摘要
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 poptide 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 re-stricted to heteretrephic tissues. These results suggest that glucose 6-phosphate imported via GPT can be used for starch biosynthesis in rice nongreen
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.
