Beijing Key Laboratory for Forest Pest Control, College of Forestry, Beijing Forestry University, Beijing, China
Beijing Key Laboratory for Forest Pest Control, College of Forestry, Beijing Forestry University, Beijing, China.
mSphere. 2018 Sep 5;3(5):e00400-18. doi: 10.1128/mSphere.00400-18.
Iron homeostasis is essential for full virulence and viability in many pathogenic fungi. Here, we showed that the bZip transcription factor VdHapX functions as a key regulator of iron homeostasis for adaptation to iron-depleted and iron-excess conditions and is required for full virulence in the vascular wilt fungus, Deletion of impaired mycelial growth and conidiation under both iron starvation and iron sufficiency. Furthermore, disruption of led to decreased formation of the long-lived survival structures of , known as microsclerotia. Expression of genes involved in iron utilization pathways and siderophore biosynthesis was misregulated in the Δ strain under the iron-depleted condition. Additionally, the Δ strain exhibited increased sensitivity to high iron concentrations and HO, indicating that VdHapX also contributes to iron or HO detoxification. The Δ strain showed a strong reduction in virulence on smoke tree seedlings () and was delayed in its ability to penetrate plant epidermal tissue. This study demonstrated that VdHapX is a conserved protein that mediates adaptation to iron starvation and excesses, affects microsclerotium formation, and is crucial for virulence of .
铁稳态对于许多致病性真菌的完全毒力和生存能力至关重要。在这里，我们表明 bZip 转录因子 VdHapX 作为铁稳态的关键调节剂，可适应缺铁和铁过量的条件，并在血管萎蔫真菌 Deletion of 中完全毒力所必需。敲除 会导致菌丝生长和分生孢子形成在缺铁和铁充足条件下受损。此外，破坏 会导致被称为微菌核的长期存活结构的形成减少。在缺铁条件下，Δ 菌株中涉及铁利用途径和铁载体生物合成的基因表达被错误调控。此外，Δ 菌株对高铁浓度和 HO 的敏感性增加，表明 VdHapX 也有助于铁或 HO 的解毒。Δ 菌株在对烟树幼苗（）的毒力方面表现出强烈降低，并且在穿透植物表皮组织的能力方面延迟。这项研究表明，VdHapX 是一种保守蛋白，可介导对铁饥饿和过量的适应，影响微菌核的形成，并且对于 的毒力至关重要。
