CAO Jinlong, WANG Li, CAO Lingfang, HAO Kaiyin, GU Jiliang, WANG Yu, CHE Zhijun
OFP is a class of plant-specific transcription factors that play important roles in the regulation of plant organ morphogenesis and response to abiotic stresses.In order to study the characterization of soybean OFP transcription factor family members and their roles in drought stress and salt stress,bioinformatics methods were applied to identify and analyze soybean OFP family members.The results showed that:a total of 41 GmOFPs,named GmOFP-1—GmOFP-41,were identified in soybean;these genes were unevenly distributed on 19 chromosomes of soybean,encoding 152—414 amino acids;subcellular localization predicted that soybean OFP proteins were mainly localized in nucleus,chloroplasts,and mitochondria;a total of 10 conserved motifs were identified in soybean OFP proteins,conservative Motifs 1 and 2 were present in all OFP members.Phylogenetic analysis classified soybean and Arabidopsis OFP proteins into five subfamilies ClassⅠ—Class V,of which soybean OFP family genes were mainly distributed in ClassⅠ and Class Ⅲ.The collinearity analysis revealed that 75 pairs of genes in the soybean genome had collinearity,four pairs of genes had tandem duplications,and only two genes,GmOFP-2 and GmOFP-39,did not have collinearity,which indicated that gene fragment duplication was the main reason for the increase in the number of soybean OFP family members.The expression patterns of GmOFP gene family members under drought stress and salt stress treatments were analyzed by qRT-PCR,and the results showed that,compared with the control,16 members out of 41 GmOFP genes exhibited significant differences in gene expression levels after drought treatments,with significant up-regulation of the expression of GmOFP-15,GmOFP-17,and GmOFP-32,while the GmOFP-4,GmOFP-5,GmOFP-6,GmOFP-9,GmOFP-12,GmOFP-21,GmOFP-23,GmOFP-25,GmOFP-26,GmOFP-27,GmOFP-38,GmOFP-39,and GmOFP-40 were significantly down-regulated after drought treatment.Eight members of GmOFPs showed significant differences in gene expression levels after salt treatment,among which GmOFP-7,GmOFP-14,GmOFP-31,GmOFP-32,GmOFP-36,and GmOFP-40 were significantly up-regulated,and GmOFP-1 and GmOFP-15 were significantly down-regulated.The above results suggest that the soybean OFP gene family may have important functions in response to drought stress and salt stress.