The desmoplakin carboxyl terminus coaligns with and specifically disrupts intermediate filament networks when expressed in cultured cells

The function of desmoplakins I and II (DP I and DP II) in the combination of desmosomal plaque with cytoplasmic intermediate filaments (IF) was examined using a molecular genetic technique which employs an array of mammalian expression vectors. Light and electron microscopy revealed the colocalization of DP I and DP II with IF which disrupts the latter. Immunogold techniques revealed that the IF subunits were confined in mutant proteins around the nucleus. Results of further studies imply the involvement of the carboxyl terminus of DP in the attachment of IF to desmosomes.