Polarized growth and the role of apical sterol-rich domains in Aspergillus nidulans

• Antragsteller: Dr. Norio Takeshita
• Fachliche Zuordnung: Zellbiologie
• Förderung: Förderung von 2012 bis 2016
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 215187193

Polarized growth of filamentous fungi depends on the microtubule (MT) and the actin cytoskeleton along with their associated motor proteins. Tip membrane-associated landmark proteins, so-called “cell end markers” link the two cytoskeletons. Recent results indicate that apical sterol-rich membrane domains (SRDs) play important roles in polarized growth and localization of cell end markers. SRDs are specific to fungi and thought to be formed by lipid raft clustering. In our preliminary study, we revealed that a flotillin orthologue, FloA, which serves as scaffold for raft formation at the membrane, is involved in the formation of SRDs. With the proposed research we are aiming to analyze the localization of SRDs (distribution of lipid raft clusters) in detail by super-resolution microscopy using FloA as a raft marker. To investigate the formation mechanism of SRDs, some candidate genes (actin-lipid binding proteins) are going to be analyzed by gene deletion and fluorescent protein tagging. To identify new genes involved in SRDs formation, genetic screens for multi-copy suppressors of sphingolipid synthesis mutants will be performed. To analyze the roles of SRDs on the integrity of the cytoskeletons, cell end markers, and growth machinery, we will analyze their localization in corresponding mutants of the genes identified in the reverse-genetic and the suppressor analysis.

• DFG-Verfahren: Sachbeihilfen