Analysis of the sucrose synthase (SUS) gene family in wheat (Triticum aestivum L.) based on bioinformatics methods

In higher plants, sucrose synthase (SuS, EC 2.4.1.13) is widely considered as a key enzyme involved in sucrose metabolism and catalyzes the reversible cleavage of sucrose into fructose and UDP- glucose. Here, 22 SuS genes have been identified in the genome of wheat by using bioinformatics methods and renamed TaSUS1 to TaSUS22 according to their chromosomal locations. Phylogenetic analysis revealed that the sucrose synthase genes in wheat and other plants were divided into three evolutionary groups, named SUS I, SUS II and SUS III, respectively. SuS genes in the same group showed similar structural characteristics, such as exon number, size and length distribution. The upstream regions of TaSuS genes had variable frequencies of cis-regulatory elements that could show regulation at different developmental stages and/or differential regulation in response to stress, while 21 genes had targets for 16 different miRNA families that show the importance of posttranscriptional regulation for TaSUS genes. Temporal and spatial expression profiling indicates a potential role for SUSI genes during growth and development in wheat. These results give new insights into the evolution and basic information that will aid in elucidating the functions of the wheat SuS gene family.