GLUT3

GLUT3 is a glucose transporter within cell membranes. It is one of 14 Na⁺ independent facilitated diffusion transporters^[1], termed GLUT1 to GLUT14. As it is a facilitated diffusion transporter, it relies on a concentration gradient for transport of glucose.

GLUT3 binds to glucose in the extracellular space (e.g. blood) which induces a conformational change. This conformational change transports the glucose across the cell membrane.

GLUT3 is primarily involved in glucose transport for neurones^[2] and, unlike some transporters, principally tranports glucose to within the cells, rather than bidirectionally.

Another role of GLUT3 that has been investigated is it's part in early embryonic development, as research indicates that if the gene encoding the GLUT3 protein is deleted, then there is severe development issues and problems^[3].

References

1. ↑ Cura, Anthony J., and Anthony Carruthers. “The Role of Monosaccharide Transport Proteins in Carbohydrate Assimilation, Distribution, Metabolism and Homeostasis.” Comprehensive Physiology 2.2 (2012): 863–914. PMC. Web. 6 Dec. 2017.
2. ↑ Expression of two glucose transporters, GLUT1 and GLUT3, in cultured cerebellar neurons: Evidence for neuron-specific expression of GLUT3.fckLRF. Maher, T. M. Davies-Hill, P. G. Lysko, R. C. Henneberry, I. A. SimpsonfckLRMol Cell Neurosci. 1991 Aug; 2(4): 351–360.
3. ↑ Schmidt, S et al. “Essential Role of Glucose Transporter GLUT3 for Post-Implantation Embryonic Development.” The Journal of Endocrinology 200.1 (2009): 23–33. PMC. Web. 6 Dec. 2017.