Keratinocyte acetylcholine receptors regulate cell adhesion.
We investigated the mechanism mediating cholinergic control of cell-to-cell adhesion of human epidermal keratinocytes (KC) by non-neuronal acetylcholine produced by KC themselves. We first measured cholinergic effects on the expression of desmoglein (Dsg) 1 and 3 in KC using the semi-quantitative immunofluorescence and Western blot assays. Monolayers of KC were treated overnight with 0.25 mM of the cholinergic agonist carbachol (CCh) or the acetylcholinesterase inhibitor pyridostigmine bromide (PBr). Both CCh and PBr increased the relative amounts of Dsg 1 and Dsg 3. To determine the role for cholinergic receptor-mediated phosphorylation of Dsg molecules in assembly/disassembly of keratinocyte desmosomes, we tested the effects of a cholinergic antagonist on keratinocyte adhesion and Dsg phosphorylation status in DJM-1 cell line. Atropine (Atr), 0.02 mM, induced rapid detachment of cells from each other (acantholysis), and also increased phosphorylation of Dsg 3 by 33%. The Atr-dependent phosphorylation of Dsg 3 was inhibited in the presence of 0.5 mM CCh. Thus, keratinocyte cholinergic receptors regulate desmosomal adhesion of KC by altering the level of expression of both Dsg 1 and Dsg 3 and the phosphorylation status of Dsg 3.
Nguyen
Vu Thuong
VT
Department of Dermatology, University of California, School of Medicine, Davis, 4860 Y Street, #3400 Sacramento, CA 95817, USA.
Arredondo
Juan
J
Chernyavsky
Alexander I
AI
Kitajima
Yasuo
Y
Grando
Sergei A
SA
D000109:Acetylcholine / Q000096:biosynthesis / Q000502:physiology*; D015820:Cadherins / Q000096:biosynthesis; D002448:Cell Adhesion / Q000502:physiology*; D002478:Cells, Cultured; D018679:Cholinergic Agonists / Q000494:pharmacology; D051183:Desmoglein 1; D051184:Desmoglein 3; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism / Q000502:physiology*; D010766:Phosphorylation; D011950:Receptors, Cholinergic / Q000502:physiology*; D014407:Tumor Cells, Cultured
D015820:Cadherins; D018679:Cholinergic Agonists; C071894:DSG3 protein, human; D051183:Desmoglein 1; D051184:Desmoglein 3; D011950:Receptors, Cholinergic; D000109:Acetylcholine