bims-plasge 2022-02-27 papers

Plant Physiol. 2022 Feb 26. pii: kiac086. [Epub ahead of print]

Pentatricopeptide repeat protein CNS1 regulates maize mitochondrial complex III assembly and seed development.

Shuai Ma, Wenzhu Yang, Xiaoqing Liu, Suzhen Li, Ye Li, Jiameng Zhu, Chunyi Zhang, Xiaoduo Lu, Xiaojin Zhou, Rumei Chen.

Mitochondrial function relies on the assembly of electron transport chain complexes, which requires coordination between proteins encoded by the mitochondrion and those of the nucleus. Here, we cloned a maize (Zea mays) cytochrome c maturation FN stabilizer1 (CNS1) and found it encodes a pentatricopeptide repeat (PPR) protein. Members of the PPR family are widely distributed in plants and are associated with RNA metabolism in organelles. P-type PPR proteins play essential roles in stabilizing the 3'-end of RNA in mitochondria; whether a similar process exists for stabilizing the 5' terminus of mitochondrial RNA remains unclear. The kernels of cns1 exhibited arrested embryo and endosperm development, whereas neither conventional splicing deficiency nor RNA editing difference in mitochondrial genes was observed. Instead, most of the ccmFN transcripts isolated from cns1 mutant plants were 5'-truncated and therefore lacked the start codon. Biochemical and molecular data demonstrated that CNS1 is a P-type PPR protein encoded by nuclear DNA and that it localizes to the mitochondrion. Also, one binding site of CNS1 located upstream of the start codon in the ccmFN transcript. Moreover, abnormal mitochondrial morphology and dramatic upregulation of alternative oxidase genes were observed in the mutant. Together, these results indicate that CNS1 is essential for reaching a suitable level of intact ccmFN transcripts through binding to the 5'-UTR of the RNAs and maintaining 5'-integrity, which is crucial for sustaining mitochondrial complex III function to ensure mitochondrial biogenesis and seed development in maize.

Keywords: ccmFN ; defective kernel ; PPR; complex III; mitochondrion; seed development

DOI: https://doi.org/10.1093/plphys/kiac086

Theor Appl Genet. 2022 Feb 22.

A major-effect genetic locus, ApRVII, controlling resistance against both adapted and non-adapted aphid biotypes in pea.

Rémi Ollivier, Isabelle Glory, Romuald Cloteau, Jean-François Le Gallic, Gaëtan Denis, Stéphanie Morlière, Henri Miteul, Jean-Philippe Rivière, Angélique Lesné, Anthony Klein, Grégoire Aubert, Jonathan Kreplak, Judith Burstin, Marie-Laure Pilet-Nayel, Jean-Christophe Simon, Akiko Sugio.

KEY MESSAGE: A genome-wide association study for pea resistance against a pea-adapted biotype and a non-adapted biotype of the aphid, Acyrthosiphon pisum, identified a genomic region conferring resistance to both biotypes. In a context of reduced insecticide use, the development of cultivars resistant to insect pests is crucial for an integrated pest management. Pea (Pisum sativum) is a crop of major importance among cultivated legumes, for the supply of dietary proteins and nitrogen in low-input cropping systems. However, yields of the pea crop have become unstable due to plant parasites. The pea aphid (Acyrthosiphon pisum) is an insect pest species forming a complex of biotypes, each one adapted to feed on one or a few related legume species. This study aimed to identify resistance to A. pisum and the underlying genetic determinism by examining a collection of 240 pea genotypes. The collection was screened against a pea-adapted biotype and a non-adapted biotype of A. pisum to characterize their resistant phenotype. Partial resistance was observed in some pea genotypes exposed to the pea-adapted biotype. Many pea genotypes were completely resistant to non-adapted biotype, but some exhibited partial susceptibility. A genome-wide association study, using pea exome-capture sequencing data, enabled the identification of the major-effect quantitative trait locus ApRVII on the chromosome 7. ApRVII includes linkage disequilibrium blocks significantly associated with resistance to one or both of the two aphid biotypes studied. Finally, we identified candidate genes underlying ApRVII that are potentially involved in plant-aphid interactions and marker haplotypes linked with aphid resistance. This study sets the ground for the functional characterization of molecular pathways involved in pea defence to the aphids but also is a step forward for breeding aphid-resistant cultivars.

DOI: https://doi.org/10.1007/s00122-022-04050-x

Genes (Basel). 2022 Jan 22. pii: 196. [Epub ahead of print]13(2):

An Integrated Linkage Map of Three Recombinant Inbred Populations of Pea (Pisum sativum L.).

Chie Sawada, Carol Moreau, Gabriel H J Robinson, Burkhard Steuernagel, Luzie U Wingen, Jitender Cheema, Ellen Sizer-Coverdale, David Lloyd, Claire Domoney, Noel Ellis.

Biparental recombinant inbred line (RIL) populations are sets of genetically stable lines and have a simple population structure that facilitates the dissection of the genetics of interesting traits. On the other hand, populations derived from multiparent intercrosses combine both greater diversity and higher numbers of recombination events than RILs. Here, we describe a simple population structure: a three-way recombinant inbred population combination. This structure was easy to produce and was a compromise between biparental and multiparent populations. We show that this structure had advantages when analyzing cultivar crosses, and could achieve a mapping resolution of a few genes.

Keywords: genetic map; integrated map; pea; recombinant inbred population

DOI: https://doi.org/10.3390/genes13020196

Genes (Basel). 2022 Feb 08. pii: 316. [Epub ahead of print]13(2):

Gene-Based Resistance to Erysiphe Species Causing Powdery Mildew Disease in Peas (Pisum sativum L.).

Jyoti Devi, Gyan P Mishra, Vidya Sagar, Vineet Kaswan, Rakesh K Dubey, Prabhakar M Singh, Shyam K Sharma, Tusar K Behera.

Globally powdery mildew (PM) is one of the major diseases of the pea caused by Erysiphe pisi. Besides, two other species viz. Erysiphe trifolii and Erysiphe baeumleri have also been identified to infect the pea plant. To date, three resistant genes, namely er1, er2 and Er3 located on linkage groups VI, III and IV respectively were identified. Studies have shown the er1 gene to be a Pisum sativum Mildew resistance Locus 'O' homologue and subsequent analysis has identified eleven alleles namely er1-1 to er1-11. Despite reports mentioning the breakdown of er1 gene-mediated PM resistance by E. pisi and E. trifolii, it is still the most widely deployed gene in PM resistance breeding programmes across the world. Several linked DNA markers have been reported in different mapping populations with varying linkage distances and effectiveness, which were used by breeders to develop PM-resistant pea cultivars through marker assisted selection. This review summarizes the genetics of PM resistance and its mechanism, allelic variations of the er gene, marker linkage and future strategies to exploit this information for targeted PM resistance breeding in Pisum.

Keywords: Erysiphe; Pisum; er gene; marker-assisted selection; powdery mildew

DOI: https://doi.org/10.3390/genes13020316