Project Details
Projekt
Systematic Characterization of Cytochalasan Activities on Actin Dynamics in Mammalian Cells
Subject Area
Biological and Biomimetic Chemistry
Cell Biology
Cell Biology
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 438841444
Cytochalasans are known to inhibit cell division and various types of actin-based motility such as migration and platelet aggregation. Moreover, they were reported to affect processes less directly or evidently connected to actin dynamics, such as glucose transport, and to harbor antibiotic, anti-biofilm and antitumor activities. Whereas a large number of cytochalasans has been detected in fungal extracts, only few were hitherto isolated in sufficient amounts to probe their biological activities, and less than 15 are commercially available. Most of these are thought to directly block the polymerization of the fast growing ends of actin filaments, but a systematic characterization of the biochemical and cell biological commonalities and differences between their activities are so far missing. In this project, we will fill this gap of knowledge by teaming up within a novel research unit (FOR 5170) with several groups providing libraries of novel, mostly fungal cytochalasan isolates or derivatives of individual cytochalasans derived from semisynthesis or even total synthesis. All these cytochalasans will be systematically explored in various assays, probing their effects on the actin cytoskeleton and motility processes by various means and approaches. These will range from high-throughput screening of compound libraries with straight-forward phalloidin stainings of treated samples and low mag video microscopy of whole cell populations to more detailed, single cell characterization of the impact of selected cytochalasans or cytochalasan derivatives on subcellular actin structures and the turnover of filaments within them. In preliminary work, we have established sophisticated experimental approaches for cytochalasan analyses at various scales. Using these, we have already found exciting and specific differences between distinct cytochalasan variants, which will be followed by more in depth studies. Aside from these efforts, we will combine aforementioned screening and more detailed characterization methods with employing our continuously growing panels of genome-edited cell lines carrying disruptions of specific actin-binding proteins. This harbors the potential to unambiguously demonstrate distinct selectivities of specific cytochalasans or cytochalasan families for subsets of cellular actin filaments. Such knowledge would be instrumental for developing cytochalasans with specified biological activities. The latter will be exploited during the course of the work program along with studies on, for instance, various host-pathogen interactions. Finally, interesting cytochalasan activities will be immediately followed by their tuning with the help of the cytochalasan-derivatizing or -synthesizing groups within FOR5071, and complemented by biochemical and structural analyses in extramural collaborations.
DFG Programme
Research Units
