Plant Molecular Biology and Biotechnology Laboratory, Department of Botany, University of Calcutta, Kolkata, India.
GM Crops Food. 2012 Oct-Dec;3(4):310-6. doi: 10.4161/gmcr.22104. Epub 2012 Sep 19.
Rice being a staple food, contains little iron in the edible grain. To increase the iron nutrition in rice grains, our present study highlights the first time development of high iron rice grain by exploring the endosperm specific overexpression of endogenous ferritin gene. The gene has been cloned from rice and overexpressed under the control of endosperm specific GlutelinA2 (OsGluA 2) promoter. After genetic transformation of aromatic indica rice cultivar, Pusa-sugandhi II, the milled seeds of resulting T 3 transgenics exhibited 7.8-fold of ferritin overexpression, which contributed to 2.09- and 1.37-fold of iron and zinc accumulation respectively. T 3 seeds demonstrated endosperm specific localization of iron that confirms the tissue specific activity of GluA2 promoter. Transgenic and non-transgenic plants showed no difference in their agronomic traits. Our study suggested that overexpression of rice endogenous ferritin gene is a step ahead toward cisgenic approach and can act as an effective tool for iron biofortification.
大米是主食，食用谷物中的铁含量很少。为了增加大米中的铁营养，我们目前的研究首次通过探索胚乳特异性过表达内源性铁蛋白基因来开发高铁大米。该基因已从水稻中克隆，并在胚乳特异性谷蛋白 A2（OsGluA2）启动子的控制下过表达。在芳香籼稻品种 Pusa-sugandhi II 进行遗传转化后，T3 转基因后代的碾磨种子中铁蛋白的表达量增加了 7.8 倍，导致铁和锌的积累分别增加了 2.09 倍和 1.37 倍。T3 种子显示铁的胚乳特异性定位，这证实了 GluA2 启动子的组织特异性活性。转基因和非转基因植物在农艺性状上没有差异。我们的研究表明，水稻内源铁蛋白基因的过表达是向顺式基因方法迈进的一步，可以作为铁生物强化的有效工具。
