Pre-harvest sprouting (PHS) frequently occurs in rice due to the long spells of rainy weather, and causes severe yield loss and grain quality decrease. Here, we identified one PHS-related gene OsCNX1 cloned from rice PHS mutant, which encoded a molybdenum cofactor (MoCo) biosynthesis enzyme. Genetic complementation indicated OsCNX1 could rescue the PHS and seedling lethal phenotype of the mutant. Expression pattern showed that OsCNX1 was expressed in rice tissue including seedling shoot, culm, blade, and sheath of flag leaf, young panicle, and the seeds at different development stages. Overexpression of OsCNX1 significantly decreased the plant height, and the seed germination of the dormant seeds harvested from fresh panicles, comparing to the wild type (WT). In addition, 1492 differentially expressed genes (DEGs) were identified between OsCNX1-overexpressed line and WT by RNA-sequencing, which were mainly classified in plant-pathogen interaction, plant hormone signal transduction, and starch/sucrose metabolism. These results showed that OsCNX1 was not only necessary for rice seed germination, but also participated in plant development, indicating that OsCNX1 may be useful in rice breeding of PHS resistance and plant height.

由于长时间的阴雨天气，水稻经常发生穗前发芽现象，造成严重的减产和品质下降。 在这里，我们鉴定了从水稻 PHS 突变体中克隆的一个 PHS 相关基因OsCNX1 ，该基因编码一种钼辅因子 (MoCo) 生物合成酶。遗传互补表明OsCNX1可以挽救突变体的PHS和幼苗致死表型。表达模式显示，OsCNX1在水稻组织中表达，包括苗芽、秆、叶片、旗叶鞘、幼穗以及不同发育阶段的种子。与野生型（WT）相比， OsCNX1的过表达显着降低了植物高度，并且从新鲜圆锥花序收获的休眠种子的种子发芽率显着降低。此外，通过RNA测序，在OsCNX1过表达系和WT之间鉴定出1492个差异表达基因（DEG），主要分为植物-病原体相互作用、植物激素信号转导和淀粉/蔗糖代谢。这些结果表明OsCNX1不仅是水稻种子萌发所必需的，而且还参与植物发育，表明OsCNX1可能有助于水稻抗PHS和株高育种。