Zhang Maoxing, Zhou Boyang, Cheng Yuan, Zhong Chunyan, Yu Min, Pan Ting, Zhu Yiyong
International Research Centre for Environmental Membrane Biology, Department of Horticulture, Foshan University, Foshan, 528000, China.
Zhaoqing Academy of Agriculture and Forestry Sciences, Zhaoqing, 526040, China.
J Plant Physiol. 2024 Dec;303:154368. doi: 10.1016/j.jplph.2024.154368. Epub 2024 Oct 3.
Utilization of nitrogen by crops is essential for sustainable agriculture. The transport of nitrate (NO) across the plasma membrane is a critical gateway for N uptake and subsequent utilization. This process requires proton (H) coupled cotransport, which is driven by proton motive force, provided by plasma membrane (PM) H-ATPase. In this report, two indica rice varieties [Meixiangzhan 2 (MXZ) and Jifengyou 1002 (JFY)] in South China were selected and cultivated in hydroponic solution with 0.5 mM or 2.0 mM NO as the N source. The JFY exhibited stronger growth with higher biomass than MXZ under both 0.5 mM and 2.0 mM NO. PM H-ATPase activity of JFY roots was significantly higher than that of MXZ. The higher PM H-ATPase activity in JFY was consistent with a higher abundance of PM H-ATPase protein and higher transcription levels of OSAs, such as OSA2, OSA7 and OSA8 in roots, OSA3, OSA7 and OSA8 in leaves. The expression of nitrate transporters (OsNRT1;1b, OsNRT2.1, OsNRT2.2, and OsNAR2.1) were also higher in roots or shoots of JFY than those in MXZ. Under 0.5 mM and 2.0 mM NO, the NO absorption and translocation rate, nitrate content, as well as nitrate reductase (NR) activity were all significantly higher in JFY, as compared to those in MXZ. Taken together, in JFY and MXZ, a higher level of PM H-ATPase protein and higher activity coupled with greater efficiency in nitrate uptake, translocation and assimilation, suggesting the existence of a close correlation between PM H-ATPase and nitrate utilization in indica rice. PM H-ATPase may one of the elite genes that can contribute to nitrate use efficiency in rice.
作物对氮的利用是可持续农业的关键。硝酸盐（NO）跨质膜的转运是氮吸收及后续利用的关键途径。这一过程需要质子（H）偶联共转运，由质膜（PM）H-ATPase提供的质子动力驱动。本报告中，选取了中国南方的两个籼稻品种[美香占2号（MXZ）和吉丰优1002（JFY）]，在以0.5 mM或2.0 mM NO作为氮源的水培溶液中培养。在0.5 mM和2.0 mM NO条件下，JFY均表现出比MXZ更强的生长能力和更高的生物量。JFY根系的PM H-ATPase活性显著高于MXZ。JFY中较高的PM H-ATPase活性与PM H-ATPase蛋白的较高丰度以及根中OSA2、OSA7和OSA8、叶中OSA3、OSA7和OSA8等OSA的较高转录水平一致。JFY根或地上部中硝酸盐转运蛋白（OsNRT1;1b、OsNRT2.1、OsNRT2.2和OsNAR2.1）的表达也高于MXZ。在0.5 mM和2.0 mM NO条件下，与MXZ相比，JFY的NO吸收和转运速率、硝酸盐含量以及硝酸还原酶（NR）活性均显著更高。综上所述，在JFY和MXZ中，较高水平的PM H-ATPase蛋白和较高活性与硝酸盐吸收、转运和同化的更高效率相关，表明籼稻中PM H-ATPase与硝酸盐利用之间存在密切关联。PM H-ATPase可能是有助于提高水稻硝酸盐利用效率的优良基因之一。
