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PubMed · 12804577

Sugars regulate sucrose transporter gene expression in citrus.

Chun Yao Li·Jian Xin Shi·David Weiss·Eliezer E Goldschmidt
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Abstract

We report the isolation and characterization of two sucrose transporter cDNAs (CitSUT1 and CitSUT2) from citrus. CitSUT1 and CitSUT2 encode putative proteins (CitSUT1 and CitSUT2) of 528 and 607 amino acids, respectively. CitSUT1 and CitSUT2 share high similarities with sucrose transporters isolated from other plants. The expression of CitSUT1 in mature leaf discs is repressed by exogenous sucrose, glucose, mannose, and the glucose analog 2-deoxyglucose but not by another glucose analog 3-O-methylglucose, indicating a hexokinase (HXK)-mediated signaling pathway. CitSUT2 expression is not affected by exogenous sugars. Whereas CitSUT1 expresses strongly in source, sugar exporting organs, CitSUT2 expresses more strongly in sink, sugar importing organs, suggesting different physiological roles for these sucrose transporters.

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Amino Acid SequenceAmino AcidsBiological TransportBlotting, NorthernBlotting, SouthernCarbohydrate MetabolismDNADNA, ComplementaryDeoxyglucoseFruitGlucoseHexokinaseMannoseMembrane Transport ProteinsMolecular Sequence DataPhylogenyPlant BarkPlant LeavesPlant ProteinsPlant RootsRNASequence Homology, Amino AcidSignal TransductionSucroseTime FactorsTreesJournal ArticleResearch Support, Non-U.S. Gov't

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Chun Yao Li, Jian Xin Shi, David Weiss, Eliezer E Goldschmidt. 2003-06-27. Sugars regulate sucrose transporter gene expression in citrus.. https://doi.org/10.1016/s0006-291x(03)00978-1

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