Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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.
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PMID:New human gene encoding a positive modulator of HIV Tat-mediated transactivation. 137 63

The acidic transcriptional activation motif functions in all eukaryotes, which suggests that it makes contact with some universal component of the transcriptional apparatus. Transcriptional activation by the yeast regulatory protein GAL4 requires an acidic region at its carboxyl terminus. Here we implement a selection scheme to determine whether GAL4 can still function when this C-terminal domain has been deleted. It can, when accompanied by a mutation in the SUG1 gene which is an essential gene in yeast. Analysis of mutant SUG1 in combination with various alleles of GAL4 indicates that SUG1 acts through a transcriptional pathway that depends on GAL4, but requires a region of GAL4 other than the C-terminal acidic activation domain. The predicted amino-acid sequence of SUG1 closely resembles that of two human proteins, TBP1 and MSS1, which modulate expression mediated by the human immunodeficiency virus tat gene.
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PMID:Alterations in a yeast protein resembling HIV Tat-binding protein relieve requirement for an acidic activation domain in GAL4. 146 48