Protein trees of the various membrane transporters of Na+and K+. The protein trees are labelled according to the names of homologues from S. cerevisiae (except Acu transporters, which have no S. cerevisiae homologues). The trees (except for Acu) were rooted with homologous proteins from C. neoformans (Trk: [GenBank:XP_570017], [GenBank:XP_569339]; Tok: [GenBank:XP_568987], [GenBank:XP_568988]; Nha: [GenBank:XP_569560]; Ena: [GenBank:XP_572412], [GenBank:XP_568029], [GenBank:XP_570160]; Pho: [GenBank:XP_568082]) and root locations marked with an arrow. In addition to genes from A. pullulans, homologues from related fungi were used, as labelled with the fungal species name and GenBank accession number (H. werneckii, M. graminicola, S. cerevisiae), or the Joint Genome Institute Genome Portal protein ID (all of the rest). Putative gene duplications leading to the present diversity of these genes in A. pullulans are indicated by double arrows. ApP, A. pullulans var. pullulans; ApS, A. pullulans var. subglaciale; ApN, A. pullulans var. namibiae; ApM, A. pullulans var. melanogenum.