Journal Article

A G-protein pathway determines grain size in rice

Xiao, Jinghua, Shao, Lin, Sun, Shengyuan, Ouyang, Yidan, Wang, Lei, Mao, Hailiang, Li, Xianghua, Zhang, Qifa

2018

Overview

Manipulating grain size is an effective strategy for increasing cereal yields. Here we identify a pathway composed of five subunits of the heterotrimeric G proteins that regulate grain length in rice. The Gβ protein is essential for plant survival and growth. Gα provides a foundation for grain size expansion. Three Gγ proteins, DEP1, GGC2 and GS3, antagonistically regulate grain size. DEP1 and GGC2, individually or in combination, increase grain length when in complex with Gβ. GS3, having no effect on grain size by itself, reduces grain length by competitively interacting with Gβ. By combining different G-protein variants, we can decrease grain length by up to 35% or increase it by up to 19%, which leads to over 40% decreasing to 28% increasing of grain weight. The wide existence of such a conserved system among angiosperms suggests a possible general predictable approach to manipulating grain/organ sizes. Grain size is a major determinant of cereal yield. Here the authors characterize five subunits of the rice heterotrimeric G proteins and find that manipulating the three Gγ proteins can achieve designed grain size, which provides a predictable approach to improving grain yield and quality.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 13/44 / 13/89 / 38/39 / 38/77 / 38/88 / 38/90 / 631/208/8 / 631/449/1870 / 631/449/711 / 82/1 / Angiosperms / Grain size / Humanities and Social Sciences / multidisciplinary / Oryza / Particle size / Proteins / Rice / Science / Science (multidisciplinary)