IDC2 and IDC3, two genes involved in cell non-autonomous signaling of fruiting body development in the model fungus Podospora anserina

- IDC2 and IDC3 are new genes involved in signaling fruiting body development in Podospora anserina.
- Both genes act cell non-autonomously.
- Proteins encoded IDC2 and IDC3 required conserved cysteines for function.
- The IDC3 protein is located in vaculoes.
- The IDC2 proteins is likely located at the plasma membrane.

Filamentous ascomycetes produce complex multicellular structures during sexual reproduction. Little is known about the genetic pathways enabling the construction of such structures. Here, with a combination of classical and reverse genetic methods, as well as genetic mosaic and graft analyses, we identify and provide evidence for key roles for two genes during the formation of perithecia, the sexual fruiting bodies, of the filamentous fungus Podospora anserina. Data indicate that the proteins coded by these two genes function cell-non-autonomously and that their activity depends upon conserved cysteines, making them good candidate for being involved in the transmission of a reactive oxygen species (ROS) signal generated by the PaNox1 NADPH oxidase inside the maturing fruiting body towards the PaMpk1 MAP kinase, which is located inside the underlying mycelium, in which nutrients are stored. These data provide important new insights to our understanding of how fungi build multicellular structures.