Fig. 1.

Schematic of the predicted topology of plant CESAs and protein sequence alignment of the computationally modelled region. (A) Plants CESAs are predicted to have eight transmembrane helices (TMHs) with the cytosolic domain between TMH2 and 3, which contains the active site. The TMH5–6 region, which was modelled, is shown within the black box, including the two TMHs and the amino acids between them. Missense mutations within this region are highlighted with arrows. bc=brittle culm, ixr=isoxaben resistant, mre=multiple response expansion. (B) Protein sequence alignment of the modelled TMH5–6 region of AtCESA1, 3, 6 and BcsA is shown, along with homologous sequences of AtCESA2, 4, 5, 7, 8, and 9. Orange circles indicate the mre1, F954L, and ixr1-2 missense mutations. Blue shading indicates TMHs and green shading represents IF3 in BcsA. (C) A snapshot of GhCESA1 coloured to represent protein sequence conservation based on results from a BLAST search of amino acids 820–890. Blue indicates 100% sequence conservation, white indicates 72% conservation, and red indicates 30% sequence conservation. The snapshot was generated using Chimera software (Pettersen et al., 2004). For a list of protein sequences used to create this snapshot, please see Supplementary Table S2.