High-affinity DNA binding by a Mot1p-TBP complex: implications for TAF-independent transcription.
Yeast Mot1p, an abundant conserved member of the Snf2p-ATPase family of proteins, both dissociates TBP from DNA in vitro using the energy of ATP and represses gene transcription in vivo, yet paradoxically, loss of Mot1p function also leads to decreased transcription of certain genes. We conducted experiments utilizing fluorescently labeled DNA, TBP, fluorescence anisotropy spectroscopy and native gel electrophoresis to study Mot1p action. We have made a number of observations, the most intriguing being that a stable Mot1p-TBP complex has the ability to bind TATA DNA with high affinity, albeit with dramatically altered specificity. We propose that this altered TBP-DNA recognition is integral to Mot1p's ability to regulate transcription, and further postulate that the Mot1p-TBP complex delivers TBP to TAF-independent mRNA encoding genes.
Gumbs
Orlando H
OH
Department of Molecular Physiology and Biophysics, Vanderbilt University, School of Medicine, Nashville, TN 37232-0615, USA.
Campbell
Allyson M
AM
Weil
P Anthony
PA
D000251:Adenosine Triphosphatases; D000255:Adenosine Triphosphate / Q000378:metabolism; D004247:DNA / Q000235:genetics / Q000378:metabolism*; D004265:DNA Helicases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005454:Fluorescence Polarization; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D046911:Macromolecular Substances; D011485:Protein Binding; D012235:Rhodamines / Q000737:chemistry / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016385:TATA Box; D035381:TATA-Binding Protein Associated Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D035181:TATA-Box Binding Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D005656:Fungal Proteins; D046911:Macromolecular Substances; D012235:Rhodamines; D029701:Saccharomyces cerevisiae Proteins; D035381:TATA-Binding Protein Associated Factors; D035181:TATA-Box Binding Protein; D000255:Adenosine Triphosphate; D004247:DNA; D000251:Adenosine Triphosphatases; C073676:MOT1 protein, S cerevisiae; D004265:DNA Helicases