A novel signal transduction pathway involved in regulation of development and mycotoxin production in the filamentous fungus Aspergillus nidulans

真菌的发育和次生代谢受外界信号的调控。这些信号是如何被传递以诱导发育程序的，这在很大程度上是未知的。我们以前表明，MAPK相关的蛋白激酶ImeB的构巢曲霉参与调节的发展，响应于光和所需的真菌毒素杂色曲霉素（ST）的生产。通过这个项目，我的目标是阐明分子机制，ImeB如何有助于调节发育和真菌毒素的产生。首先，我将通过体外激酶测定和体内方法对ImeB进行全面表征。该项目的一个主要目的是鉴定在与ImeB共同的信号转导途径中起作用的因子，主要是调节ImeB的蛋白激酶和ImeB的底物。此外，我的目的是阐明，ImeB如何影响ST生物合成基因簇的表达，重点是ImeB对该簇的关键调控因子，特别是转录激活因子AflR的影响。发现在A.随后将nidulans应用于产生黄曲霉毒素的物种Aspergillusflavus。总之，这个项目应该有助于更好地了解控制丝状真菌的发展和真菌毒素生产的调控网络。

Fungal development and secondary metabolism is regulated by external signals. How such signals are transmitted to induce developmental programs is largely unknown. We previously showed that the MAPK-related protein kinase ImeB of Aspergillus nidulans is involved in the regulation of development in response to light and required for the production of the mycotoxin sterigmatocystin (ST). With this project, I aim to elucidate molecular mechanisms, how ImeB contributes to regulation of development and mycotoxin production. First, I will perform a comprehensive characterisation of ImeB, by in vitro kinase assays and by in vivo approaches. A major aim of this project is the identification of factors acting in a common signal transduction pathway with ImeB, primarily protein kinases regulating ImeB and substrates of ImeB. Furthermore, I aim to elucidate, how ImeB affects expression of the ST biosynthesis gene cluster, focussing on the influence of ImeB on key regulators of this cluster, particularly the transcriptional activator AflR. Findings in A. nidulans will be subsequently applied in the aflatoxin-producing species Aspergillus flavus. In summary, this project should help to better understand the regulatory network controlling development and mycotoxin production in filamentous fungi.