bims-plasge Biomed News
on Plastid genes
Issue of 2019‒03‒31
two papers selected by
Vera S. Bogdanova
Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences

  1. New Phytol. 2019 Mar 27.
      •Endosperm, the major storage organ in cereal grains, determines grain yield and quality. Despite a role for P-type PPR proteins in the regulation of endosperm development has emerged, molecular functions of many P-type PPR proteins remain obscure. •Here, we report a rice endosperm defective mutant, floury endosperm10 (flo10), which developed smaller starch grains in starchy endosperm and abnormal cells in aleurone layer. Map-based cloning and rescued experiments showed that FLO10 encodes a P-type PPR protein with 26 PPR motifs, which is localized to mitochondria. Loss function of FLO10 affected the trans-splicing of mitochondrial nad1 intron 1, which was accompanied by the increased accumulation of nad1 exon 1 and exons 2-5 precursors. •The failed formation of mature nad1 led to a dramatically decreased assembly and activity of complex I, reduced ATP production, and changed mitochondrial morphology. In addition, loss function of FLO10 significantly induced an alternative respiratory pathway involving alternative oxidase (AOXs). •These results reveal that FLO10 plays an important role in the maintenance of mitochondrial function and endosperm development through affecting the trans-splicing of mitochondrial nad1 intron 1 in rice. This article is protected by copyright. All rights reserved.
    Keywords:   nad1 ; FLO10; aleurone layer; endosperm development; intron splicing; mitochondria; pentatricopeptide repeat (PPR); rice
  2. PLoS One. 2019 ;14(3): e0214409
      Usage of high-throughput sequencing approaches allow for the generation and characterization of reference transcriptome datasets that support gene-based marker discovery, which in turn can be used to build genetic maps among other purposes. We have obtained a transcriptome assembly including 49,453 genes for the lentil (Lens culinaris Medik.) cultivar Alpo using RNAseq methodology. This transcriptome was used as reference to obtain 6,306 quality polymorphic markers (SNPs and short indels) analyzing genotype data from a RIL population at F7 generation derived from the interspecific cross between L. culinaris cv. Alpo and L. odemensis accession ILWL235. L. odemensis is a wild species included in the secondary gene pool and can be used as a source for gene introgression in lentil breeding programs. Marker data were used to construct the first genetic interspecific map between these two species. This linkage map has been used to precisely identify regions of the CDC-Redberry lentil draft genome in which the candidate genes for some qualitative traits (seed coat spotting pattern, flower color, and stem pigmentation) could be located. The genome regions corresponding to a significant single quantitative trait locus (QTL) controlling "time to flowering" located in chromosome 6 and three QTLs regulating seed size and positioned in chromosomes 1 and 5 (two QTLs) were also identified. Significant QTLs for Ascochyta blight resistance in lentil were mapped to chromosome 6 in the genome region or close to it where QTLs for Ascochyta blight resistance have previously been reported.