Phytic acid is the major source of phosphorus and other mineral bound compounds in many plant tissues especially seeds and bran of cereals. During germination, phytase enzyme degrades phytic acid and bound phosphate and minerals are released. The monogastric animal cannot digest phytate due to lack of the phytase enzyme. Considering that, we have generated low phytate rice by over expressing appA gene cloned from E. coli under the aleurone-specific promoter of maize zein gene. Molecular analysis confirmed the stable integration of transgene and plants were grown up to T₃ generation. The T₃ seeds showed around 45% decrease in seed phytate content with a fourfold increase of inorganic phosphorus (Pi) level. The enhanced iron and zinc was twofold and threefold respectively in polished seeds of transgenic plants. There was no change in germination behaviour and other morphological traits in transgenic seeds. Thus, this result provides evidence that tissue-specific expression of bacterial phytase can lead to the reduction of phytic acid in rice seeds without hampering its other physiological processes and phenotypic cost.

中文翻译：

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带有appA基因的转基因水稻增强了磷和矿物质

植酸是许多植物组织（尤其是谷物的种子和麸皮）中磷和其他与矿物结合的化合物的主要来源。在发芽过程中，肌醇六磷酸酶降解肌醇六磷酸，结合的磷酸盐和矿物质被释放。由于缺乏肌醇六磷酸酶，单胃动物无法消化肌醇六磷酸。考虑到这一点，我们通过在玉米醇溶蛋白基因的糊粉特异性启动子下过表达从大肠杆菌克隆的appA基因来产生低植酸水稻。分子分析证实了转基因的稳定整合，并且植物可以长到T ₃代。T ₃种子的植酸含量降低了约45％，而无机磷（Pi）含量则提高了四倍。在转基因植物的抛光种子中，增强的铁和锌分别为两倍和三倍。转基因种子的发芽行为和其他形态性状没有变化。因此，该结果提供了证据，即细菌植酸酶的组织特异性表达可以导致水稻种子中植酸的减少，而不会影响其其他生理过程和表型成本。