中文摘要：

把精氨酸生合成酶编码为植物的基因的特定的功能很好没被描绘。我们报导 Arabidopsis thaliana N-acetylglutamate kinase (NAGK ) 的隔离和描述，它催化精氨酸生合成的第二步。NAGK 是质体局部性的蛋白质并且在 Arabidopsis 在很发展的过程被表示。在 NAGK 缺乏的 Escherichia coli 紧张的 Arabidopsis NAGK 基因的 Heterologous 表示充分在精氨酸缺乏的媒介上恢复细菌的生长。变异的花粉试管比野类型花粉试管和显型更慢慢地种的 nagk 被也明确地恢复在花粉或精氨酸的外长的补充的互补 NAGK。nagk 女性配偶体由于那个女配偶体房间命运说明明确地被影响的事实在 micropylar 花粉试管指导是有缺点的。在 synergid 房间的 NAGK 的特定的表示救 nagk 女性配偶体的缺点。NAGK 的 Loss-of-function 导致不在四房间的胚胎阶段以外发展的 Arabidopsis 胚胎。在 nagk/NAGK 植物的胚胎有缺陷者显型不能是有精氨酸或鸟氨酸补充的救的 by watering nagk/NAGK 植物。在结论，结果在调整配偶体函数和胚胎开发揭示 NAGK 和精氨酸的一个新奇角色，并且在胚胎开发期间提供珍贵卓见进精氨酸运输(吗？植物学的 2017 研究所，中国科学院。）

英文摘要：

The specific functions of the genes encoding arginine biosynthesis enzymes in plants are not well characterized. We report the isolation and characterization of Arabidopsis thaliana N-acetylglutamate kinase （NAGK）, which catalyzes the second step of arginine biosynthesis. NAGK is a plastid-localized protein and is expressed during most developmental processes in Arabidopsis. Heterologous expression of the Arabidopsis NAGK gene in a NAGK-deficient Escherichia coli strain fully restores bacterial growth on arginine-deficient medium, nagk mutant pollen tubes grow more slowly than wild type pollen tubes and the phenotype is restored by either specifically through complementation by NAGK in pollen, or exogenous supplementation of arginine, nagk female gametophytes are defective in micropylar pollen tube guidance due to the fact that female gametophyte cell fate specification was specifically affected. Expression of NAGK in synergid cells rescues the defect of nagk female gametophytes. Loss- of-function of NAGK results in Arabidopsis embryos not developing beyond the four-celled embryo stage. The embryo-defective phenotype in nagk/NAGK plants cannot be rescued by watering nagk/NAGK plants with arginine or ornithine supplementation. In conclusion, our results reveal a novel role of NAGK and arginine in regulating gametophyte function and embryo development, and provide valuable insights into arginine transport during embryo development.