The cAMP signaling pathway has been shown to be important in controlling morphological changes and pathogenicity in plant pathogens. In the present study, we identified PcPdeH, a gene encoding a high-affinity phosphodiesterase (PDE), which is a key regulator of the cAMP signaling pathway. To elucidate the function of PcPdeH, PcPdeH-knockout mutants were obtained using a type II CRISPR/Cas9 system in Phytophthora capsici. The knockout transformants of PcPdeH showed vegetative growth defects and abnormal cyst germination. Infection assays indicated that compared with the wild type, PcPdeH-knockout mutants showed significantly reduced virulence on pepper and tobacco leaves and exhibited increased (1.5-2-fold) cAMP levels relative to the wild-type and CK strains. Based on these phenotypic features, we propose that PcPdeH is crucial for vegetative growth, cyst germination and pathogenicity in P. capsici.

中文翻译：

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高亲和力磷酸二酯酶 PcPdeH 参与辣椒疫霉的极化生长和致病性


cAMP 信号通路已被证明对于控制植物病原体的形态变化和致病性非常重要。在本研究中，我们鉴定了 PcPdeH，一种编码高亲和力磷酸二酯酶 (PDE) 的基因，它是 cAMP 信号通路的关键调节因子。为了阐明 PcPdeH 的功能，使用 II 型 CRISPR/Cas9 系统在辣椒疫霉中获得了 PcPdeH 敲除突变体。 PcPdeH 敲除转化体表现出营养生长缺陷和异常的胞囊萌发。感染测定表明，与野生型相比，PcPdeH 敲除突变体对辣椒和烟草叶的毒力显着降低，并且与野生型和 CK 菌株相比，cAMP 水平增加（1.5-2 倍）。基于这些表型特征，我们认为 PcPdeH 对于辣椒疫病菌的营养生长、胞囊萌发和致病性至关重要。