Department of Integrative Biology, Kyungpook National University, Daegu 41566, Republic of Korea.
School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
J Microbiol Biotechnol. 2023 Nov 28;33(11):1420-1427. doi: 10.4014/jmb.2307.07009. Epub 2023 Aug 4.
The forkhead domain genes are important for development and morphogenesis in fungi. Six forkhead genes - have been found in the genome of the model filamentous Ascomycete . To identify the gene(s) associated with fungal development, we examined mRNA levels of these six genes and found that the level of and mRNA was significantly elevated during asexual development and in conidia. To investigate the roles of FkhB and FkhD, we generated and deletion mutants and complemented strains and investigated their phenotypes. The deletion of , but not , affected fungal growth and both sexual and asexual development. The deletion mutant exhibited decreased colony size with distinctly pigmented (reddish) asexual spores and a significantly lower number of conidia compared with these features in the wild type (WT), although the level of sterigmatocystin was unaffected by the absence of . Furthermore, the deletion mutant produced sexual fruiting bodies (cleistothecia) smaller than those of WT, implying that the gene is involved in both asexual and sexual development. In addition, deletion reduced fungal tolerance to heat stress and decreased trehalose accumulation in conidia. Overall, these results suggest that plays a key role in proper fungal growth, development, and conidial stress tolerance in .
叉头框结构域基因在真菌的发育和形态发生中非常重要。在丝状子囊菌的模式生物中已经发现了六个叉头基因。为了鉴定与真菌发育相关的基因，我们检测了这六个基因的 mRNA 水平，发现和的 mRNA 水平在无性发育和分生孢子中显著升高。为了研究 FkhB 和 FkhD 的作用，我们生成了和缺失突变体和互补菌株，并研究了它们的表型。缺失，但不缺失，影响真菌的生长和有性和无性发育。与野生型（WT）相比，缺失突变体的菌落大小减小，无性孢子明显着色（红色），分生孢子数量明显减少，尽管不存在时，麦角固醇的水平不受影响。此外，缺失突变体产生的有性生殖体（闭囊壳）比 WT 小，这表明该基因参与无性和有性发育。此外，缺失减少了真菌对热应激的耐受性，并降低了分生孢子中的海藻糖积累。总的来说，这些结果表明在中，发挥关键作用适当的真菌生长，发育和分生孢子应激耐受性。
