ABSTRACT
Transcriptional activation of HIV-1 gene expression by the viral Tat protein requires the interaction of a cellular cofactor with the Tat activation domain. This domain has been shown to consist of the cysteine-rich and core motifs of HIV-1 Tat and is functionally conserved in the distantly related Tat proteins of HIV-2 and EIAV. Using the yeast two-hybrid system, we have identified a novel human gene product, termed HT2A, that specifically and precisely binds to the activation domain of HIV-1 Tat and that can also interact with the HIV-2 and EIAV Tat proteins in vivo. We present data further demonstrating that the interaction between the activation domain of HIV-1 Tat and the HT2A protein can be readily detected in the mammalian cell nucleus. Sequence analysis demonstrates that HT2A is a novel member of the C3HC4 or ring finger family of zinc finger proteins that includes several known oncogenes and transcription factors. Overall, these data suggest that HT2A may play a significant role in mediating the biological activity of the HIV-1 Tat protein in vivo.
Subject(s)
Cell Nucleus/metabolism , Gene Products, tat/metabolism , HIV-1/metabolism , HIV-2/metabolism , Transcription Factors/metabolism , Zinc Fingers/physiology , Amino Acid Sequence , Animals , Binding Sites , Cell Line , Chloramphenicol O-Acetyltransferase/analysis , Chloramphenicol O-Acetyltransferase/biosynthesis , Chlorocebus aethiops , DNA, Complementary , HIV-1/genetics , HeLa Cells , Humans , Kidney , Molecular Sequence Data , Recombinant Proteins/analysis , Recombinant Proteins/biosynthesis , Sequence Homology, Amino Acid , Transfection , Tripartite Motif Proteins , Ubiquitin-Protein Ligases , tat Gene Products, Human Immunodeficiency VirusABSTRACT
In the initial experiment, 20 male and 20 female heterogeneous stock (HS) mice were divided randomly into experimental and control groups. Ethanol was administered in liquid diet form to the experimental group in increasing dosages for a 9-day period followed by behavioral and physiological tests to determine differences between groups and genders 6 to 7 hr post-withdrawal. Analysis of data showed significant differences between the ethanol-treated and control groups for at least six of the measures. In addition, significant gender differences and significant interactions between gender ant treatment group were found for four of the measures; in all of these cases, females appeared to exhibit a less severe withdrawal syndrome than males. In a second experiment, no gender difference in rate of ethanol disappearance from the blood could be found in 36 HS mice tested at 1 to 3 hr post-withdrawal.
