Recessive mutation in desmoplakin
disrupts desmoplakin-intermediate filament interactions and causes dilated cardiomyopathy, woolly hair and keratoderma.
Involvement of the RV or LV is dependant on the site of the mutation in patients carrying desmoplakin gene mutation.
Probands with TGF/3-3 gene mutation presented only non sustained ventricular tachycardia/ arrhythmias while probands carrying the mutation in the either desmoplakin or plakophilin-2 genes presented with all the four types--sustained ventricular tachycardia, non sustained VT (NVST), polymorphic ventricular complexes (PVCs) and ventricular fibrillation.
What probably happens first is association of things like envoplakin and involucrin to the site of the desmosome by cross-linking - more specifically, to the tail of desmoplakin, which extends 100 nm from the main plaque of the desmosome into the cytoplasm.
STEINERT: I assume you are referring to the amino terminus of desmoplakin? We have no information about its cross-linking to the cell envelope.
GUNDERSEN: Am I correct that, in your desmoplakin
dominant negative cell line, the intermediate filaments do not extend out to the cell periphery?
Two hybrid analysis reveals fundamental differences in direct interactions between desmoplakin
and cell type specific intermediate filaments.
Envoplakin, a novel precursor of the cornified envelope that has homology to desmoplakin
The cervix, fallopian tubes, and ovaries were free of tumor The glassy cells were positive for vimentin (Figure 5), neuron-specific enolase, protein gene product 9.5, p53 (80% with nuclear pattern), and Ki-67 (70%-80%) and negative for chromogranin A and B, CEA, smooth muscle actin, muscle-specific actin, CAM 5.2, 34[Beta]E12, Leu-5, CK7, CK19, CK20, CK22, desmoplakin
, desmin, myoglobin, HER-2 protein, and estrogen and progesterone receptors.
In addition, actin, epithelial membrane antigen, CD68, S100 protein, and desmoplakin
have been reported to be expressed in some FDC sarcomas.[2,3] However, these markers lack specificity, and their use without specific FDC markers can even lead to erroneous typing of spindle cell tumors.