Maoxing Zhang, Yin Wang, Xi Chen, Feiyun Xu, Ming Ding, Wenxiu Ye, Yuya Kawai, Yosuke Toda, Yuki Hayashi, Takamasa Suzuki, Houqing Zeng, Liang Xiao, Xin Xiao, Jin Xu, Shiwei Guo, Feng Yan, Qirong Shen, Guohua Xu, Toshinori Kinoshita & Yiyong Zhu

Nature Communications volume 12, 02 February 2021; Article number: 735 (2021) 

Nitrogen (N) and carbon (C) are essential elements for plant growth and crop yield. Thus, improved N and C utilisation contributes to agricultural productivity and reduces the need for fertilisation. In the present study, we find that overexpression of a single rice gene, Oryza sativa plasma membrane (PM) H⁺-ATPase 1 (OSA1), facilitates ammonium absorption and assimilation in roots and enhanced light-induced stomatal opening with higher photosynthesis rate in leaves. As a result, OSA1 overexpression in rice plants causes a 33% increase in grain yield and a 46% increase in N use efficiency overall. As PM H⁺-ATPase is highly conserved in plants, these findings indicate that the manipulation of PM H⁺-ATPase could cooperatively improve N and C utilisation, potentially providing a vital tool for food security and sustainable agriculture.

See: https://www.nature.com/articles/s41467-021-20964-4

Figure 1: Plasma membrane (PM) H⁺-ATPase regulates ammonium (NH₄⁺) uptake in rice.

a ¹⁵NH₄⁺ absorption rate in wild-type (WT) rice. To determine ¹⁵NH₄⁺ absorption rates, rice seedlings were incubated in 2 mM ¹⁵NH₄⁺ solution with 5 μM fusicoccin (FC) for 30 min under dark or illuminated conditions. b Average transpiration rates of rice leaves under dark and illuminated conditions over 30 min. Small circles in a, b represent data points for individual experiments; three biological replicates were analysed for each treatment. Columns and error bars in a, b represent the means ± standard errors (SEs; n = 3). Differences were evaluated using the two-tailed Student’s t test (*P < 0.05; ***P < 0.005; n.s., not significant). The exact P values are 0.0018 (mock in dark vs. FC in dark), 0.0025 (mock in dark vs. mock in light), 0.0143 (mock in light vs. FC in light) and 0.0016 (FC in dark vs. FC in light) for (a); 0.8194 (mock in dark vs. FC in dark), 0.0006 (mock in dark vs. mock in light), 0.0851 (mock in light vs. FC in light), and 4.27 × 10⁻⁵ (FC in dark vs. FC in light) for (b). n.s. Not significant.