transport protein (variously referred to as a transmembrane pump, transporter, escort protein, acid transport protein, cation transport protein, or anion transport protein) is a protein that serves the function of moving other materials within an organism. Transport proteins are vital to the growth and life of all living things. There are several different kinds of transport proteins. Carrier proteins are proteins involved in the movement of ions, small molecules, or macromolecules, such as another protein, across a biological membrane.[1] Carrier proteins are integral membrane proteins; that is, they exist within and span the membrane across which they transport substances. The proteins may assist in the movement of substances by facilitated diffusion (i.e., passive transport) or active transport. These mechanisms of movement are known as carrier-mediated transport.[2] Each carrier protein is designed to recognize only one substance or one group of very similar substances. Research has correlated defects in specific carrier proteins with specific diseases.[3] A membrane transport protein (or simply transporter) is a membrane protein[4] that acts as such a carrier. [from: Wikipedia contributors. (2019, May 9). Transport protein. In Wikipedia, The Free Encyclopedia. Retrieved 18:43, June 6, 2019, from https://en.wikipedia.org/w/index.php?title=Transport_protein&oldid=896329420]

Glucose transporter 2 (GLUT2) also known as solute carrier family 2 (facilitated glucose transporter), member 2 (SLC2A2) is a transmembrane carrier protein that enables protein facilitated glucose movement across cell membranes. It is the principal transporter for transfer of glucose between liver and blood [5] Unlike GLUT4, it does not rely on insulin for facilitated diffusion. GLUT2 has high capacity for glucose but low affinity (high Km, ca. 15-20 mM) and thus functions as part of the "glucose sensor" in the pancreatic β-cells of rodents, though in human β-cells the role of GLUT2 seems to be a minor one.[10] It is a very efficient carrier for glucose.[11][12] GLUT2 also carries glucosamine.[13] When the glucose concentration in the lumen of the small intestine goes above 30 mM, such as occurs in the fed-state, GLUT2 is up-regulated at the brush border membrane, enhancing the capacity of glucose transport. Basolateral GLUT2 in enterocytes also aids in the transport of fructose into the bloodstream through glucose-dependent cotransport.

References:
1) Thorens B, Cheng ZQ, Brown D, Lodish HF. (1990) Liver glucose transporter: a basolateral protein in hepatocytes and intestine and kidney cells. J Am Physiol. 259(2 Pt 1):C279-85.

transport protein (variously referred to as a transmembrane pump, transporter, escort protein, acid transport protein, cation transport protein, or anion transport protein) is a protein that serves the function of moving other materials within an organism. Transport proteins are vital to the growth and life of all living things. There are several different kinds of transport proteins. Carrier proteins are proteins involved in the movement of ions, small molecules, or macromolecules, such as another protein, across a biological membrane.[1] Carrier proteins are integral membrane proteins; that is, they exist within and span the membrane across which they transport substances. The proteins may assist in the movement of substances by facilitated diffusion (i.e., passive transport) or active transport. These mechanisms of movement are known as carrier-mediated transport.[2] Each carrier protein is designed to recognize only one substance or one group of very similar substances. Research has correlated defects in specific carrier proteins with specific diseases.[3] A membrane transport protein (or simply transporter) is a membrane protein[4] that acts as such a carrier. [from: Wikipedia contributors. (2019, May 9). Transport protein. In Wikipedia, The Free Encyclopedia. Retrieved 18:43, June 6, 2019, from https://en.wikipedia.org/w/index.php?title=Transport_protein&oldid=896329420]

Glucose transporter 2 (GLUT2) also known as solute carrier family 2 (facilitated glucose transporter), member 2 (SLC2A2) is a transmembrane carrier protein that enables protein facilitated glucose movement across cell membranes. It is the principal transporter for transfer of glucose between liver and blood [5] Unlike GLUT4, it does not rely on insulin for facilitated diffusion. GLUT2 has high capacity for glucose but low affinity (high Km, ca. 15-20 mM) and thus functions as part of the "glucose sensor" in the pancreatic β-cells of rodents, though in human β-cells the role of GLUT2 seems to be a minor one.[10] It is a very efficient carrier for glucose.[11][12] GLUT2 also carries glucosamine.[13] When the glucose concentration in the lumen of the small intestine goes above 30 mM, such as occurs in the fed-state, GLUT2 is up-regulated at the brush border membrane, enhancing the capacity of glucose transport. Basolateral GLUT2 in enterocytes also aids in the transport of fructose into the bloodstream through glucose-dependent cotransport.

References:
1) Thorens B, Cheng ZQ, Brown D, Lodish HF. (1990) Liver glucose transporter: a basolateral protein in hepatocytes and intestine and kidney cells. J Am Physiol. 259(2 Pt 1):C279-85.