RESUMEN
The mutualistic arbuscular mycorrhizal (AM) symbiosis arose in land plants more than 450 million years ago and is still widely found in all major land plant lineages. Despite its broad taxonomic distribution, little is known about the molecular components underpinning symbiosis outside of flowering plants. The ARBUSCULAR RECEPTOR-LIKE KINASE (ARK) is required for sustaining AM symbiosis in distantly related angiosperms. Here, we demonstrate that ARK has an equivalent role in symbiosis maintenance in the bryophyte Marchantia paleacea and is part of a broad AM genetic program conserved among land plants. In addition, our comparative transcriptome analysis identified evolutionarily conserved expression patterns for several genes in the core symbiotic program required for presymbiotic signaling, intracellular colonization, and nutrient exchange. This study provides insights into the molecular pathways that consistently associate with AM symbiosis across land plants and identifies an ancestral role for ARK in governing symbiotic balance.
Asunto(s)
Embryophyta , Regulación de la Expresión Génica de las Plantas , Micorrizas , Proteínas de Plantas , Simbiosis , Simbiosis/genética , Micorrizas/fisiología , Micorrizas/genética , Embryophyta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Marchantia/genética , Marchantia/microbiología , FilogeniaRESUMEN
KEY MESSAGE: Four QTL for ergot resistance (causal pathogen Claviceps purpurea) have been identified in the durum wheat cultivar Greenshank. Claviceps purpurea is a pathogen of grasses that infects flowers, replacing the seed with an ergot sclerotium. Ergot presents a significant problem to rye, barley and wheat, in particular hybrid seed production systems. In addition, there is evidence that the highly toxic alkaloids that accumulate within sclerotia can cross-contaminate otherwise healthy grain. Host resistance to C. purpurea is rare, few resistance loci having been identified. In this study, four ergot resistance loci are located on chromosomes 1B, 2A, 5A and 5B in the durum wheat cv. Greenshank. Ergot resistance was assessed through analysis of phenotypes associated with C. purpurea infection, namely the number of inoculated flowers that produced sclerotia, or resulted in ovary death but no sclerotia, the levels of honeydew produced, total sclerotia weight and average sclerotia weight and size per spike. Ergot testing was undertaken in Canada and the UK. A major effect QTL, QCp.aafc.DH-2A, was detected in both the Canadian and UK experiments and had a significant effect on honeydew production levels. QCp.aafc.DH-5B had the biggest influence on total sclerotia weight per spike. QCp.aafc.DH-1B was only detected in the Canadian experiments and QCp.aafc.DH-5A in the UK experiment. An RNASeq analysis, undertaken to identify wheat differentially expressed genes associated with different combinations of the four ergot resistance QTL, revealed a disproportionate number of DEGs locating to the QCp.aafc.DH-1B, QCp.aafc.DH-2A and QCp.aafc.DH-5B QTL intervals.
Asunto(s)
Claviceps/patogenicidad , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Sitios de Carácter Cuantitativo , Triticum/genética , Genes de Plantas , Hordeum/genética , Hordeum/microbiología , Fenotipo , Poaceae/genética , Poaceae/microbiología , Transcripción Genética , Triticum/microbiologíaRESUMEN
Efficiency of yeast transformation is determined by the rate of yeast endocytosis. The aim of this study was to investigate the effect of introducing amino acids and other nutrients (inositol, adenine, or p-aminobenzoic acid) in the transformation medium to develop a highly efficient yeast transformation protocol. The target of rapamycin complex 1 (TORC1) kinase signalling complex influences the rate of yeast endocytosis. TORC signaling is induced by amino acids in the media. Here, we found that increasing the concentration of amino acids and other nutrients in the growth media lead to an increase yeast transformation efficiency up to 107 CFU per µg plasmid DNA and per 108 cells with a 13.8 kb plasmid DNA. This is over 130 times that of current published methods. This improvement may facilitate more efficient experimentation in which transformation efficiency is critical, such as yeast two-hybrid screening.