Sucrose-cleaving enzyme that provides UDP-glucose and fructose for various metabolic pathways. Modulates metabolic homeostasis and directs carbon towards starch synthesis in developing seeds. an NDP-alpha-D-glucose + D-fructose = a ribonucleoside 5'-diphosphate + H(+) + sucrose Associated with plastid membranes during the maturation phase of the seed. Detected in the whole plant but at lower levels. Predominantly expressed in developing siliques. Also detected in the root tip. Detected in the embryo, endosperm and seed coat (at the protein level). Specifically and highly expressed during seed maturation at 12 days after flowering (at the protein level). By anaerobic stress and by glucose. Positively regulated by the NF-Y/HAP transcription factor complex at least composed of NFYB9/LEC1 or NFYB6/L1L and NFYC2/HAP5B in association with DPBF2/BZIP67. Positively regulated by LEC2. No visible phenotype. Diminution of the starch content of developing seeds and increased lipid accumulation early during seed development. Belongs to the glycosyltransferase 1 family. Plant sucrose synthase subfamily. Sequencing errors.