National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
State Key Laboratory of Plant Physiology and Biochemistry, China Agricultural University, Beijing 100193, China.
Int J Mol Sci. 2022 Mar 11;23(6):3035. doi: 10.3390/ijms23063035.
Pentatricopeptide repeat (PPR) proteins are a large protein family in higher plants and play important roles during seed development. Most reported PPR proteins function in mitochondria. However, some PPR proteins localize to more than one organelle; functional characterization of these proteins remains limited in maize ( L.). Here, we cloned and analyzed the function of a P-subfamily PPR protein, PPR278. Loss-function of led to a lower germination rate and other defects at the seedling stage, as well as smaller kernels compared to the wild type. was expressed in all investigated tissues. Furthermore, we determined that PPR278 is involved in the splicing of two mitochondrial transcripts ( intron 4 and introns 1 and 4), as well as RNA editing of C-to-U sites in 10 mitochondrial transcripts. PPR278 localized to the nucleus, implying that it may function as a transcriptional regulator during seed development. Our data indicate that PPR278 is involved in maize seed development via intron splicing and RNA editing in mitochondria and has potential regulatory roles in the nucleus.
五肽重复（PPR）蛋白是高等植物中的一个大型蛋白家族，在种子发育过程中发挥重要作用。大多数报道的 PPR 蛋白在线粒体中发挥作用。然而，一些 PPR 蛋白定位于不止一个细胞器；这些蛋白的功能特征在玉米（L.）中仍然有限。在这里，我们克隆并分析了一个 P 亚家族 PPR 蛋白 PPR278 的功能。的功能丧失导致发芽率降低和幼苗期的其他缺陷，以及与野生型相比，籽粒更小。在所有研究的组织中都有表达。此外，我们确定 PPR278 参与了两个线粒体转录物（内含子 4 和 内含子 1 和 4）的剪接，以及 10 个线粒体转录物中 C 到 U 位点的 RNA 编辑。PPR278 定位于细胞核，表明它可能在种子发育过程中作为转录调节剂发挥作用。我们的数据表明，PPR278 通过线粒体中的内含子剪接和 RNA 编辑参与玉米种子发育，并在核中有潜在的调节作用。
