Fig. 1.

Identification of NCH1 as a phototropin-signaling component. (A) Protein structure of NCH1. Four conserved regions I to IV (black boxes) and a BTB/POZ domain (black bar) are indicated. N- and C-terminal regions that are used in yeast two-hybrid assay are indicated below. (B) Gene structure and mutation sites of RPT2, NCH1, and NCL1 genes. The rectangles and the intervening bars indicate exons and introns, respectively. The white rectangles and bars in the NCL1 gene indicate the predicted exon and intron sequences, respectively, which are similar to those of NCH1 but were deduced to be noncoding. The positions of the T-DNA insertion sites and the point mutation are indicated. (C) A RPT2/NCH1 clade in the NRL protein phylogenetic tree. The full NRL protein phylogenetic tree is presented in Fig. S2. Bar indicates 0.5 substitutions per site. AT, Arabidopsis thaliana; AmTr, Amborella trichopoda; MA, Picea abies; Smoe, Selaginella moellendorfii; Phpat, Physcomitrella patens; and Mapoly, Marchantia polymorpha.