Location of amino acid substitutions in Tub2p
suppressors. Tub2p is shown in white; adjacent Tub1p monomers of the
protofilament are shown in yellow (Richards et al.,
2000). Amino acids changed in Tub2p suppressors are indicated in blue.
GTP is shown in green. The following amino acid substitutions in Tub2p
were found to suppress stu1–5: G17C, G17D, W59L, V66F,
Q94K, S95R, A102S, V116A, H137N, T149 M, C211F, G223R, F265I, and
E288A. C211F was obtained four times; Q94R, S95R, and H137N were each
obtained twice; all others were obtained once. Orientation axes: +
and − show microtubule orientation; H3 and M show lateral sides
marked by the H3 α-helix and M loop, respectively; in and out
represent the inside and outside of the microtubule. Structure drawn
with RASMOL (Sayle and Milner-White, 1995).