Chinese scientists uncover phosphorylation-driven auxin signaling pathway for seed size regulation in rice

In a study published in Cell Reports, Prof. Song Xianjun's group from the Institute of Botany of the Chinese Academy of Sciences has uncovered a gene network underlying the regulation of seed size in rice. The researchers found that a genetically defined cascade—OsTIR1–OsIAA10–OsARF4—plays an important role in controlling rice grain size, and Thousand-grain weight on chromosome 3 (TGW3) phosphorylation of OsIAA10 regulates the trait by altering the corresponding auxin signaling. Cultivated rice (Oryza sativa L.) is an important crop, feeding more than half the world's population. In rice, grain size is an important agronomic trait that significantly affects grain yield and quality. However, few genetically defined pathways for grain size control have been reported so far. Together with other groups, the researchers reported in 2018 a large QTL for grain size and yield, called TGW3, whose target gene encodes a ...