RESEARCHERS DISCOVER REGULATOR OF ENDOSPERM DEVELOPMENT IN RICE
Abnormally developed endosperm strongly affects rice appearance and grain weight. Endosperm formation is a complex process, but several factors remain largely unknown. Scientists from the China National Rice Research Institute studied a recessive mutant, wb1, in hopes of studying factors affecting endosperm development in rice.
The wb1 mutant develops a white-belly endosperm and abnormal starch granules in the inner portion of white grains. Grains of wb1 also showed higher grain chalkiness and a lower 1000-grain weight, a 34% decrease from that of wildtype grains. The contents of amylose and amylopectin in wb1 significantly decreased, and its physical properties were also altered.
The analysis identified 12 candidate genes that could be implicated for the wb1 mutant. Further analysis of transcript levels of all candidate genes showed that White Belly 1 (WB1), which encodes a cell-wall invertase, was the most probable cause of white-belly endosperm phenotype.
Switching off of WB1 using the CRISPR-Cas9 system in Nipponbare rice lines confirms that WB1 regulates endosperm development and is responsible for the wb1 mutation.
For more information, read the article in the International Journal of Molecular Sciences.