Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Sciences, South China Normal University, Guangzhou, 510631, China.
School of Pharmaceutical Sciences, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China.
BMC Plant Biol. 2023 Oct 5;23(1):465. doi: 10.1186/s12870-023-04445-y.
The P-stalk is a conserved and vital structural element of ribosome. The eukaryotic P-stalk exists as a P0-(P1-P2) pentameric complex, in which P0 function as a base structure for incorporating the stalk onto 60S pre-ribosome. Prior studies have suggested that P0 genes are indispensable for survival in yeast and animals. However, the functions of P0 genes in plants remain elusive.
In the present study, we show that rice has three P0 genes predicted to encode highly conserved proteins OsP0A, OsP0B and OsP0C. All of these P0 proteins were localized both in cytoplasm and nucleus, and all interacted with OsP1. Intriguingly, the transcripts of OsP0A presented more than 90% of the total P0 transcripts. Moreover, knockout of OsP0A led to embryo lethality, while single or double knockout of OsP0B and OsP0C did not show any visible defects in rice. The genomic DNA of OsP0A could well complement the lethal phenotypes of osp0a mutant. Finally, sequence and syntenic analyses revealed that OsP0C evolved from OsP0A, and that duplication of genomic fragment harboring OsP0C further gave birth to OsP0B, and both of these duplication events might happen prior to the differentiation of indica and japonica subspecies in rice ancestor.
These data suggested that OsP0A functions as the predominant P0 gene, playing an essential role in embryo development in rice. Our findings highlighted the importance of P0 genes in plant development.
P stalk 是核糖体保守且至关重要的结构元件。真核生物 P stalk 作为一个 P0-（P1-P2）五聚体复合物存在，其中 P0 作为将 stalk 结合到 60S 前核糖体的基本结构发挥作用。先前的研究表明，P0 基因对酵母和动物的生存是不可或缺的。然而，P0 基因在植物中的功能仍不清楚。
在本研究中，我们表明水稻有三个 P0 基因，预测编码高度保守的蛋白质 OsP0A、OsP0B 和 OsP0C。所有这些 P0 蛋白都定位于细胞质和细胞核中，并且都与 OsP1 相互作用。有趣的是，OsP0A 的转录本占 P0 总转录本的 90%以上。此外，OsP0A 的敲除导致胚胎致死，而 OsP0B 和 OsP0C 的单敲除或双敲除在水稻中没有显示任何明显的缺陷。OsP0A 的基因组 DNA可以很好地互补 osp0a 突变体的致死表型。最后，序列和共线性分析表明，OsP0C 是由 OsP0A 进化而来的，而含有 OsP0C 的基因组片段的重复进一步产生了 OsP0B，这两个重复事件可能发生在水稻祖先的籼稻和粳稻亚种分化之前。
这些数据表明，OsP0A 作为主要的 P0 基因发挥作用，在水稻胚胎发育中起着至关重要的作用。我们的研究结果强调了 P0 基因在植物发育中的重要性。
