PDF(Pubmed)
Abstract：
The asexual sporulation of filamentous fungi is an important mechanism for their reproduction, survival, and pathogenicity. In Aspergillus and several filamentous fungi, BrlA, AbaA, and WetA are the key elements of a central regulatory pathway controlling conidiation, and MedA is a developmental modifier that regulates temporal expression of central regulatory genes; however, their roles are largely unknown in nematode-trapping (NT) fungi. Arthrobotrys oligospora is a representative NT fungus, which can capture nematodes by producing adhesive networks (traps). Here, we characterized the function of AoMedA and three central developmental regulators (AoBrlA, AoAbaA, and AoWetA) in A. oligospora by gene disruption, phenotypic comparison, and multi-omics analyses, as these regulators are required for conidiation and play divergent roles in mycelial development, trap formation, lipid droplet accumulation, vacuole assembly, and secondary metabolism. A combined analysis of phenotypic traits and transcriptome showed that AoMedA and AoWetA are involved in the regulation of peroxisome, endocytosis, and autophagy. Moreover, yeast one-hybrid analysis showed that AoBrlA can regulate AoMedA, AoAbaA, and AoWetA, whereas AoMedA and AoAbaA can regulate AoWetA. Our results highlight the important roles of AoMedA, AoBrlA, AoAbaA, and AoWetA in conidiation, mycelia development, trap formation, and pathogenicity of A. oligospora and provide a basis for elucidating the relationship between conidiation and trap formation of NT fungi. IMPORTANCE Conidiation is the most common reproductive mode for many filamentous fungi and plays an essential role in the pathogenicity of fungal pathogens. Nematode-trapping (NT) fungi are a special group of filamentous fungi owing to their innate abilities to capture and digest nematodes by producing traps (trapping devices). Sporulation plays an important role in the growth and reproduction of NT fungi, and conidia are the basic components of biocontrol reagents for controlling diseases caused by plant-parasitic nematodes. Arthrobotrys oligospora is a well-known NT fungus and is a routinely used model fungus for probing the interaction between fungi and nematodes. In this study, the functions of four key regulators (AoMedA, AoBrlA, AoAbaA, and AoWetA) involved in conidiation were characterized in A. oligospora. A complex interaction between AoMedA and three central regulators was noted; these regulators are required for conidiation and trap formation and play a pleiotropic role in multiple intracellular activities. Our study first revealed the role of AoMedA and three central regulators in conidiation, trap formation, and pathogenicity of A. oligospora, which contributed to elucidating the regulatory mechanism of conidiation in NT fungi and helped in developing effective reagents for biocontrol of nematodes.
摘要：
丝状真菌的无性孢子形成是其繁殖的重要机制,生存,和致病性。在曲霉和几种丝状真菌中，Brla,AbaA,和WetA是控制分生孢子的中央调节途径的关键要素，和MedA是一个发育修饰，调节中央调控基因的时间表达;然而，它们在线虫诱捕（NT）真菌中的作用在很大程度上是未知的。Arthrobotrys寡孢子菌是一种具有代表性的NT真菌，它可以通过产生粘合剂网络（陷阱）捕获线虫。这里,我们描述了AoMedA和三个中心发育调节因子(AoBrlA，AoAbaA,和AoWetA）通过基因破坏在寡孢菌中，表型比较，和多组学分析，由于这些调节剂是分生孢子所必需的，并且在菌丝体发育中起着不同的作用，陷阱形成,脂滴积累，液泡组件，和次生代谢。对表型性状和转录组的联合分析表明，AoMedA和AoWetA参与了过氧化物酶体的调控，内吞作用,和自噬。此外，酵母单杂交分析表明,AoBrlA能调控AoMedA,AoAbaA,还有AoWetA,而AoMedA和AoAbaA可以调节AoWetA。我们的结果强调了AoMedA的重要作用，AoBrla,AoAbaA,和AoWetA在分生孢子中，菌丝体发育，陷阱形成,并为阐明NT真菌的分生孢子和陷阱形成之间的关系提供了依据。重要性分生法是许多丝状真菌最常见的繁殖方式，在真菌病原体的致病性中起着至关重要的作用。诱捕线虫（NT）真菌是一类特殊的丝状真菌，因为它们具有通过产生诱捕器（诱捕装置）来捕获和消化线虫的先天能力。孢子形成在NT真菌的生长和繁殖中起着重要作用，和分生孢子是控制植物寄生线虫引起的疾病的生物防治试剂的基本成分。Arthrobotrys寡孢子是一种众所周知的NT真菌，是一种常规使用的模型真菌，用于探测真菌和线虫之间的相互作用。在这项研究中,四个关键监管机构的职能(AoMedA，AoBrla,AoAbaA,和AoWetA）参与分生孢子的特征在于A.寡孢子。注意到AoMedA与三个中央调节剂之间的复杂相互作用；这些调节剂是分生孢子和陷阱形成所必需的，并且在多种细胞内活动中发挥多效性作用。我们的研究首次揭示了AoMedA和三个中央调节剂在分生孢子中的作用，陷阱形成,和A.寡孢子的致病性，这有助于阐明NT真菌分生孢子的调控机制，并有助于开发有效的线虫生物防治试剂。
