Identification of multiple cyclin subunits of human P-TEFb
Article Abstract:
A positive transcription elongation factor b (P-TEFb) may control transition from abortive to productive elongation through phosphorylation of the carboxy-terminal domain (CTD) of the largest subunit of RNA polymerase II. Drosophila P-TEFb has been shown to be a cyclin-dependent kinase (CDK9). Cloning of multiple cyclin subunits of human P-TEFb (T1 and T2) has been carried out. Cyclin T1 and T2 are expressed ubiquitously. Immunoprecipitation and immunodepletion experiments have indicated that cyclin T1 and T2 were associated in a mutually exclusive way with CDK9, almost all of which was associated with one or the other.
Publication Name: Genes & Development
Subject: Biological sciences
ISSN: 0890-9369
Year: 1998
User Contributions:
Comment about this article or add new information about this topic:
Conversion of the omega subunit of Escherichia coli RNA polymerase into a transcriptional activator or an activation target
Article Abstract:
In eukaryotes and in prokaryotes it appears that transcription can be activated by arbitrary contacts between DNA-bound proteins and components of transcriptional mechanisms. The Escherichia coli omega protein, which copurifies with RNA polymerase, can act as a transcriptional activator when covalent linkage to a DNA-binding protein occurs. It seems that the omega protein and RNA polymerase holoenzyme are associated in vivo. Evidence indicates that transcription can be activated by contact between a DNA-bound protein and any subunit of E. coli RNA polymerase.
Publication Name: Genes & Development
Subject: Biological sciences
ISSN: 0890-9369
Year: 1998
User Contributions:
Comment about this article or add new information about this topic:
Amino acid-amino acid contacts at the coopertivity interface of the bacteriophage lambda and P22 repressors
Article Abstract:
The bacteriophage lambda repressor and P22 repressors have been studied. Protein-protein interaction between DNA-bound dimers mediates cooperativity in which the repressors bind to adjacent and artificially separated operator sites. A genetic approach has been used to identify pairs of amino acids that interact at the dimer-dimer interface. Individual substitutions stop the interaction of the DNA-bound dimers, but changes in combination bring back interaction of lambda cI and P22c2 dimers.
Publication Name: Genes & Development
Subject: Biological sciences
ISSN: 0890-9369
Year: 1998
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Mutation rate in human microsatellites: influence of the structure and length of the tandem repeat. Unraveling autism
- Abstracts: LODs past and present. Regulation of DNA polymerase exonucleolytic proofreading activity: studies of bacteriophage T4 "antimutator" DNA polymerases
- Abstracts: Stereospecific preparation of an excitatory amino acid antagonist with D-hydantoinase from Agrobacterium tumefaciens as a biocatalyst
- Abstracts: Derivation and characterization of a somatic cell hybrid containing the portion of mouse chromosome 11 (MMU11) homologous to human chromosome 17q
- Abstracts: Quantification of bias related to the extraction of DNA directly from soils. Phylogenetic analysis of nonthermophilic members of the kingdom Crenarchaeota and their diversity and abundance in soils