S159: Systems biology of filamentous fungi

The impact of filamentous fungi on human activity is enormous. While pathogenic fungi are responsible for numerous deaths and billions of dollars in crop damage each year, fungi used in the bioprocessing industry are used to produce billions of dollars in beneficial products. In both cases fungal morphology along with the cell wall, and its material properties, plays a critical role. Yet, little is known about how regulatory mechanisms, or downstream effectors, impact morphology or cell wall material properties. We are using a systems biology approach to better understand cell-wall synthesis, its regulation and its impact on morphological development. As a first step in this process, we have systematically deleted a number of putative cell-wall related genes from the model fungus Aspergillus nidulans, and are using a sophisticated set of experimental tools to assess subsequent phenotypes providing insight regarding gene function. Proteomic analysis, of both cytoplasmic and cell-wall protein fractions, shows that these gene deletions affect a wide range of cellular processes.  Atomic force and electron microscopy indicate that particular gene deletions impact both cell-wall material properties and morphology. In addition, there appears to be a significant impact of some of these genes on overall mycelial morphogenesis, in particular regulation of fungal branching. The implications of these findings for the bioprocess industry will be discussed.