Journal of Zhejiang University SCIENCE
(ISSN 1009-3095, Monthly)

2003   Vol. 4   No. 3   p.331-335


Cloning and characterization of a glucose 6-phosphate/phosphate translocator from Oryza sativa

JIANG Hua-wu(½ª»ªÎä)(The State Key Laboratory of Plant Physiology and Biochemistry, College of Life sciences, Zhejiang University, Hangzhou 310029, China)
DIAN Wei-min(µèεÃô)(The State Key Laboratory of Plant Physiology and Biochemistry, College of Life sciences, Zhejiang University, Hangzhou 310029, China)
LIU Fei-yan(Áõ·ÇÑà)(The State Key Laboratory of Plant Physiology and Biochemistry, College of Life sciences, Zhejiang University, Hangzhou 310029, China)
WU Ping(ÎâÆ½)(The State Key Laboratory of Plant Physiology and Biochemistry, College of Life sciences, Zhejiang University, Hangzhou 310029, China)

Abstract:Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6-phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6-phosphate/phosphate translocator (GPT) was isolated from a cDNA library of immature seeds of rice and named as OsGPT. The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000-grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6-phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids.
Keywords:Glucose 6-phosphate/phosphate translocator, Starch synthesis, Rice (Oryza sativa L.)

CLC Number:Q943.2 Document ID:A

Foundation Item:Project supported by National Natural Science Foundation of China(No.39830250) and Natural Science Foundation of Zhejiang Province(No.2A0106), China. The nucleotide sequence data will appear in the GenBank under accession number AF375053.
Author Resume:WU Ping,E-mail: docpwu@cls.zju.edu.cn

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Manuscript Received:2002 June 26

Manuscript Revised:2002 Sept. 6

Published:2003 June 1