Cloning and Biochemical Characterization of TAF-172, a Human Homolog of Yeast Mot1
AUTOR(ES)
Chicca, John J.
FONTE
American Society for Microbiology
RESUMO
The TATA binding protein (TBP) is a central component of the eukaryotic transcriptional machinery and is the target of positive and negative transcriptional regulators. Here we describe the cloning and biochemical characterization of an abundant human TBP-associated factor (TAF-172) which is homologous to the yeast Mot1 protein and a member of the larger Snf2/Swi2 family of DNA-targeted ATPases. Like Mot1, TAF-172 binds to the conserved core of TBP and uses the energy of ATP hydrolysis to dissociate TBP from DNA (ADI activity). Interestingly, ATP also causes TAF-172 to dissociate from TBP, which has not been previously observed with Mot1. Unlike Mot1, TAF-172 requires both TBP and DNA for maximal (∼100-fold) ATPase activation. TAF-172 inhibits TBP-driven RNA polymerase II and III transcription but does not appear to affect transcription driven by TBP-TAF complexes. As it does with Mot1, TFIIA reverses TAF-172-mediated repression of TBP. Together, these findings suggest that human TAF-172 is the functional homolog of yeast Mot1 and uses the energy of ATP hydrolysis to remove TBP (but apparently not TBP-TAF complexes) from DNA.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=108885Documentos Relacionados
- Mot1 activates and represses transcription by direct, ATPase-dependent mechanisms
- Spt3 and Mot1 cooperate in nucleosome remodeling independently of TBP recruitment
- Cloning and characterization of a human DEAH-box RNA helicase, a functional homolog of fission yeast Cdc28/Prp8.
- Cloning and characterization of hOGG1, a human homolog of the OGG1 gene of Saccharomyces cerevisiae
- Mot1 Associates with Transcriptionally Active Promoters and Inhibits Association of NC2 in Saccharomyces cerevisiae