The dimorphic fungal pathogen, Zymoseptoria tritici undergoes discrete developmental changes to complete its life cycle on wheat. Molecular mechanisms underlying morphogenesis during infection process of Z. tritici are poorly understood. In this study, we have investigated the role of ZtVf1 gene encoding a transcription factor belonging to C2-H2 subfamily. In planta assays revealed that ZtVf1 is required for virulence. Reduced necrotic lesions and low pycnidia density within the lesions resulted in significantly reduced virulence of ZtVf1 mutants. Cytological analysis showed that the impaired virulence of ZtVf1 mutants attributed to reduced penetration and colonization along with hampered pycnidia differentiation. In vitro phenotyping showed that ZtVf1 deletion affects hyphal branching and biomass production suggesting that the reduced tissue colonization by the ZtVf1 mutant might be due to lower hyphal branching and less fungal biomass production. In addition, the majority of infected substomatal cavities by the ZtVf1 mutant filled with compacted mycelia mat that did not differentiate to mature pycnidia indicating that the impaired melanization negatively affected pycnidia formation and maturation. The ZtVf1 might target multiple genes belonging to different cellular processes whose identification is of eminent interest to increase our understanding of this pathosystem. Overall, the data provided in this study indicates that attenuated pathogenicity of ZtVf1 mutant is due to involvement of this gene in the regulation of both early and late stages of infection.

中文翻译：

---

ZtVf1转录因子调节小麦叶面病原体Zymoseptoria tritici的发育和毒力。

双态真菌病原体，Zymoseptoria tritici经历了离散的发育变化，以完成其在小麦上的生命周期。小麦Z.tritici感染过程中形态发生的分子机制了解甚少。在这项研究中，我们研究了编码属于C2-H2亚家族的转录因子的ZtVf1基因的作用。在植物试验中显示ZtVf1是毒力所必需的。坏死病灶的减少和病灶内伪孢子密度的降低导致ZtVf1突变体的毒力大大降低。细胞学分析表明，ZtVf1突变体的致病力降低归因于渗透力和定植能力的降低，以及伪狂犬病的分化受到阻碍。体外表型分析表明ZtVf1缺失会影响菌丝的分支和生物量的产生，这表明ZtVf1突变体减少的组织定植可能是由于菌丝的分支减少和真菌生物量的产生较少。此外，ZtVf1突变体感染的大多数感染的气孔下腔充满了致密的菌丝体垫，这些菌丝体垫未分化为成熟的伪孢子虫，这表明受损的黑色素化负面影响了伪孢子虫的形成和成熟。ZtVf1可能针对属于不同细胞过程的多个基因，这些基因的识别引起了我们的极大兴趣，以增进我们对这种病理系统的了解。全面的，