DNA Recognition by Eucaryotic Transcription Factors

  • The TATA box-binding protein was first isolated and purified from yeast in 1988 - with a MW of 27 kDa.
  • The C-terminal domain contains

    • - all the functions essential for normal yeast cell growth.
    - two homologous repeats of 88 amino acids
    - binds to TATA consensus sequence with a Kd in the
      nanomolar range.
  • Two similar domains form a saddle-shaped molecule with stirrups.
  • A b sheet in TBP forms the DNA-binding site

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  • TBP binds in the minor groove and  induces large structural changes in DNA



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  • induces DNA bending ~ 100 degrees.
  • The interaction area between TBP and TATA box is mainly hydrophobic
  • The only sequence-specific hydrogen bonds between TBP side chains and the bases in the minor groove occur at the very center of the TATA box.



  • Functional implications of the distortion of DNA by TBP
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