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  • The EMBO Journal (2001) 20, 2028 - 2040
  • doi:10.1093/emboj/20.8.2028

MOT1-catalyzed TBP–DNA disruption: uncoupling DNA conformational change and role of upstream DNA

Russell P. Darst1, Dongyan Wang1 and David T. Auble1

  1. Department of Biochemistry and Molecular Genetics, University of Virginia Health Science Center, 1300 Jefferson Park Avenue, Room 6213, Charlottesville, VA 22908-0733, USA

Correspondence to:

David T. Auble, E-mail: dta4n@virginia.edu

Received 21 September 2000; Accepted 27 February 2001; Revised 30 January 2001

SNF2/SWI2-related ATPases employ ATP hydrolysis to disrupt protein–DNA interactions, but how ATP hydrolysis is coupled to disruption is not understood. Here we examine the mechanism of action of MOT1, a yeast SNF2/SWI2-related ATPase that uses ATP hydrolysis to remove TATA binding protein (TBP) from DNA. MOT1 function requires a 17 bp DNA 'handle' upstream of the TATA box, which must be double stranded. Remarkably, MOT1-catalyzed disruption of TBP–DNA does not appear to require DNA strand separation, DNA bending or twisting of the DNA helix. Thus, TBP–DNA disruption is accomplished in a reaction apparently not driven by a change in DNA structure. MOT1 action is supported by DNA templates in which the handle is connected to the TATA box via single-stranded DNA, indicating that the upstream duplex DNA can be conformationally uncoupled from the TATA box. Combining these results with proposed similarities between SNF2/SWI2 ATPases and helicases, we suggest that MOT1 uses ATP hydrolysis to translocate along the handle and thereby disrupt interactions between TBP and DNA.

  • Keywords:

    • ATPase,
    • MOT1,
    • TBP,
    • transcription