title: Cleavage of desmoglein 3 can explain its depletion from keratinocytes in pemphigus vulgaris.
abstract: We have previously demonstrated that serum of patients with pemphigus vulgaris induces reduction of desmoglein 3 (Dsg3) half-life in keratinocytes (FEBS Lett 2006: 580: 3276). This phenomenon seems to occur as a consequence of the progressive depletion of Dsg3 from desmosomes. Here we reported that reduction of full-length Dsg3 may be due to its progressive cleavage, leading to the formation of two fragmentation products with apparent molecular masses of about 60 kDa (fragment 1) and 70 kDa (fragment 2), as revealed by Western blotting. Unexpectedly, analysis of fragmentation pattern suggested cleavage to occur intracellularly. Consistently, fragment 1 was shed and localized within the cytosol, as shown by living cell immunofluorescence microscopy. Total amounts of full-length plakoglobin and Dsg1 were apparently unchanged. Taken together, our findings provide evidence that proteolytic processing of Dsg3 can lead to depletion of Dsg3 from the cell.
authors.affiliation: Regional Center on Craniofacial Malformations-MRI, First School of Medicine and Surgery, Second University of Naples, Naples, Italy. cirillo.sun@libero.it
authors.forename: Nicola
authors.initials: N
authors.lastname: Cirillo
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Campisi
authors.forename: Fernando
authors.initials: F
authors.lastname: Gombos
authors.forename: Letizia
authors.initials: L
authors.lastname: Perillo
authors.forename: Felice
authors.initials: F
authors.lastname: Femiano
authors.forename: Alessandro
authors.initials: A
authors.lastname: Lanza
mesh_terms: D001798:Blood Proteins / Q000494:pharmacology; D015153:Blotting, Western; D002460:Cell Line; D051183:Desmoglein 1 / Q000378:metabolism; D051184:Desmoglein 3 / Q000378:metabolism*; D051180:Desmoplakins / Q000378:metabolism; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism* / Q000473:pathology*; D010392:Pemphigus / Q000378:metabolism* / Q000473:pathology*; D051185:gamma Catenin
chemical_list: D001798:Blood Proteins; C495297:DSG1 protein, human; C071894:DSG3 protein, human; D051183:Desmoglein 1; D051184:Desmoglein 3; D051180:Desmoplakins; C495292:JUP protein, human; D051185:gamma Catenin