Hailey-Hailey disease and tight junctions: Claudins 1 and 4 are regulated by ATP2C1 gene encoding Ca(2+) /Mn(2+)  ATPase SPCA1 in cultured keratinocytes.
Mutations in the ATP2C1 gene encoding Ca(2+) /Mn(2+)  ATPase SPCA1 cause Hailey-Hailey disease (HHD, OMIM 16960). HHD is characterized by epidermal acantholysis. We attempted to model HHD using normal keratinocytes, in which the SPCA1 mRNA was down-regulated with the small inhibitory RNA (siRNA) method. SiRNA inhibition significantly down-regulated the SPCA1 mRNA, as demonstrated by qPCR, and decreased the SPCA1 protein beyond detectable level, as shown by Western analysis. The expression of selected desmosomal, adherens and tight junction (TJ) proteins was then studied in the SPCA1-deficient and control keratinocytes cultured in low (0.06 mm) or high (1.2 mm) calcium concentration. The mRNA and protein levels of most TJ components were up-regulated in non-treated control keratinocyte cultures upon switch from low to high calcium concentration. In contrast, SPCA1-deficient keratinocytes displayed high levels of TJ proteins claudins 1 and 4 even in low calcium. ZO-1 did not, however, follow similar expression patterns. Protein levels of occludin, beta-catenin, E-cadherin, desmoplakin, desmogleins 1-3, desmocollin 2/desmocollin 3 and plakoglobin did not show marked changes in SPCA1-deficient keratinocytes. Indirect immunofluorescence labelling revealed delayed translocation of desmoplakin and desmoglein 3 in desmosomes and increased intracellular pools of TJ and desmosomal components in SPCA1-inhibited keratinocytes. The results show that SPCA1 regulates the levels of claudins 1 and 4, but does not affect desmosomal protein levels, indicating that TJ proteins are differently regulated. The results also suggest a potential role for claudins in HHD.
Department of Dermatology, University of Turku and Turku University Hospital, Turku, Finland; Department of Cell Biology and Anatomy, University of Turku, Turku, Finland.
Laura
L
Raiko
Elina
E
Siljamäki
Mỹ G
MG
Mahoney
Heli
H
Putaala
Erkki
E
Suominen
Juha
J
Peltonen
Sirkku
S
Peltonen
D002118:Calcium / Q000494:pharmacology; D000252:Calcium-Transporting ATPases / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D062445:Claudin-1; D062506:Claudin-4; D057167:Claudins / Q000378:metabolism*; D051184:Desmoglein 3 / Q000378:metabolism; D051180:Desmoplakins / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D016506:Pemphigus, Benign Familial / Q000378:metabolism* / Q000503:physiopathology; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000494:pharmacology; D019108:Tight Junctions / Q000378:metabolism*
C568108:CLDN1 protein, human; C568157:CLDN4 protein, human; D062445:Claudin-1; D062506:Claudin-4; D057167:Claudins; D051184:Desmoglein 3; D051180:Desmoplakins; D008565:Membrane Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C403624:ATP2C1 protein, human; D000252:Calcium-Transporting ATPases; D002118:Calcium