Poudel Bikram, Sathe Atul, Bede Jacqueline C, Kushalappa Ajjamada C
Plant Science Department, McGill University, Ste.-Anne-de-Bellevue, Quebec, Canada.
PLoS One. 2025 Jun 18;20(6):e0325702. doi: 10.1371/journal.pone.0325702. eCollection 2025.
Plants induce hypersensitive response programmed cell death (HR-PCD), upon biotrophic pathogen infection, to contain the pathogen to the point of infection. Apoptotic-like PCD (AL-PCD) has been reported upon prolonged hemibiotrophic and necrotrophic pathogen infection in potato, to feed on the dead cells for their growth. In potato, silencing of the gene StHRC lead to the suppression of AL-PCD, thus increasing resistance to blights in potato. This was also associated with a significant reduction in the expression of the metacaspase gene StMC7. Accordingly, the gene StMC7 was silenced in potato cultivar 'Russet Burbank' using CRISPR-Cas9 to improve disease resistance against late blight of potato caused by Phytophthora infestans. Following pathogen infection, the disease severity, pathogen biomass and StMC7 gene expression was lower in Stmc7 mutants as compared to wild type. Disease severity was also decreased in Alternaria solani inoculated Stmc7 mutants, compared to the wild type, suggesting possible multiple disease resistance in the Stmc7 knockdown mutants. This confirms that the silencing of StMC7 improves late blight disease resistance in potato.
植物在受到活体营养型病原体感染时会引发超敏反应程序性细胞死亡（HR-PCD），从而将病原体限制在感染部位。据报道，在马铃薯受到半活体营养型和死体营养型病原体长期感染后会出现凋亡样程序性细胞死亡（AL-PCD），病原体以死亡细胞为食来促进自身生长。在马铃薯中，基因StHRC的沉默导致AL-PCD受到抑制，从而增强了马铃薯对疫病的抗性。这还与metacaspase基因StMC7的表达显著降低有关。因此，利用CRISPR-Cas9技术在马铃薯品种“褐皮伯班克”中沉默基因StMC7，以提高对致病疫霉引起的马铃薯晚疫病的抗病性。病原体感染后，与野生型相比，Stmc7突变体中的病情严重程度、病原体生物量和StMC7基因表达均较低。与野生型相比，接种链格孢的Stmc7突变体的病情严重程度也有所降低，这表明Stmc7基因敲除突变体可能具有多种抗病性。这证实了StMC7的沉默提高了马铃薯对晚疫病的抗性。
