Responding to external signals and adaptation to changes in the milieu is indispensable for the viability of all living organisms. Aspergillus fumigatus, a sophisticated saprophytic fungus is able to grow and proliferate in a variety of environments. Fungal pathogens such as A. fumigatus employ signal transduction cascades such as Mitogen Activated Protein Kinase (MAPK) pathways to sense, transduce and regulate different developmental processes of the fungal cell in response to extracellular cues. The genome of A. fumigatus harbours four MAPK genes. One of them, named as MpkA, has been shown to be a key player of the cell wall integrity (CWI) pathway of A. fumigatus. We made a comprehensive study of the role of the CWI pathway in A. fumigatus. We found that MpkA regulated CWI signalling is involved in regulation of plethora of genes ranging from those involved in cell wall repair and synthesis, defence against oxidative stress, pigment and toxin biosynthesis. Furthermore, MpkA effects ornithine and polyamines biosynthesis depleting the main substrate for siderophore production during iron starvation. In conclusion, MpkA can perform all those functions by fine tuning the balance between the energy invested in various cellular processes required for growth, development and natural product synthesis. It thereby, acts as a regulator to ensure better survival of the fungal cell under a wide variety of conditions.
Full conference title:
26th Fungal Genetics Conference
- Fungal Genetics Conference 26th (2005)