The main reason for the grain width difference in rice: there are differences in GSE5 gene expression.

Rice is one of the main food crops in China, and its yield is mainly determined by grain weight, spike grain and effective spike.
the size of the grain of rice affects the yield of rice.
rice breeders are using natural variations in grain size to improve rice yield and quality.
has cloned some important genes to control the size of rice grains, but the molecular mechanism of rice grain size regulation is still unclear, and only a few grain size gene alleometan variation has been widely used by breeders.
The Li Yunhai Research Group of the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences, in collaboration with the Qian Qian Research Group of the Chinese Rice Research Institute and the Ge Song Research Group of the Institute of Botany of the Chinese Academy of Sciences, carried out esoteric analysis of the size of the seeds by genome sequencing of 102 indica varieties, and located GSE5, a key quantitative location to control grain width through genome-wide analysis and gene expression analysis.
by gene expression analysis, gene knock-out and genetically modified functional complementary verification, it is proved that the expression of the difference between different rice varieties of GSE5 gene is the main reason for the difference in grain width.
study found that some indica varieties GSE5 starters have 950 base deficiencies (DEL1), most indica varieties GSE5 starters have 1.2kb missing (DEL2), DEL1 and DEL2 reduce GSE5 expression, resulting in wider grains.
of the 46.1% indica varieties, the GSE5 launcher contains DEL1 and 367 bp insertions, while the 81.3% of the indica variety GSE5 launcher contains DEL2.
the study showed that DEL1 and DEL2 in indica varieties both caused a decrease in GSE5 gene expression, resulting in an increase in grain width.
using CRISPR/Cas9 technology to remove the GSE5 gene can make the grain further widen and increase the grain weight.
, GSE5 over-expresses plant seed ethonation.
GSE5 controls the width of the seed by affecting the number of cells in the seed.
modern cultivated rice evolved from ordinary wild rice, the sequence analysis of common wild rice GSE5 in different regions shows that the different single-fold type of GSE5 in modern cultivated rice is selected from different wild rice.
This study expounds the molecular genetic basis of the grain-width difference between indica varieties and subseeds, and it is expected that the GSE5 gene can be used to improve the grain size and yield of rice, which is of great significance for high-yielding rice breeding.
The work was published online March 30 in Molecular Plant (Molecular Plant, DOI:10.1016/j.molp.2017.03.009), and Duan Penggen, an assistant researcher at Li Yunhai Research Group, and Xu Jinsong, a postdoctoral fellow, are co-authors of the paper.
the research has been funded by the Ministry of Science and Technology, the Chinese Academy of Sciences strategic pilot special, the National Natural Science Foundation of China and the National Genetically Modified Special Project.
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