title: Specific binding of Clostridium perfringens enterotoxin fragment to Claudin-b and modulation of zebrafish epidermal barrier.
abstract: Claudins (Cldn) are the major components of tight junctions (TJs) sealing the paracellular cleft in tissue barriers of various organs. Zebrafish Cldnb, the homolog of mammalian Cldn4, is expressed at epithelial cell-cell contacts and is important for regulating epidermal permeability. The bacterial toxin Clostridium perfringens enterotoxin (CPE) has been shown to bind to a subset of mammalian Cldns. In this study, we used the Cldn-binding C-terminal domain of CPE (194-319 amino acids, cCPE 194-319 ) to investigate its functional role in modulating zebrafish larval epidermal barriers. In vitro analyses show that cCPE 194-319 removed Cldn4 from epithelial cells and disrupted the monolayer tightness, which could be rescued by the removal of cCPE 194-319. Incubation of zebrafish larvae with cCPE 194-319 removed Cldnb specifically from the epidermal cell membrane. Dye diffusion analysis with 4-kDa fluorescent dextran indicated that the permeability of the epidermal barrier increased due to cCPE 194-319 incubation. Electron microscopic investigation revealed reversible loss of TJ integrity by Cldnb removal. Collectively, these results suggest that cCPE 194-319 could be used as a Cldnb modulator to transiently open the epidermal barrier in zebrafish. In addition, zebrafish might be used as an in vivo system to investigate the capability of cCPE to enhance drug delivery across tissue barriers.
authors: Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China.|Leibniz Institut für Molekulare Pharmakologie, Berlin, Germany.
authors: Jingjing
authors: J
authors: Zhang
authors: The First Affiliated Hospital of Zhengzhou University, No.1 Jianshe East Road, Zhengzhou, 450052, Henan Province, China.
authors: Chen
authors: C
authors: Ni
authors: Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China.
authors: Zhenguo
authors: Z
authors: Yang
authors: Leibniz Institut für Molekulare Pharmakologie, Berlin, Germany.
authors: Anna
authors: A
authors: Piontek
authors: Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China.
authors: Huapu
authors: H
authors: Chen
authors: Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China.
authors: Sijie
authors: S
authors: Wang
authors: Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China.
authors: Yiming
authors: Y
authors: Fan
authors: Key Laboratory of Protein and Peptide Pharmaceuticals, Chinese Academy of Sciences-University of Tokyo Joint Laboratory of Structural Virology and Immunology, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
authors: Zhihai
authors: Z
authors: Qin
authors: Institute of Clinical Physiology, Charité -Universitätsmedizin Berlin, Berlin, Germany.
authors: Joerg
authors: J
authors: Piontek
mesh_terms: D000818:Animals; D062506:Claudin-4 / Q000378:metabolism; D057167:Claudins / Q000378:metabolism*; D004058:Diffusion; D004285:Dogs; D016503:Drug Delivery Systems; D004768:Enterotoxins / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D004817:Epidermis / Q000378:metabolism*; D005456:Fluorescent Dyes / Q000493:pharmacokinetics; D007814:Larva; D061985:Madin Darby Canine Kidney Cells; D051379:Mice; D008807:Mice, Inbred BALB C; D060172:Morpholinos / Q000494:pharmacology; D010446:Peptide Fragments / Q000378:metabolism / Q000494:pharmacology; D011485:Protein Binding; D060066:Protein Interaction Maps; D011993:Recombinant Fusion Proteins / Q000493:pharmacokinetics; D012235:Rhodamines / Q000493:pharmacokinetics; D012869:Skin Absorption / Q000187:drug effects*; D019108:Tight Junctions / Q000187:drug effects* / Q000378:metabolism; D015027:Zebrafish / Q000254:growth & development / Q000378:metabolism; D029961:Zebrafish Proteins / Q000378:metabolism*
chemical_list: D062506:Claudin-4; D057167:Claudins; C000607512:Cldnb protein, zebrafish; D004768:Enterotoxins; D005456:Fluorescent Dyes; D060172:Morpholinos; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D012235:Rhodamines; D029961:Zebrafish Proteins; C035598:enterotoxin, Clostridium; C029773:rhodamine B
keywords: Claudin-4; Claudin-b; Clostridium perfringens enterotoxin; epidermal barrier; tight junction