“The cytoplasmic surface of intercellular junctions is a complex network of molecular interactions that link the extracellular region of the desmosomal cadherins with the cytoskeletal intermediate filaments. Although 3D structures of the major plaque components are known, the overall architecture remains unknown.” Al Amoudi et al, PNAS April 2011.
Theirs is the best diagram of the desmosome that I have found to date.
1) obvious lattice structure (periodicity)
2) intracellular lattice pretty much matches the periodicity of the extracellular lattice
“No intracellular molecular model for Dsc or Dsg “The structures of the cytoplasmic domains of desmoglein (Dsg) and desmocollin (Dsc) are not available. However, an alignment of their sequences with those of E-cadherin shows that most of the observed E-cadherin/β -catenin interactions are likely to be conserved in desmosomal cadherin/plakoglobin complexes. Therefore, we modeled plakoglobin-binding residues of desmosomal cadherins on the E-cadherin/β-catenin structure.” “Most of the cytoplasmic domain of Dscs (approximately 150 among approximately 200 aa) is modeled based on the E-cadherin/ β-catenin structure. The cytoplasmic region of Dsg is significantly larger and cannot be accounted for in our model. We speculate that the remaining region of the cytoplasmic domains of Dsg could span the region between the ODP and IDP, as proposed from sequence analysis (23), and thus it is not shown in our map of the ODP. According to Al Amoudi. Giving all credit to them, here is their diagram…. which needs some work, i know they know. Firstly they have made the intracellular and transmembrane portions of the moleules (Dsc and Dsg) the same, which they say are not the same. Secondly… i dont think the figure 8 shape is what is seen in TEMs, sometimes yes, but mostly no… so the orientation of these molecules needs some adjusting. Thirdly… the inner and outer intracytoplasmic dense plaques are not the same relative sizes… but their molecules here are the same size… and for all my observing of models of
