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Plant Sugar transport protein subfamily of the Major Facilitator Superfamily of transporters The plant Sugar transport protein (STP) subfamily includes STP1-STP14; they are also called hexose transporters. They mediate the active uptake of hexoses such as glucose, 3-O-methylglucose, fructose, xylose, mannose, galactose, fucose, 2-deoxyglucose and arabinose, by sugar/hydrogen symport. Several STP family transporters are expressed in a tissue-specific manner, or at specific developmental stages. STP1 is the member with the highest expression level of all members and high expression is detected in photosynthetic tissues, such as leaves and stems, while roots, siliques, and flowers show lower expression levels. It plays a major role in the uptake and response of Arabidopsis seeds and seedlings to sugars. The STP subfamily belongs to the Glucose transporter -like (GLUT-like) family of the Major Facilitator Superfamily (MFS) of membrane transport proteins. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement. |
Jiyao W et al.(2023). "The conserved domain database in 2023.",