Plays a central role as a glucosyl donor in cellular metabolic pathways. alpha-D-glucose 1-phosphate + H(+) + UTP = diphosphate + UDP-alpha-D-glucose Expressed in both prestalk and prespore cells. Expression becomes strong after 12 hours of development and peaks at 16 hours. Cells undergo aberrant differentiation and development ending with small, gnarled fruiting bodies. They also have decreased spore viability and decreased levels of glycogen. Belongs to the UDPGP type 1 family.