Genome-Wide Identification and Characterization of the Soybean Mate Family and Analysis of Their Expression in Response to Aluminum Stress

Multidrug and toxic compound extrusion (MATE) family is a family of proteins that function as fundamental transporters of metabolic and xenobiotic organic cations. Despite their wide distribution in bacteria, archaea and eukaryotes, the functions of MATE proteins are largely unknown. Compared with bacteria and animals, plants have more MATE orthologs but only few have been characterized. Plant MATE transporters have been shown involving in the detoxification of metals and secondary metabolites, and some of them are related to Al-activated root citrate release, iron translocation and phosphorus efficiency, which might be important for plant tolerance to abiotic stresses. Here, we report a genome-wide analysis of the MATE family in soybean (Glycine max). A total of 153 MATE-encoding genes were annotated in soybean from database search, and only 116 MATE have completed sequence and conserved MATE domain. Segmental and tandem duplication contribute to the expansion of soybean MATE genes. Twelve MATE genes that might be involved in soybean response to aluminum stresses were identified and their expression patterns were further investigated in details.