en.Wedoany.com Reported - An innovative team led by Academician Wan Jianmin from the Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, in collaboration with Nanjing Agricultural University, has cloned and elucidated the molecular mechanism by which a key gene regulating rice storage protein transport maintains cellular calcium ion homeostasis, thereby ensuring the transport and accumulation of rice storage proteins. The findings were published in The Plant Cell.

As the second most abundant nutrient in rice, protein content and composition directly affect the taste, nutrition, and functional quality of rice. Previous studies have identified the core protein complex involved in protein transport, but the upstream regulatory mechanism remains unclear.

The research team screened and identified a mutant with abnormal glutelin accumulation and cloned its target gene. The study found that mutation of this gene causes glutelin, which should normally be stored inside seed cells, to become "lost" and be erroneously secreted outside the cells. Further investigation revealed that calcium ions act as "traffic controllers" within cells, and this gene specifically maintains the number of these "traffic controllers" on organelles, thereby recruiting the core protein complex required for organelle transport and ensuring efficient glutelin transport along the designated intracellular route. Additionally, this gene works synergistically with its homologous gene to maintain the stability and efficiency of glutelin transport in rice. This study provides new insights and important targets for the genetic improvement of rice protein quality.

This research was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, and the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences.