New human gene encoding a positive modulator of HIV Tat-mediated transactivation.
The human immunodeficiency virus-1 (HIV-1) protein Tat is a potent activator of virus gene expression. Tat functions through a sequence known as TAR, located immediately downstream of the transcription start site in the long terminal repeat. Several observations suggest that cellular factors cooperate with Tat in the overall transactivating process. We have isolated a human complementary DNA from the new gene MSS1, which may encode such a cellular factor, by transcomplementation of a yeast sgv1- mutant. The MSS1 protein shares 42% sequence identity with the human TBP-1 protein, which binds Tat in vitro and suppresses Tat-mediated transactivation in vivo (ref. 6). We report here that the levels of HIV activation by Tat correlate with endogenous levels of MSS1 messenger RNA. Furthermore, we provide evidence that expression of MSS1 enhances the Tat-mediated transactivation. Our results suggest that MSS1 has a key role in activation of HIV genes regulated by Tat.
Shibuya
H
H
Institute for Molecular and Cellular Biology, Osaka University, Japan.
Irie
K
K
Ninomiya-Tsuji
J
J
Goebl
M
M
Taniguchi
T
T
Matsumoto
K
K
D000074183:ATPases Associated with Diverse Cellular Activities; D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D002460:Cell Line; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D015967:Gene Expression Regulation, Viral; D015696:Gene Products, tat / Q000235:genetics / Q000378:metabolism; D016356:Gene Products, tax / Q000235:genetics / Q000378:metabolism; D016355:Genes, pX; D015756:Genes, tat; D015497:HIV-1 / Q000235:genetics*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D046988:Proteasome Endopeptidase Complex; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012091:Repetitive Sequences, Nucleic Acid; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D015533:Transcriptional Activation; D014162:Transfection; D054322:tat Gene Products, Human Immunodeficiency Virus
D004268:DNA-Binding Proteins; D015696:Gene Products, tat; D016356:Gene Products, tax; D054322:tat Gene Products, Human Immunodeficiency Virus; C075363:PSMC2 protein, human; D012313:RNA; D015500:Chloramphenicol O-Acetyltransferase; D046988:Proteasome Endopeptidase Complex; D000074183:ATPases Associated with Diverse Cellular Activities