Genome-Wide Identification and Expression Characteristics of Cytokinin Response Factors in Soybean

The cytokinin response factors (CRFs) take crucial part in mediating plant development and stress response processes. However, hardly any information is known about CRF genes in the main crop plant soybean at present. Here, we carried out genome-wide dissection of CRF family in soybean and identified 26 members, which locate on 18 chromosomes of soybean. Sequence information was first observed to gain insight into the soybean CRF genes. Then, the gene duplication, phylogenetic relationships, protein motifs, and gene structure were analyzed in depth to better understand the CRF family in soybean. Cis -regulatory elements analysis showed that these CRFs contain many hormone- and stress-related elements on promoter regions, indicating their potential involvement in response to these factors. In addition, through investigating the public transcriptome data, we studied the expression patterns of those CRFs in different tissues/organs and various environments. The results revealed that expression of soybean CRFs not only exhibited spatial-diversity, but also differs in response to cold, drought, and salt stress. Our research offers new insights into soybean CRFs as well as useful information for future functional analysis of this gene family.