Department of Biochemistry and Molecular Biology, Molecular Epigenetics, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, B.C. Canada.
Published: September 2011
AI Article Synopsis
Article Abstract
Transcription from the HIV-1 long terminal repeat (LTR) is mediated by numerous host transcription factors. In this study we characterized an E-box motif (RBE1) within the core promoter that was previously implicated in both transcriptional activation and repression. We show that RBE1 is a binding site for the RBF-2 transcription factor complex (USF1, USF2, and TFII-I), previously shown to bind an upstream viral element, RBE3. The RBE1 and RBE3 elements formed complexes of identical mobility and protein constituents in gel shift assays, both with Jurkat T-cell nuclear extracts and recombinant USF/TFII-I. Furthermore, both elements are regulators of HIV-1 expression; mutations in LTR-luciferase reporters and in HIV-1 molecular clones resulted in decreased transcription, virion production, and proviral expression in infected cells. Collectively, our data indicate that RBE1 is a bona fide RBF-2 binding site and that the RBE1 and RBE3 elements are necessary for mediating proper transcription from the HIV-1 LTR.
In recent years, single-atom catalysts (SACs) with separated active centers and high atom utilization have grown significantly as a significant area of catalytic research. In catalytic applications, SACs of various kinds have demonstrated exceptional performance, so the study of the catalytic mechanism of SACs provides a clearer direction for the preparation of catalysts with high performance. Strong linkages between the single atoms and the support are necessary to overcome the tendency of single atoms to aggregate into clusters, which is called metal-support interaction (MSI).
Background: TPM3 (tropomyosin 3) is an actin-binding protein in vascular smooth muscle cells, where posttranslational modifications critically regulate its actin affinity, influencing cardiovascular function. Emerging evidence suggests that Khib (2-hydroxyisobutyrylation) plays a significant role in the cardiovascular system. Histone deacetylase 3 (HDAC3) serves as an "eraser" of Khib marks.
Stenotrophomonas maltophilia is an emerging global opportunistic pathogen that causes nosocomial infections. We demonstrated that the superoxide stress-sensing transcriptional regulator SoxR directly modulated the expression of an operon encompassing sodA1 (encoding manganese-containing superoxide dismutase) and fre (encoding putative flavin reductase) by directly binding to the operator site, which was located between the - 35 and -10 motifs of the sodA1 promoter. It is known that upon exposure to the superoxide generators/redox-cycling drugs, the SoxR, which is bound to the operator site, became oxidized.
Laboratory of Molecular Medicine, Ordos Central Hospital, Inner Mongolia Autonomous Region, Ordos 017000, China; Ordos Clinical Medical College, Inner Mongolia Medical University, Ordos 017000, China; Baotou Medical College, Inner Mongolia University of Science and Technology, Baotou 014000, China. Electronic address:
Salivary proteins of ticks can inhibit host hemostatic and inflammatory responses during the blood-sucking process of the parasites. A cDNA sequence, Hq021, was identified from a cDNA library of Haemaphysalis qinghaiensis. Hq021 encodes a mature protein containing 182 amino acids with a molecular mass of 20.
tRNA-derived stress-induced RNAs (tiRNAs) are a new class of small non-coding RNA that have emerged as important regulators of cellular stress responses. tiRNAs are derived from specific tRNA cleavage by the stress-induced ribonuclease angiogenin (ANG). Loss-of-function mutations in the ANG gene are linked to amyotrophic lateral sclerosis (ALS), and elevated levels of specific tiRNAs were recently identified in ALS patient serum samples.
