The amino acid sequences of all the A. thaliana ABCI proteins and H. brasiliensis latex proteins were aligned using the MUSCLE program and subjected to phylogenetic analysis by the distance with neighbor-joining method using MEGA 5.05 software. The numbers on the nodes indicate the bootstrap values after 1000 replicates. The scale bar indicates the estimated number of amino acid substitutions per site. Accession numbers for the A. thaliana sequences are AtABCI1 (NP_176516.1), AtABCI2 (NP_085482.1), AtABCI3 (NP_085546.2), AtABCI4 (NP_565344.2), AtABCI5 (NP_973435.1), AtABCI6 (NP_187678.1), AtABCI7 (NP_564404.1), AtABCI8 (NP_192386.1), AtABCI9 (NP_680390.1), AtABCI10 (NP_195072.2), AtABCI11 (NP_196914.1), AtABCI12 (NP_566688.4), AtABCI13 (NP_564850.1), AtABCI14 (NP_973869.1), AtABCI15 (NP_566659.1), AtABCI16 (NP_181270.1), AtABCI17 (NP_176961.1), AtABCI18 (NP_563693.1), AtABCI19 (NP_563694.1), AtABCI20 (NP_195847.1), and AtABCI21 (NP_199224.1). AtSKD1 (AEC08019.1) and HbSKD1 (AIN75626.1) were used as outgroups. The H. brasiliensis latex ABC proteins are marked with a dot.