DFG Priority Programme SPP 1464

Programme Description

The actin cytoskeleton is a major determinant of cellular architecture throughout evolution. Despite its fundamental cell biological importance and its enormous implication in human diseases and therapy, many of the underlying regulatory functions have remained elusive for a long time. Only recently, in debt to the impact of the revolutionary gain of knowledge from the genome projects, an increasing number of regulatory mechanisms emerged that reflect the diversity of actin filament structures and functions through out the animal and plant kingdoms.

Actin filaments assemble from actin monomers at specified subcellular compartments in response to different signalling cascades. Owing to the fact that the stable association of actin monomers to form dimers and trimers (in a process termed nucleation) is thermodynamically unfavourable, and due to the activity of actin monomer binding proteins, no spontaneous actin polymerization occurs in cells. Thus, assembly of actin filaments requires factors that help to overcome this kinetic barrier to filament nucleation.

The aim of this programme is to investigate in an interdisciplinary network the structures, the functions, regulation and the interplay of these nucleators in order to correlate the diversity of nucleation mechanisms with the multitude of distinct cellular actin structures and functions.