The Facilitative Glucose Transporter SLC2A8 Regulates Reproductive Outcomes and Growth Phenotype in Mice

Abstract

Glucose is a primary source of energy for all mammalian cells, and its uptake or exit by the cell is primarily controlled through the presence of specialized gateways, called glucose transporters. The facilitative glucose transporters (GLUTs), structurally-related membrane-spanning glycoproteins encoded by a family of SLC2A genes, are responsible for the uptake of several monosaccharides including glucose, fructose, mannose, galactose and glucosamine [1]. To date, fourteen SLC2A proteins are known to be expressed in human and mouse cells. Although SLC2A proteins possess a high degree of sequence similarity, they differ significantly in their substrate specificity and binding kinetics as well as in their tissue-specific expression and subcellular distribution [1, 2]. The more recently discovered SLC2A8 (also known as GLUT8) binds and transports glucose with a higher affinity and is expressed in human and mouse tissues including the testis, brain, heart, liver, uterus, and ovary [3]. Although the currently available data suggest that SLC2A8 may exist at the level of the plasma membrane or as an intracellular transporter, the physiological significance of SLC2A8 remains poorly understood. In this regard, an interesting study published in the current issue of Biology of Reproduction by Adastra et al. [4] provides novel evidence to suggest that SLC2A8 plays a major role in controlling the reproductive outcomes in both males and females and in the post-natal growth in mice.