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Author of comparative research on human and rat pancreatic beta cells. The study distinguished differences in glucose transporter expression from glucokinase expression, helping specify which parts of glucose sensing vary between species.^[ref]

A glucose transporter is a membrane transport protein that moves glucose across a cell membrane. The category includes facilitated transporters such as GLUT1 and GLUT4, and coupled carriers such as SGLT1. A facilitated transporter allows movement down a glucose chemical-potential difference; a sodium-coupled carrier can use the sodium electrochemical gradient to accumulate glucose. ^[ref]

For GLUT4, changing surface abundance is itself a regulatory mechanism. Insulin-responsive trafficking can deliver pre-existing carriers to the surface, increasing transport without first synthesizing more transporter. The amount of protein in the whole cell and the amount available at its outer boundary therefore need not change together. ^[ref]