Figure 2.

Arabidopsis thaliana ATP-binding cassette (ABC) protein subfamilies, with their maximum likelihood phylogenies, and a phylogeny of the NBDs of all Arabidopsis ABC proteins.

For the ABCI subfamily, only the encoded domain is indicated, as their divergence is too large to resolve their phylogenetic relationships. In the NBD phylogeny, both NBDs of full-size ABCs were included. NBDs of full-size ABCB show little divergence compared to NBDs of ABCCs and full-size ABCGs. Phylogenies were estimated using PhyML3.0 (Guindon et al., 2010) and the model LG+G4+I+F from a truncated protein sequence alignment generated with MUSCLE 3.8 (http://www.drive5.com/muscle). Gaps of more than 80% were removed (Capella-Gutiérrez et al., 2009). Branch support values correspond to non-parametric bootstrap values from 100 replicates. Domain organizations are indicated by colored symbols (key, bottom right).