Defective Kernel 39 encodes a PPR protein required for seed development in maize

• Published in: Journal of integrative plant biology 2018, Vol.60 (1), p.45-64
• Main Authors: Li, Xiaojie, Gu, Wei, Sun, Silong, Chen, Zongliang, Chen, Jing, Song, Weibin, Zhao, Haiming, Lai, Jinsheng
• Format: Article
• Language: English
• Subjects: Amino acid sequence; Amino acids; Arabidopsis; Base Sequence; Chloroplasts; Chloroplasts - metabolism; Cloning; Cloning, Molecular; Corn; Editing; Electron transport chain; Electron Transport Complex I - metabolism; Embryogenesis; Embryonic growth stage; Endosperm; Endosperm - embryology; Endosperm - genetics; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; Genetic Complementation Test; Homology; Lethality; Mitochondria; Mitochondria - metabolism; Mutation - genetics; NADH; NADH dehydrogenase; Nicotinamide adenine dinucleotide; Phenotype; Plant Proteins - genetics; Plant Proteins - metabolism; Plastids; Post-transcription; Protein Transport; Proteins; Ribonucleic acid; RNA; RNA editing; RNA Editing - genetics; Seedlings; Seedlings - anatomy & histology; Seeds - embryology; Seeds - metabolism; Subcellular Fractions - metabolism; Transformation, Genetic; Zea mays - embryology; Zea mays - genetics; Zea mays - metabolism; 植物; 科学研究
• ISSN: 1672-9072; 1744-7909
• DOI: 10.1111/jipb.12602

RNA editing is a posttranscriptional processthat is important in mitochondria and plastids of higherplants. All RNA editing-specific trans-factors reported sofar belong to PLS-class of pentatricopeptide repeat （PPR）proteins. Here, we report the map-based cloning andmolecular characterization of a defective kernel mutantdek39 in maize. Loss of Dek39 function leads to delayedembryogenesis and endosperm development, reducedkernel size, and seedling lethality. Dek39 encodes an E sub-class PPR protein that targets to both mitochondria andchloroplasts, and is involved in RNA editing in mitochon-drial NADH dehydrogenase3 （had3） at nad3-247 and had3-275. C-to-U editing of had3-275 is not conserved and evenlost in Arabidopsis, consistent with the idea that no closeDEK39 homologs are present in Arabidopsis. However, theamino acids generated by editing nad3-247 and nad3-275are highly conserved in many other plant species, and thereductions of editing at these two sites decrease theactivity of mitochondria NADH dehydrogenase complex I,indicating that the alteration of amino acid sequence isnecessary for Nad3 function. Our results indicate thatDek39 encodes an E sub-class PPR protein that is involvedin RNA editing of multiple sites and is necessary for seeddevelopment of maize.