College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China; Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, 27599-3280, USA.
College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shaanxi, China.
Plant Sci. 2018 Sep;274:129-136. doi: 10.1016/j.plantsci.2018.05.019. Epub 2018 May 24.
Nitrogen is a key nutrient for plant growth and development. Plants regulate nitrogen availability and uptake efficiency through controlling root architecture. While the heterotrimeric G protein complex is an important element to regulate root morphology, it remains unknown whether the G protein regulates the root architecture in response to nitrogen supply. We used rice and Arabidopsis G protein mutants to study the root architecture in response to different nitrogen concentrations. We found that nitrogen inhibits root horizontal projection area (network area), root perimeter, total length, but not root diameter (average root width). Nitrogen influenced bushiness and root spatial distribution by inhibiting horizontal growth and promoting vertical expansion. The dynamic changes of the rice G protein mutant DK22 at different concentrations of nitrogen from day 7 to day 9 were different from the wild type with regard to bushiness and spatial distribution. The agb1-2 mutant in Arabidopsis lacked the inhibitory effect of nitrate on root growth. The heterotrimeric G protein complex regulates the inhibitory effect on root growth caused by high nitrogen supply and root spatial distribution in response to different nitrogen concentrations.
氮是植物生长和发育的关键营养物质。植物通过控制根系结构来调节氮素的有效性和吸收效率。虽然异三聚体 G 蛋白复合物是调节根系形态的重要因素，但 G 蛋白是否调节根系结构以响应氮供应仍不清楚。我们使用水稻和拟南芥 G 蛋白突变体来研究不同氮浓度下的根系结构。我们发现，氮抑制了根的水平投影面积（网络面积）、根周长、总长度，但不抑制根直径（平均根宽）。氮通过抑制水平生长和促进垂直扩展来影响丛枝和根的空间分布。在不同氮浓度下，水稻 G 蛋白突变体 DK22 的动态变化在丛枝和空间分布方面与野生型不同。拟南芥中的 agb1-2 突变体缺乏硝酸盐对根生长的抑制作用。异三聚体 G 蛋白复合物调节高氮供应对根生长的抑制作用以及对不同氮浓度下根空间分布的调节作用。
