氮代谢直接影响植物生长发育。提高作物氮素利用率是增加产量、改善生态环境的有效措施。青稞是青藏高原特色农作物，具有很强的环境适应性。最新研究显示青稞具有高的氮素利用效率从而耐低氮胁迫。磷酸戊糖途径可为氮同化提供还原力，进而参与氮代谢过程，但分子机制仍不清楚。本项目旨在探明磷酸戊糖途径的关键酶葡萄糖-6-磷酸脱氢酶（G6PDH）在青稞氮代谢中的生理功能与分子机制。主要研究内容包括：克隆青稞G6PDH基因、确定表达模式；揭示青稞G6PDH响应氮代谢的功能、调节与信号转导机制；查明调控G6PDH响应低氮胁迫的转录因子及互作蛋白；完善青稞遗传转化体系，筛选G6PDH缺失与超表达株系；利用转录组与蛋白组技术，挖掘参与青稞氮素高效利用的新功能基因。该研究是首次系统探讨G6PDH在青稞氮代谢中的功能与调节机制，有助于阐释青稞适应高原环境的分子机制，可为提高作物氮利用率与可持续农业发展提供理论依据。

Nitrogen metabolism directly affects the growth and development of plants. The enhancement of nitrogen use efficiency in crops is an effective measure for increasing yield and improving ecological environments. Highland barley is a typical crop in the Qinghai-Tibet Plateau region, and has higher adaptability to environmental stresses than plants growing in low altitude regions. Latest research showed that highland barley has high nitrogen utilization efficiency and is able to tolerate the low nitrogen stress. The pentose phosphate pathway provides reducing power for nitrogen assimilation, thus, it participates in the process of nitrogen metabolism in plants. However, the molecular mechanism is still unclear. In this project, we will focus on deciphering the physiological function and molecular mechanism of glucose-6-phosephate dehydrogenase (G6PDH, a key enzyme of pentose phosphate pathway), in the tolerance of highland barley to low nitrogen. The main research goals include: cloning highland barley G6PDH genes; studying their expression profiles; investigating the function, regulatory mechanism and signal transduction mechanism of G6PDH; searching for the transcription factors and interacting proteins that regulate the response of G6PDH to low nitrogen stress; improving the genetic transformation system of highland barley, and expecting to obtain G6PDH knockdown and overexpression lines; exploring new functional genes involved in the efficient utilization of nitrogen in highland barley via transcriptome and proteome analysis. For the first time, we will explore the action and molecular mechanism of G6PDH in nitrogen metabolism of highland barley. Completion of this project will contribute to understanding the mechanism of highland barley adaptation to plateau environments and will provide the theoretical basis and guidance for improving the nitrogen use efficiency in crops and sustainable agriculture.