bims-plasge Biomed News
on Plastid genes
Issue of 2020‒07‒26
one paper selected by
Vera S. Bogdanova
Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences

  1. J Exp Bot. 2020 Jul 25. pii: eraa348. [Epub ahead of print]
      Pentatricopeptide repeat (PPR) proteins were identified as site-specific recognition factors for RNA editing in plant mitochondria and plastids. In this study, we characterized maize (Zea mays) kernel mutant defective kernel 46 (dek46), which has lethal embryo and collapsed endosperm. Dek46 encodes an E-subgroup PPR protein which possesses a short PLS repeat region of only seven repeats. Subcellular localization analysis indicated that DEK46 is localized in mitochondrion. The strand- and transcript-specific RNA-seq (STS-PCRseq) analysis showed that the dek46 mutation impacted C-to-U RNA editing at over 60 mitochondrial C targets. Biochemical analysis of mitochondrial protein complexes revealed significant reduced assembly of mitochondrial complex III in dek46. Transmission electron microscopy (TEM) observation showed severe morphological defects of mitochondria in dek46 endosperm cells. In addition, Yeast two-hybrid (Y2H) and luciferase complementation image (LCI) assays indicated that DEK46 can interact with mitochondria-targeting non-PPR RNA editing factor, ZmMORF1, suggesting that DEK46 might be a functional component in organellar RNA editosome.
    Keywords:  Dek46; RNA editing; Zea mays; ZmMORFs; editosome; mitochondria; pentatricopeptide repeat protein; seed development