Crosstalk between PKA and MAPK signalling during mating in Ustilago maydis

玉米黑粉菌(Ustilago Maydis)中蛋白激酶A(PKA)和丝裂原活化蛋白激酶(MAPK)之间的串扰是真核信号网络的模型。在担子菌中，PKA/MAPK串扰是交配过程中信息素信号的关键，而信息素信号是致病发展的先决条件。最近，我们描述了一种新的串扰机制，证明了关键转录因子Prf1的活性受PKA和MAPK磷酸化的调节。这些激酶的差异磷酸化使Prf1能够区分不同的靶基因启动子。在拟议的项目中，我们希望回答PKA和MAPK磷酸化如何调节Prf1活性的问题。此外，由于MAPK信号对于特定的靶基因子集是需要的，我们想要解决第二个转录因子与MAPK磷酸化的Prf1协同作用的假设。

Crosstalk between protein kinase A (PKA) and mitogen-activated protein kinase (MAPK) in the corn pathogen Ustilago maydis serves as a model for eukaryotic signalling networks. In this basidiomycete PKA/MAPK crosstalk is crucial for pheromone signalling during mating, which is prerequisite for pathogenic development. Recently, we described a novel mechanism of crosstalk by demonstrating that the activity of the key transcription factor Prf1 is regulated by PKA as well as MAPK phosphorylation. The differential phosphorylation by these kinases enables Prf1 to discriminate various target gene promoters. In the proposed project we wish to answer the question how the activity of Prf1 is regulated by PKA as well as MAPK phosphorylation. In addition, since MAPK signalling is needed for a specific subset of target genes we want to address the hypothesis that a second transciption factor acts in concert with MAPK-phosphorylated Prf1.