Struktur und Funktion von SMOC-1 und SMOC-2, zwei neuen modulären, calciumbindenden und Basalmembran-assoziierten Proteinen (Structure and funcation of SMOC-1 und SMOC-2, two novel modular calcium-binding proteins associated with basement membranes)

• Applicant: Dr. Patrik Maurer
• Subject Area: Dermatology
• Term: from 2000 to 2003
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5250532

We have isolated two novel genes SMOC-1 and SMOC-2. They encode secreted modular proteins that contain a calcium-binding domain and are thus homologous to the BM-40 protein family. Nonetheless their domain composition is unique. RT-PCR data indicate a widespread expression in many tissues. Preliminary immunofluorescence studies with an antiserum directed against recombinant human SMOC-1 demonstrate a basement membrane localisation of the protein. We first want to analyse the expression of SMOC-1 and -2 during development and in adult mice, identify the cell types that express the proteins and investigate their localisation by electron microscopy. Recombinant SMOC-1 and -2 will be used to identify their binding partner(s) in basement membranes in biophysical studies. The relevance of these interactions will be verified by the demonstration of colocalisation in tissues. Domains responsible for binding activities will be identified and binding epitopes mapped. Based on these results relevant cell and organ culture systems will be selected and used to analyse the function in a cellular context. Crystallisation of the domain-specific fragments will be attempted to facilitate the future determination of three-dimensional structures. The genes will be mapped to prepare for the production of mice deficient in SMOC-1 and -2.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1086: Genetic and Molecular Analysis of Basement Membranes and Basement Membrane Anchorage