Mechanism of action of regulatory proteins encoded by complex retroviruses
Article Abstract:
Complex retroviruses differs from simple retroviruses not only because of their larger coding capacity but also due to their regulation of expression of gene products. This gene regulation depends on the activity of two virally encoded regulatory proteins that resemble the activities of Tat and Rev proteins of HIV-1 virus. These regulatory proteins control the viral gene expression at the transcriptional and posttranslational levels. Retrovirus transcriptional trans-activators exhibits different mechanisms of action while posttranslational gene expression regulation follows a single pathway that involves a conserved cellular factor.
Publication Name: Microbiological Reviews
Subject: Biological sciences
ISSN: 0146-0749
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
Silencers, silencing, and heritable transcriptional states
Article Abstract:
Three copies of the mating-type genes were found at MAT, HML, and HMR loci in a budding yeast Saccharomyces cerevisiae. The gene at the MAT locus was found to be transcriptionally active whereas those in the HML and HMR loci were trancriptionally silent, thus known as the silent mating-type loci and affected by the position effect. Regulatory sequences, called silencers, were identified to act on the HML and HMR loci by repressing the transciption process. Four SIR proteins, histone H4 and an alpha-acetyltransferase likewise were identified as factors in the completion of the repression of HML and HMR.
Publication Name: Microbiological Reviews
Subject: Biological sciences
ISSN: 0146-0749
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
DNA looping
Article Abstract:
DNA loop formation plays an important role in the regulation of DNA metabolism. These cellular processes include transcriptional initiation in the operons of prokaryotic organisms and inhibition of phage systems. In eukaryotic systems, DNA looping was found in steroid hormone receptor proteins and homeodomain proteins. DNA-looped structures were also detected in recombination and replication in both the eukaryotic and prokaryotic cells. DNA loop formation is influenced by the distance between the binding sites, DNA sequence and other proteins which affect conformational behavior in genetic sequencing.
Publication Name: Microbiological Reviews
Subject: Biological sciences
ISSN: 0146-0749
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Architectural transcription factors: proteins that remodel DNA. Molecular basis of human 46X, Y sex reversal revealed from the three-dimensional solution structure of the human SRY-DNA complex
- Abstracts: Quail myoD is regulated by a complex array of cis-acting control sequences. Identification of DNA-binding protein(s) in the developing heart
- Abstracts: Evidence for balancing selection at the major histocompatibility complex in a free-living ruminant. High levels of MHC class II allelic diversity in lake trout from Lake Superior
- Abstracts: Measurements of the distribution of adenylate concentrations and adenylate energy charge across Pseudomonas aeroginosa biofilms
- Abstracts: Screening actinomycetes for extracellular peroxidase activity. Extracellular heme peroxidases in actinomycetes: a case of mistaken identity