Fig. 1

Phylogenetic tree of ATP-binding cassette (ABC) transporters of Papilio xuthus (Px), Bombyx mori (BGIBM) and Drosophila melanogaster (CG). The maximum likelihood tree was calculated on the basis of multiple alignments of the ABC transporter protein sequences. All ABCs were clustered into eight subfamilies (ABCA-H). The green pentagrams represent the genes belongs to the P. xuthus, the blue circles indicate the genes among B. mori, and the orange boxs show the genes in the genome of D. melanogaster. Four Px genes highlighted in grey in ABCG subfamily were selected to investigate their function in the development of P. xuthus via CRISPR/Cas9 gene-editing technology