ARL3 is highly conserved across ciliated species. (A) Sequence alignment of deduced amino acid sequences from 11 invertebrate and vertebrate ARL3 orthologues. Alignments were generated using CLC main workbench (version 6.8); the most conserved residues are shown in black, the least conserved are in red. Dashes indicate gaps introduced to optimize the alignment. ARL3 contains five conserved domains including G1, G2, G3, G4, and G5 as labeled in the boxes. Arrowheads indicate missense mutations created in dominant-negative and constitutive-active ARL3 mutants. (B) The phylogenetic tree of ARL3 proteins from invertebrate and vertebrate species as indicated. The neighbor-joining tree was calculated using the MEGA 7 software. Branch length represents evolutionary relatedness. The ARL3 GenBank accession numbers are as follows: Bos
taurus, NP_001033656.1; Ovis aries, NP_001156025.1; Homo sapiens, AAA21654.1; Xenopus laevis, AAH87495.1; Rattus norvegicus, NP_073191.1; Danio rerio, NP_001038373.1; Mus musculus, NP_001342162.1; Caenorhabditis elegans, CAB07583.1; Trypanosoma brucei, AAC32774.1; Leishmania major strain Friedlin, XP_001687211.1; and Chlamydomonas reinhardtii, XP_042925186.1.