Rice FLOURY ENDOSPERM 18 encodes a pentatricopeptide repeat protein required for 5'processing of mitochondrial nad5 messenger RNA and endosperm development

• 来源期刊: 植物学报（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: Cell and Developmental Biology
• 页码范围: 834-847
• 页数: 14页
• 语种: 英文

摘要

Pentatricopeptide repeat (PPR) proteins,composing one of the largest protein families in plants,are involved in RNA binding and regulation of organelle RNA metabolism at the post-transcriptional level.Although several PPR proteins have been implicated in endosperm development in rice (Oryza sativa),the molecular functions of many PPRs remain obscure.Here,we identified a rice endosperm mutant named floury endosperm 18 (flo 18) with pleiotropic defects in both reproductive and vegetative development.Map-based cloning and complementation tests showed that FLO18 encodes a mitochondrion-targeted P-type PPR protein with 15 PPR motifs.Mitochondrial function was disrupted in the flo 18 mutant,as evidenced by decreased assembly of Complex I in the mitochondrial electron transport chain and altered mitochondrial morphology.Loss of FLO18 function resulted in defective 5'-end processing of mitochondrial nad5 transcripts encoding subunit 5 of nicotinamide adenine dinucleotide hydrogenase.These results suggested that FLO18 is involved in 5'-end processing of nad5 messenger RNA and plays an important role in mitochondrial function and endosperm development.