Rice is an important kind of food crops worldwide, and more than half of the population in the world take rice as the food resources. The size and shape of rice grain are two key agronomic traits determining grain yield and appearance. Several genes for grain size and shape have been identified, but the molecular mechanisms underlying grain size and shape control remain largely unclear.

Arecent study by Dr. LI Yunhai’s group at the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences (CAS), in collaboration with Dr. WANG Dekai at Zhejiang Academy of Agricultural Sciences, has isolated awide and thick grain 1 (wtg1-1) mutant and has identified the WTG1 gene which regulates grain size and shape in rice. Over expression of WTG1 causes narrow, thin and long grains. Cellular analysis indicates WTG1 mainly influences cell expansion in spikelet hulls. They have found that WTG1 encodes an otubain-like protease with deubiquitination activity and shares similarity with human OTUB1. Thewtg1-1 mutant produces wide, thick, short, heavy grains and increases grain number per main panicle. These findings have revealed a new otubain-like protease WTG1 that regulates grain size and shape, and it has the potential to increase grain size and yield in rice.

This work has been published on The Plant Journal (DOI:10.1111/tpj.13613). This work was supported by grants from the Ministry of Science and Technology of China, the National Natural Science Foundation of China and the Ministry of Agriculture of China.

Source:Institute of Genetics and Developmental Biology

Time:2017.7.5