Characterization of the CoACO proteins. (a) Alignment of the deduced amino acid sequences of CoACO1 and CoACO2 with grape ACO 1–3 proteins. Amino acid position numbers are indicated to the right of the sequence. (b) Putative domain analysis of the CoACO1 and CoACO2 proteins. The conserved domain of the PLN0229 super family was marked with red rectangles. (c) Phylogenetic analysis of the ACO protein family. A maximum-likelihood phylogenetic tree was constructed using the ACO protein sequences from Arabidopsis thaliana (At), Vitis vinifera (Vv), Solanum lycopersicum (Sl), sorghum bicolor (Sb) and Oryza sativa (Os). The 16 proteins were clustered into the three distinct groups indicated. The accession numbers of ACO proteins in GenBank are: CoACO1 (MW854295), CoACO2 (MW854296), AtACO1 (NP_179549), AtACO2 (NP_176428), AtACO3(NP_172665), AtACO4 (NP_171994), AtACO5 (NP_565154), OsACO1 (XP_015611803), VvACO1 (AAO37687), VvACO2 (NP_001267871), VvACO3 (AFU66006), SlACO1 (NP_001234024), SlACO2 (P07920), SlACO4 (NP_001233928), SlACO5 (NP_001234037), SbACO1 (XP_002439286). All amino acid sequences were retrieved from GenBank databases.