May play a role in the integrity of hemidesmosome and the attachment of basal keratinocytes to the underlying basement membrane The 120 kDa linear IgA disease antigen is an anchoring filament component involved in dermal-epidermal cohesion. Is the target of linear IgA bullous dermatosis autoantibodies

Cell junction, hemidesmosomeMembraneSecreted, extracellular space, extracellular matrix, basement membrane

Epidermolysis bullosa, junctional 4, intermediate

A form of epidermolysis bullosa, a genodermatosis characterized by recurrent blistering, fragility of the skin and mucosal epithelia, and erosions caused by minor mechanical trauma. JEB4 is an autosomal recessive, intermediate form in which blistering lesions occur between the epidermis and the dermis at the lamina lucida level of the basement membrane zone. In intermediate forms of junctional epidermolysis bullosa, blistering does not lead to the formation of chronic granulation tissue and does not affect the lifespan of affected individuals. Nail dystrophy and dental enamel defects are present. Scarring or non-scarring alopecia and diffuse hair loss may occur. JEB4 patients manifest blisters at birth or shortly afterward. Blisters may heal with atrophic scarring and variable hypo- or hyperpigmentation. Oral mucosa may be involved.

Integrin alpha-6/beta-4 is a receptor for laminin. Plays a critical structural role in the hemidesmosome of epithelial cells. Is required for the regulation of keratinocyte polarity and motility. ITGA6:ITGB4 binds to NRG1 (via EGF domain) and this binding is essential for NRG1-ERBB signaling (PubMed:20682778). ITGA6:ITGB4 binds to IGF1 and this binding is essential for IGF1 signaling (PubMed:22351760). ITGA6:ITGB4 binds to IGF2 and this binding is essential for IGF2 signaling (PubMed:28873464)

Cell membraneCell junction, hemidesmosome

Epidermolysis bullosa, junctional 5A, intermediate

A form of epidermolysis bullosa, a genodermatosis characterized by recurrent blistering, fragility of the skin and mucosal epithelia, and erosions caused by minor mechanical trauma. JEB5A is an autosomal recessive, intermediate form in which blistering lesions occur between the epidermis and the dermis at the lamina lucida level of the basement membrane zone. In intermediate forms of junctional epidermolysis bullosa, blistering does not lead to the formation of chronic granulation tissue and does not affect the lifespan of affected individuals. Nail dystrophy and dental enamel defects are present. Scarring or non-scarring alopecia and diffuse hair loss may occur.