Department of Botany, Molecular Ecology Laboratory, Faculty of Science, Hamdard University, New Delhi 110062, India.
Appl Biochem Biotechnol. 2012 Oct;168(4):834-50. doi: 10.1007/s12010-012-9823-4. Epub 2012 Aug 18.
Nitrogen (N) is an essential nutrient for plants. Increase in crop production is associated with increase in N fertilizers. Excessive use of N fertilizers and the low nitrogen utilization efficiency by crop plants is a major cause for environmental damage. Therefore, to reduce the N-fertilizer pollution, there is an urgent need to improve nitrogen use efficiency. Identification and/or development of genotypes which can grow and yield well at low nitrogen levels may provide a solution. Understanding the molecular mechanism of differential nitrogen use efficiency of the genotypes may provide some clues. Keeping the above facts in mind, in this study we have identified the high N-responsive and low N-responsive contrasting rice genotypes, out of 20 genotypes that were grown at low (1 mM), moderate (10 mM), and high (25 mM) levels of N (KNO(3)). Proteome analysis of leaves revealed that the proteins involved in the energy production/regulation and metabolism in plant leaf tissues are differentially expressed under N treatments. Moreover, some disease-resistant and stress-induced proteins were found to be overexpressed at high levels of N. The present study could be useful in identifying proteins responding to different levels of nitrogen fertilization, which may open new avenues for a better understanding of N use efficiency, and for developing new strategies to enhance N efficiency in cereal crops.
氮（N）是植物必需的营养物质。作物产量的增加与氮肥的增加有关。过量使用氮肥和作物对氮的利用率低是造成环境破坏的主要原因。因此，为了减少氮肥污染，迫切需要提高氮素利用效率。鉴定和/或开发能够在低氮水平下生长和高产的基因型可能是一种解决方案。了解基因型氮利用效率差异的分子机制可能提供一些线索。考虑到上述事实，在这项研究中，我们从 20 种在低（1 mM）、中（10 mM）和高（25 mM）氮水平（KNO3）下生长的基因型中，鉴定出了高氮响应和低氮响应的对照水稻基因型。叶片的蛋白质组分析表明，在氮处理下，参与植物叶片组织能量产生/调节和代谢的蛋白质表达水平不同。此外，还发现一些抗病和应激诱导的蛋白质在高氮水平下过表达。本研究有助于鉴定对不同氮施肥水平有反应的蛋白质，这可能为更好地理解氮利用效率以及开发提高谷类作物氮效率的新策略开辟新途径。
