Yuqing He and colleagues show that Chalk5, a major quantitative trait locus for grain chalkiness in rice, encodes a vacuolar pyrophosphatase with H+ translocation activity. They find that elevated expression of Chalk5 disturbs the endomembrane trafficking system in developing seeds, leading to an accumulation of vesicle-like structures and increased chalkiness.
- Yibo Li
- Chuchuan Fan
- Yuqing He
