• Genome-wide identification of 18 sucrose transporter ( AhSUT ) genes in peanut. • Promoters of AhSUT genes contain cis -acting elements related to growth, development, and stress responses. • AhSUT4 localizes to the plasma membrane, cytoplasm and intracellular vesicles. • AhSUT4 overexpression alters plant architecture with increased branching and short siliques. • AhSUT4 enhances leaf sugar accumulation, linking carbon status to growth under stress-relevant contexts. Sucrose transporters (SUTs) play a crucial role in the long-distance transport and partitioning of sucrose in plants, directly modulating growth, development, and stress responses. Although SUT genes have been widely characterized in diverse crops, systematic genome-wide identification and functional analysis of the SUT gene family in peanut ( Arachis hypogaea ) remain limited. In this study, 18 AhSUT genes were systematically identified from the peanut whole-genome sequence and classified them into three major groups based on phylogenetic relationships. Cis -regulatory element analysis showed that the promoter regions of AhSUT genes harbor multiple motifs associated with growth, development, and stress responses. Furthermore, one SUT was isolated from peanut and designated AhSUT4. Subcellular localization assays revealed that AhSUT4 localizes to the plasma membrane, cytoplasm, and vesicles. Heterologous overexpression of AhSUT4 in Arabidopsis significantly promoted branching, producing thinner, clustered branches and shorter siliques relative to wild type. Transgenic plants also accumulated higher levels of total soluble sugars, sucrose, glucose, and fructose than wild-type plants. In summary, this study systematically characterizes the composition, phylogenetic relationships, and expression patterns of the peanut SUT gene family, and clarifies the function of AhSUT4 in sugar accumulation and plant growth and development. These findings provide a molecular foundation for further dissecting the r mechanisms underlying sucrose transport and its regulatory roles in yield formation in peanut.
Cai et al. (Wed,) studied this question.