Sensor not transporter

摘要

We all know that glucose occupies a central position in cellular earbon and energy metabolism. However, glucose has another little-known function; it also works as a signalling molecule regulating food intake. body weight, blood glucose levels and gastrointestinal reflexes. Which poses the question, are eukaryotic cells able 10 sense external glucose concentrations directly? Apart from a few gustatory chemoreceptors. the only proteins that have so far been suggested as possible glucose sensors are two glucose transporter homologues found in yeast, both of which transduce the external glucose signal to control gene expression in the cell. However, little else was known about these sensor proteins until scientists from Los Angeles and Wurzburg recently discovered a novel human glucose sensor hiding in a large family of Na~+/glucose cotransporters called SLC5.