A 23187. RESULTS: The
       precursor gp160 is cleaved in the HIV-1 CEM cell line preferentially in
       the presence of calcium ions indicating that the responsible cellular
       endoprotease is a calcium dependent enzyme. Treatment of recombinant
       gp160 with Kex2p endoprotease and analysis by Western blot showed that
       this precursor was cleaved into two products corresponding to the
       external transmembrane and transmembrane glycoproteins. Amino acid
       sequencing of the NH2 terminus of the transmembrane protein showed that
       the cleavage of gp160 occured correctly between Arg511 and Arg512.
       Similar results were obtained when synthetic peptides were used as
       substrates. Furthermore coexpression in BHK-21 cells of Kex2p and gp160
       by recombinant vaccinia viruses demonstrates that Kex2p can correctly
       process the HIV-1 glycoprotein to gp120 and gp41. DISCUSSION AND
       CONCLUSIONS: Kex2p endoprotease represents an interesting models to
       screen drugs and inhibitors able to block the processing of HIV-1 gp 160
       which represents a key step in HIV-1 viral cycle.
 DE    Binding Sites  Calcimycin/PHARMACOLOGY  Calcium/METABOLISM  Cell Line
       Gene Products, env/*METABOLISM  Human  HIV Envelope Protein
       gp120/METABOLISM  HIV Envelope Protein gp41/METABOLISM  HIV-1/GROWTH &
       DEVELOPMENT/*METABOLISM  HIV-2/METABOLISM  In Vitro  Models, Biological
       Peptides/CHEMICAL SYNTHESIS/METABOLISM  Protein Precursors/*METABOLISM
       Protein Processing, Post-Translational  Saccharomyces
       cerevisiae/ENZYMOLOGY  Substrate Specificity  Subtilisins/*METABOLISM
       SIV/METABOLISM  MEETING ABSTRACT

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).