In order to confirm that CsMRP4 belongs to a MRP subfamily and to infer its phylogenetic relationship with the ABCC and ABCB subfamilies, 12 canonical ABCC proteins and 11 canonical ABCB proteins were retrieved from UniProtKB/Swiss-Prot v. 2017_07 . Multiple sequence alignment was performed using the L-INS-i method of MAFFT v. 7.299 . An evolutionary history was inferred by employing the neighbor-joining (NJ) method using MEGA v. 6.06 . All the positions containing gaps and missing data were eliminated.