The role of the dual compartment protein raver1 in cell polarity

• Applicant: Dr. Susanne Illenberger
• Subject Area: Cell Biology
• Term: from 2001 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5330768

Cell polarity, as required for the execution of cell-type specific functions in animal tissues, is generated by the cytoskeleton. Specifically, microfilaments are involved in the assembly of cell-cell contacts that divide a basolateral from an apical surface in stationary epithelial cells, but are also engaged in the development of a lamellipodium, defining temporarily the front of migrating fibroblasts. A variety of microfilament proteins has been identified as components of microfilament-membrane attachment sites as defined in cell contacts or in the periphery of a lamellipodium. In the proposed project, we would like to characterize a novel protein, raver1, which is a ligand for two microfilament attachment proteins, vinculin/metavinculin and alpha actinin, but also contains several consensus RNA binding motifs. Raver1 is primarily located in the nucleus, and in focal contacts of fibroblasts and in epithelial cell-cell contacts. The data so far available suggest that raver1 is expressed in high concentrations in well differentiated muscle, epithelial and fibroblastic cells but downregulated in transformed cells, and can shuttle between the cytoplasm and the nuclear compartment. We would like to clarify its potential role in transport of RNA and/or microfilament proteins involved in cell polarity.

• DFG Programme: Research Grants