The predominant causal agent of poplar leaf blight is the pathogenic fungus Alternaria alternata (Fr.) Keissl., which exhibits host specificity toward Populus species. To elucidate the molecular response mechanisms of...The predominant causal agent of poplar leaf blight is the pathogenic fungus Alternaria alternata (Fr.) Keissl., which exhibits host specificity toward Populus species. To elucidate the molecular response mechanisms of A. alternata under fludioxonil fungicide stress, the fungus was cultured at the half-maximal effective concentration (EC₅₀) of fludioxonil. Transcriptomic and metabolomic profiles were analyzed using mycelia harvested under these conditions. Comparative analysis revealed 1,001 differentially expressed genes (DEGs) in the resistant strain (RS) relative to the wild-type strain (WT), comprising 628 upregulated and 373 downregulated genes. Concurrently, 524 differentially accumulated metabolites (DAMs) were identified, with 336 upregulated and 188 downregulated metabolites. KEGG pathway enrichment demonstrated pronounced upregulation in glycerophospholipid metabolism, α-linolenic acid metabolism, nucleic acid biosynthesis, and glycosylation processes. Conversely, arachidonic acid and galactose metabolism pathways were suppressed. Significant downregulation was observed in phosphatidylinositol signaling, aflatoxin biosynthesis, and cutin/suberin/wax biosynthesis pathways. Transcriptomic profiling further indicated that upregulated DEGs were predominantly associated with amino sugar/nucleotide sugar metabolism, ABC transporters, aflatoxin biosynthesis, and purine metabolism, while downregulated DEGs were enriched in N-glycan biosynthesis, endoplasmic reticulum protein processing, steroid biosynthesis, and riboflavin metabolism. Fludioxonil exerted substantial inhibitory effects on fungal growth, pathogenicity, and metabolic activity. Mechanistically, A. alternata counteracted fungicide-induced stress through modulation of its antioxidant defense system. This integrative multi-omics study delineates the dynamic gene expression and metabolic reprogramming in A. alternata under fludioxonil exposure, providing novel insights into potential molecular targets and informing the development of next-generation fungicidal strategies for phytopathogen control.展开更多
Leaf spot disease caused by Alternaria tenuissima seriously affects the yields of medicinal roots and cut flowers of Paeonia lactiflora.To mine the leaf spot resistance genes in P.lactiflora,we employed rapid amplific...Leaf spot disease caused by Alternaria tenuissima seriously affects the yields of medicinal roots and cut flowers of Paeonia lactiflora.To mine the leaf spot resistance genes in P.lactiflora,we employed rapid amplification of cDNA ends(RACE)to clone PlPR1 from the leaves of P.lactiflora.The results of bioinformatics analysis showed that the coding region of PlPR1 was 522 bp in length,and the encoded protein contained a typical CAP domain.Overexpression of PlPR1 in tobacco significantly decreased the disease index,delayed the disease progression,and attenuated the hypersensitive response induced by pathogen invasion in the transgenic plants.In conclusion,PlPR1 enhanced the plant resistance to the pathogen A.tenuissima by regulating the immune responses of plants.The findings provided a candidate target gene and a theoretical basis for breeding P.lactiflora varieties with disease resistance.展开更多
[Objective] The study aimed to establish a protoplast transformation system in Alternaria tenuissima. [Method] The protoplast of A.tenuissima was firstly prepared by enzymolysis method; then the yielded protoplast was...[Objective] The study aimed to establish a protoplast transformation system in Alternaria tenuissima. [Method] The protoplast of A.tenuissima was firstly prepared by enzymolysis method; then the yielded protoplast was transformed by G418 resistant DNA plasmid using PEG/CaCl2 method. [Result] The growth phenotype and PCR detection showed that resistance gene had integrated into A.tenuissima genome. The transformation efficiency of this method reached per μg DNA 3-4 transformants. After subculture thrice under nonselective condition, G418 resistance could still inherit stably. [Conclusion] The transformation system of A.tenuissima was successfully established, which laid basis for studying of the gene function of Alternaria tenuissima.展开更多
基金supported by the Northeast Asia Biodiversity Research Center(grant number 411147021003).
文摘The predominant causal agent of poplar leaf blight is the pathogenic fungus Alternaria alternata (Fr.) Keissl., which exhibits host specificity toward Populus species. To elucidate the molecular response mechanisms of A. alternata under fludioxonil fungicide stress, the fungus was cultured at the half-maximal effective concentration (EC₅₀) of fludioxonil. Transcriptomic and metabolomic profiles were analyzed using mycelia harvested under these conditions. Comparative analysis revealed 1,001 differentially expressed genes (DEGs) in the resistant strain (RS) relative to the wild-type strain (WT), comprising 628 upregulated and 373 downregulated genes. Concurrently, 524 differentially accumulated metabolites (DAMs) were identified, with 336 upregulated and 188 downregulated metabolites. KEGG pathway enrichment demonstrated pronounced upregulation in glycerophospholipid metabolism, α-linolenic acid metabolism, nucleic acid biosynthesis, and glycosylation processes. Conversely, arachidonic acid and galactose metabolism pathways were suppressed. Significant downregulation was observed in phosphatidylinositol signaling, aflatoxin biosynthesis, and cutin/suberin/wax biosynthesis pathways. Transcriptomic profiling further indicated that upregulated DEGs were predominantly associated with amino sugar/nucleotide sugar metabolism, ABC transporters, aflatoxin biosynthesis, and purine metabolism, while downregulated DEGs were enriched in N-glycan biosynthesis, endoplasmic reticulum protein processing, steroid biosynthesis, and riboflavin metabolism. Fludioxonil exerted substantial inhibitory effects on fungal growth, pathogenicity, and metabolic activity. Mechanistically, A. alternata counteracted fungicide-induced stress through modulation of its antioxidant defense system. This integrative multi-omics study delineates the dynamic gene expression and metabolic reprogramming in A. alternata under fludioxonil exposure, providing novel insights into potential molecular targets and informing the development of next-generation fungicidal strategies for phytopathogen control.
文摘Leaf spot disease caused by Alternaria tenuissima seriously affects the yields of medicinal roots and cut flowers of Paeonia lactiflora.To mine the leaf spot resistance genes in P.lactiflora,we employed rapid amplification of cDNA ends(RACE)to clone PlPR1 from the leaves of P.lactiflora.The results of bioinformatics analysis showed that the coding region of PlPR1 was 522 bp in length,and the encoded protein contained a typical CAP domain.Overexpression of PlPR1 in tobacco significantly decreased the disease index,delayed the disease progression,and attenuated the hypersensitive response induced by pathogen invasion in the transgenic plants.In conclusion,PlPR1 enhanced the plant resistance to the pathogen A.tenuissima by regulating the immune responses of plants.The findings provided a candidate target gene and a theoretical basis for breeding P.lactiflora varieties with disease resistance.
文摘[Objective] The study aimed to establish a protoplast transformation system in Alternaria tenuissima. [Method] The protoplast of A.tenuissima was firstly prepared by enzymolysis method; then the yielded protoplast was transformed by G418 resistant DNA plasmid using PEG/CaCl2 method. [Result] The growth phenotype and PCR detection showed that resistance gene had integrated into A.tenuissima genome. The transformation efficiency of this method reached per μg DNA 3-4 transformants. After subculture thrice under nonselective condition, G418 resistance could still inherit stably. [Conclusion] The transformation system of A.tenuissima was successfully established, which laid basis for studying of the gene function of Alternaria tenuissima.
