Das Zytoskelett:
Funktion und Regulation durch Rho-GTPasen

Einführung

Our team makes use of two eukaryotic model systems, the mouse and Dictyostelium discoideum, to investigate functional and regulatory aspects of the cytoskeleton. The cytoskeleton is a key player in almost all cellular processes, including motility, cytokinesis, cell-to-cell and cell-susbstrate interactions and intracellular transport. Actin-binding proteins contribute to the structural organization of the actin cytoskeleton by filament crosslinking (e.g. filamin, a-actinin) or bundling (e.g. villin, fimbrin). Other proteins anchor the cytoskeleton to the plasma membrane, nuclear envelope or cell-to-cell adhesion sites (e.g. spectrin, interaptin, plectin) and others, such as the myosins, mediate movement of cargoes along F-actin tracks.

Remodeling of the microfilament system is tightly regulated by signalling molecules. In particular, small GTPases of the Rho family are been extensively studied. They act as molecular switches, cycling between an active GTP-bound state and an inactive GDP-bound state. In its active state Rho GTPases interact with a multitude of effectors that relay upstream signals to cytoskeletal components, eliciting rearrangements of the actin cytoskeleton.

To better understand how the cytoskeleton works we use a combination of molecular biology (generation and analysis of knock out and transgenic models) as well as cell biology (immunofluorescence, video microscopy) approaches.