Analysis of a human immunodeficiency virus type 1 isolate carrying a truncated transmembrane glycoprotein.
We have recently reported the isolation of a human immunodeficiency virus type 1 (HIV-1), KB-1gp32 carrying a shorter size (32 kDa) of transmembrane glycoprotein (TMP) from TALL-1 cells persistently infected with KB-1gp41 virus strain (Shimizu et al., 1990a). Endoglycosidase treatments showed that the different size of the TMP between the two strains was due to a truncation of 9 kDa of polypeptide in the KB-1gp32 TMP coding region. Sequence analysis revealed the substitution of a CAG codon to a TAG stop codon just downstream of the putative membrane-spanning domain of the TMP of KB-1gp32. This resulted in a truncation of some 133 amino acids of the cytoplasmic domain of TMP. The data indicate that a premature stop codon in KB-1gp32 has been introduced during adaption of the parental virus to TALL-1 cells. We have constructed two chimeric clones between the env region of a clone pKB-1, derived from KB-1gp32, and an infectious molecular clone pNL-432. We have also constructed a site-directed mutant of pNL-432 carrying a premature stop codon at the same position as the env stop codon of pKB-1. Among the three clones carrying a premature stop codon in env, only one chimeric clone was infectious to TALL-1 but not MT-2 cells. This clone contained the entire tat, rev, vpu, and env genes of pKB-1. The pNL-432 mutant was not infectious. The results suggest that some sequences of pKB-1 might compensate for the truncation of the TMP during replication in TALL-1 cells.
Shimizu
H
H
AIDS Research Center, National Institute of Health, Tokyo, Japan.
Hasebe
F
F
Tsuchie
H
H
Morikawa
S
S
Ushijima
H
H
Kitamura
T
T
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D003593:Cytoplasm; D015752:Genes, env; D015700:HIV Envelope Protein gp41 / Q000737:chemistry* / Q000235:genetics; D015497:HIV-1 / Q000737:chemistry* / Q000235:genetics; D016086:Lentivirus / Q000737:chemistry / Q000235:genetics; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D014162:Transfection
D015700:HIV Envelope Protein gp41; D008562:Membrane Glycoproteins; D009838:Oligodeoxyribonucleotides