The antifungal protein PAF interferes with PKC/MPK and XXXX /PKA signalling of @entity14940 .

@entity268 @entity5834 @entity14940 @entity56 @entity5567 @entity7410
The Penicillium chrysogenum antifungal protein PAF inhibits polar growth and induces apoptosis in @entity14940 . We report here that two signalling cascades are implicated in its antifungal activity. PAF activates the @entity268 /protein kinase A (Pka) signalling cascade. A pkaA deletion mutant exhibited reduced sensitivity towards PAF. This was substantiated by the use of pharmacological modulators: PAF aggravated the effect of the activator @entity7410 and partially relieved the repressive activity of @entity5834 . Furthermore, the Pkc/mitogen-activated protein kinase (Mpk) signalling cascade mediated basal resistance to @entity5567 , which was independent of the small GTPase RhoA. Non-functional mutations of both genes resulted in @entity56 towards PAF. PAF did not increase MpkA phosphorylation or induce enzymes involved in the remodelling of the cell wall, which normally occurs in response to activators of the cell wall integrity pathway. Notably, PAF exposure resulted in actin gene repression and a deregulation of the chitin deposition at hyphal tips of A. nidulans, which offers an explanation for the morphological effects evoked by PAF and which could be attributed to the interconnection of the two signalling pathways. Thus, PAF represents an excellent tool to study signalling pathways in this model organism and to define potential fungal targets to develop new antifungals.
