Figure 5. Features of the Mot1-bound ‘substrate’ complex.
(A) Comparison of the ‘product’ (left, Wollmann et al., 2011), ‘substrate’ (right, Kamada et al., 2001), and Mot1-bound ‛substrate’ complex (center). Mot1's latch in the latter structure is disordered and represented schematically. Color code is as in Figure 4. Panel (B) shows Mot1NTD and TBP from the Mot1NTD:TBP:DNA:NC2 structure (color code as in Figure 4) superimposed via TBP with the ‘product’ Mot1NTD:TBP structure and NC2β H5 from the ‘substrate’ TBP:DNA:NC2 structure (both shown in light brown). Mot1NTD shifts toward H5 and TBP although the position of H5 is not affected. Panels (C) and (D) show conformational changes of NC2 and DNA in the Mot1NTD:TBP:DNA:NC2 complex structure (color code as in Figure 4) compared to the TBP:DNA:NC2 ‘substrate’ complex (shown in light brown) superimposed via TBP. (C) View from the concave side of TBP shows that in the presence of Mot1, DNA is partially straightened and underwound. TATA box region is highlighted in red. Panel (D) shows that partially unfolded helix H4 of NC2β, which joins the NC2HF with helix H5, loses its interaction with downstream DNA and is close to TBP's C-terminal stirrup.
Figure 5—figure supplement 1. Mot1NTD:TBP:DNA:NC2 structure features.
