植物谷氨酰胺合成酶研究进展及其应用前景

Progress and application prospects of glutamine synthase in plants

摘要:

氮素是制约作物产量的主要营养元素之一，谷氨酰胺合成酶 (Glutamine synthase, GS; EC 6.3.1.2) 是氮素代谢途径中的关键酶。目前，拟南芥、水稻、小麦和玉米等植物中的GS成员均已被分离鉴定。研究表明，超表达GS能够提高植物对氮素的利用效率，从而在植株的生长发育特别是产量形成过程中发挥重要作用，但是其功能在不同植物上并不完全一致，可能与GS基因受到转录和翻译后等水平的调控有关。以下综述了植物GS基因分类、QTL定位、对氮素代谢响应、组织表达特异性、生物学功能及其分子调控机制等方面的研究进展，并展望了植物GS基因的应用前景，以期为利用GS基因来提高植物氮素利用效率提供具有参考价值的信息。

Abstract:

Nitrogen is one of the most important nutrient elements for plants and a major limiting factor in plant growth and crop productivity. Glutamine synthase (GS) is a key enzyme involved in the nitrogen assimilation and recycling in plants. So far, members of the glutamine synthase gene family have been characterized in many plants such as Arabidopsis, rice, wheat, and maize. Reports show that GS are involved in the growth and development of plants, in particular its role in seed production. However, the outcome has generally been inconsistent, which are probably derived from the transcriptional and post-translational regulation of GS genes. In this review, we outlined studies on GS gene classification, QTL mapping, the relationship between GS genes and plant growth with nitrogen and the distribution characters, the biological functions of GS genes, as well as expression control at different regulation levels. In addition, we summarized the application prospects of glutamine synthetase genes in enhancing plant growth and yield by improving the nitrogen use efficiency. The prospects were presented on the improvement of nitrogen utility efficiency in crops and plant nitrogen status diagnosis on the basis of glutamine synthase gene regulation.