Figure 2.

HYD gene family structure and phylogeny. A, Gene organizational structure showing paralogs and orthologs of the HYD gene family in maize (Zm) and rice (Os) species representing two subfamilies of the Poaceae (grasses). Boxes and lines indicate exons and introns, respectively, sizes for which are in bp. Vertical lines connecting paralogs represent a subfamily. B, Phenetic analysis showing the evolution and duplication of carotenoid hydroxylase amino acid sequences. Monocot sequences fall into two major groups labeled 1 and 2. GenBank accessions are in parentheses: Erwinia (crtZ AAA64983), Arabidopsis (βOHase1, AT4G25700; βOHase2, AT5G52570), tomato (Solanum lycopersicum; crtR-b1, Y14809; crtR-b2, Y14810); “Materials and Methods” and Supplemental Table S1 list monocot accession numbers. [See online article for color version of this figure.]