Desmosomal glycoproteins

Immunoblot analyses with antibodies specific for the transmembranal desmosomal glycoprotein desmoglein I (DGI) of plantar stratum corneum undergoing spontaneous cell dissociation30 showed that although the still cohesive tissue contained only intact DG I, dissociated cells contained no... 

Walsh, A. and Chapman, S.J., Sugars protect desmosome and corneosome glycoproteins from proteolysis, Arch. Dermatol. Res., 283, 174, 1991. 

Changes in glycosylation can readily be invoked to explain how defects develop at the cell surface and there is much evidence in favour of this, but they can equally be used to account for alterations in the endomembranes. For example, changes in the major mitochondrial glycoprotein could lead to the observed defects in the handling of calcium in the mitochondria of many tumour cells, the development of mitochondrial inclusions, the loss of the Pasteur effect and the absence of specific cell-cell adhesions such as desmosomes. With endomembranes much less information is available than for the cell surface, but such evidence as there is broadly supports this type of proposition. 

In the replicas, the unmodified number of membrane associated particles is no surprise, since this disease shows a normal mitotic index The usual arrangement of membrane associated particles in correspondence with the desmosomes substantiates thin section observations. On the contrary, the absence or the low number of gap junctions found is an Interesting fact. This phenomenon can possibly be ascribed to a vitamin A deficiency since, as is well known, this substance stimulates the synthesis of glycoproteins and RNA , binds to plasma proteins and has been experimentally shown to induce the formation of gap junctions . 

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