Academia Sinica

Liang-Jwu Chen

Su-May Yu

Shuen-Fang Lo

Tuan-Hua David Ho

The present invention relates to mutant gibberellin 2-oxidase (GA2ox) genes and uses thereof. In particular, the effective mutations disclosed herein can reduce GA2ox enzymatic activity to different extents, leading to various degrees of GA deficient yet beneficial agronomic traits in transgenic plants.

Mutant gibberellin 2-oxidase genes and uses thereof

Novel gibberellin 2-oxidase (GA2ox) genes were identified. Differential expression of GA2ox genes correlated with flower development, seed germination, tiller growth and other developmental processes. In addition, the early and increased growth of tiller and adventitious root and altered root architecture caused by overexpression of GA2oxs further suggest the pleiotropic role of GA2oxs in controlling growth and architecture in plants such as rice. GA2ox5, GA2ox6 and GA2ox9 were three genes encoding class C20 GA2oxs in rice. Mutants or transgenic rice overexpressing class C20 GA2oxs exhibited a broad range of mutant phenotypes, including semi-dwarfism, increased root system and higher tiller numbers that may favor grain yield. Mutations in the conserved domain III were found to affect the physiological activity of class C20 GA2oxs. Methods are described for controlling plant growth and architecture by controlling gene expression of gibberellin 2-oxidase in the plant.

Method of controlling plant growth and architecture by controlling expression of gibberellin 2-oxidase

Novel gibberellin 2-oxidase (GA2ox) genes were identified. Differential expression of GA2ox genes correlated with flower development, seed germination, tiller growth and other developmental processes. In addition, the early and increased growth of tiller and adventitious root and altered root architecture caused by overexpression of GA2oxs further suggest the pleiotropic role of GA2oxs in controlling growth and architecture in plants such as rice. GA2ox5, GA2ox6 and GA2ox9 were three genes encoding class C20 GA2oxs in rice. Mutants or transgenic rice overexpressing class C20 GA2oxs exhibited a broad range of mutant phenotypes, including semi-dwarfism, increased root system and higher tiller numbers that may favor grain yield. Mutations in the conserved domain III were found to affect the physiological activity of class C20 GA2oxs.

Growing community of inventors

Taichung, Taiwan

Liang-Jwu Chen