Genome-wide characterization of protein phosphatase 2C genes in Populus euphratica and their expression profiling under multiple abiotic stresses

Abstract

The protein phosphatase 2Cs (PP2Cs) have been demonstrated to act as negative modulators of protein kinase and to participate in stress signal transduction, as well as plant growth and productivity processes. Populus euphratica is so extraordinarily adaptable to abiotic stresses that it is regarded as a potential model plant for exploring resistance mechanisms of woody plants. To gain insight into the functional characteristics of PP2C genes in P. euphratica, 117 non-redundant PeuPP2C-encoding genes were identified from the whole genome. These members were classified into 13 groups (A–M), each of which was relatively conserved in gene structure and protein domain. A total of 39 paralogous pairs were found to be generated by whole genome duplication events, and Ka/Ks analysis indicated that these paralogous pairs had evolved mainly from purifying selection. The cis-acting elements and expression patterns showed that all the PeuPP2Cs were involved in response to single or multiple stresses including drought, salinity, heat, cold, and ABA. Taken together, our results summarized the genome-wide characterization of PeuPP2Cs and their expression profiling across different tissues and under multiple abiotic stresses in P. euphratica. These data provide a foundation to further investigate potential function of PeuPP2Cs in conferring tolerance to various stresses in P. euphratica.