Desmosomal Mouse Overexpressions

Gene
Effects of Overexpression
Conclusions

Plakoglobin
Pg

Charpentier 2000

Suppresses proliferation in epidermis and hair. Reduces tumorogenicity and growth rate of highly transformed cells A function of plakoglobin may be the negative regulation of proliferation.

Desmocollin 1
Dsc1

Henkler 2000

Dsc1 is normally restricted to expression in suprabasal cells, but has been expressed in basal cells of transgenic mice. These mice have high levels of transgenic human Dsc1a experession in basal epidermal keratinocytes, however, do not display any abnormalities in skin histology, hair follicles, or desmosomal ultrastructure. The protein is distributed in a punctate fashion at the cell membrane, interacts with plakoglobiin, and efficiently incorporates into desmosomes. Desmocollin 1 is able to function in desmosomes of both basal and suprabasal cells. Desmocollin 1 is functionally equivalent to Desmocollin 3 in basal epidermal cells, and their changing expression patterns act as markers in the first step of keratinocyte differentiation.

Desmoglein 3
Dsg3

Allen 1996

Transgenic mice with NH2 terminally truncated desmoglein develop swelling of the paws, flakiness on their back, and blackenening of the tail tip. The intercellular spaces are widened, and there is altered desmosomal component organization. Desmosomes also reduce in number and are smaller in size. Altered integrin expression accompanies increased cell proliferation.

 

Mutations in desmoglein can disturb cell-cell adhesion in the epidermis, causing a cascade of changes within the skin.

Desmoglein 3
Dsg3

Elias 2001

Mice containing the Dsg3 transgene with an involucrin promotor and mouse Dsg3 FLAG cDNA exhibit an abnormal epidermal stratum corneum with scaling. Death occurs shortly after birth due to extreme dehydration. Premature loss of cohesion of corneocytes in stratum corneum is also evident. Abnormal Desmoglein 3 expression alters the stratum corneum structure, which affects the permeability layer of the epidermis.