Interaction of plectin and intermediate filaments

BackgroundPlectin, a member of the plakin family proteins, is a high molecular weight protein that is ubiquitously expressed. It acts as a cytolinker for the three major components of the cyotoskeleton, namely actin microfilaments, microtubules and intermediate filaments.ObjectiveThe aim of our experiments was to identify new binding sites for intermediate filaments on plectin and to specify these sites.MethodsWe introduced truncated forms of plectin into several cell lines and observe interaction between plectin and intermediate filaments.ResultsWe found that a linker region in the COOH-terminal end of plectin was required for the association of the protein with intermediate filaments. In addition, we also demonstrated that a serine residue at position 4645 of plectin may have a role on binding of plectin to intermediate filaments.ConclusionA linker region in the COOH-terminal end and serine residue at position 4645 may be important for the binding of plectin to intermediate filaments.