Heterotrimeric G proteins regulate nitrogen-use efficiency in rice.

Sun, H; Qian, Q; Wu, K; Luo, J; Wang, S; Zhang, C; Ma, Y; Liu, Q; Huang, X; Yuan, Q; Han, R; Zhao, M; Dong, G; Guo, L; Zhu, X; Gou, Z; Wang, W; Wu, Y; Lin, H; Fu, X

Nature genetics 2014 6

PMID: 24777451

Heterotrimeric G proteins regulate nitrogen-use efficiency in rice.

The drive toward more sustainable agriculture has raised the profile of crop plant nutrient-use efficiency. Here we show that a major rice nitrogen-use efficiency quantitative trait locus (qNGR9) is synonymous with the previously identified gene >DEP1 (DENSE AND ERECT PANICLES 1). The different DEP1 alleles confer different nitrogen responses, and genetic diversity analysis suggests that DEP1 has been subjected to artificial selection during Oryza sativa spp. japonica rice domestication. The plants carrying the dominant dep1-1 allele exhibit nitrogen-insensitive vegetative growm-5412'>>th coupled with increased nitrogen uptake and assimilation, resulting in improved harvest index and grain yield at moderate levels of nitrogen fertilization. The DEP1 protein interacts in vivo with both the Gα (RGA1) and Gβ (RGB1) subunits, and reduced RGA1 or enhanced RGB1 activity inhibits nitrogen responses. We conclude that the plant G protein complex regulates nitrogen signaling and modulation of heterotrimeric G protein activity provides a strategy for environmentally sustainable increases in rice grain yield.