A Quadruple Mutant of OsPRP1 Controls Pollen Fertility by Regulating the Expression of Anther Development-Related Genes in Oryza sativa L.

Abstract

Plant proline-rich proteins (PRPs) are cell wall proteins that are widely distributed in plants. Previous studies have shown that these proteins play a crucial role in adversity stress processes, but their function in the regulation of pollen fertility in rice remains unknown. In this study, we identified that OsPRP1 contains a Pollen_Ole-e_I allergenic structural domain, obtained the OsPRP1 quadruple mutant named osprp1.1/1.2/1.3/1.4, and observed significant reductions in pollen fertility, seed-setting rates, and the deformation and collapse of microspores during the late stages of pollen development. RNA-Seq analysis indicated the down-regulation of genes involved in anther development in osprp1.1/1.2/1.3/1.4, suggesting that OsPRP1 plays a role in regulating pollen fertility. In conclusion, a loss of function in OsPRP1.1/1.2/1.3/1.4 leads to decreased pollen fertility and seeding rates, which not only expands the functional spectrum of plant PRP genes but also provides new theoretical insight into the mechanism of fertility regulation in rice.