Phylogenetic analysis and expression patterns of GmPAP1-like. (A) Phylogenetic analysis of soybean GmPAP1-like and GmPAP22-like (also named as GmPAP21) with other plant PAPs. The first two letters of each PAP protein label represent the abbreviated species name: As, Astragalus sinicus; At, Arabidopsis thaliana; Gm, Glycine max; Hv, Hordeum vulgare; Ll, Lupinus luteus; Mt, Medicago truncatula; Nt, Nicotiana tabacum; Os, Oryza sativa; Pv, Phaseolus vulgaris; Ta, Triticum aestivum; Zm, Zea mays. The numerals I, II, and III designate the three groups of PAP proteins. Group II was further divided into two subgroups (IIa and IIb). Bootstrap values (%) are indicated for major branches. (B) Expression patterns of soybean GmPAP1-like in response to Pi starvation at different growth stages. *P<0.05. (This figure is available in color at JXB online.)