De. Ott et al., ANALYSIS AND LOCALIZATION OF CYCLOPHILIN-A FOUND IN THE VIRIONS OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 MN STRAIN, AIDS research and human retroviruses, 11(9), 1995, pp. 1003-1006
Previous reports have shown that cyclophilin A (CyPA) is found to be s
pecifically associated with human immunodeficiency virus type-1 (HIV-1
) virions and is required for infectivity (Franke et al. Nature 372:35
9; Thali et al, Nature 372:363). We have examined CyPA associated with
HIV-1(MN) virions, Virions from infected human lymphoid cells were an
alyzed by high-pressure liquid chromatography (HPLC), protein sequence
, and immunoblot analysis. At least three forms of CyPA were found: an
unmodified form, an N-terminally modified form, and an N-terminally m
odified form that migrates as a larger isoform on a reducing-SDS polya
crylamide gel, Using a protease digestion procedure, CyPA that is asso
ciated with virions was found to be located inside the viral membrane,
Similar examination of SIVMne produced by HUT-78 human T cells did no
t detect specific incorporation of CyPA into SIV virions, Our results
are consistent with the role of CyPA acting early in the infectious pr
ocess of HIV-1.