title: TRPV4-Mediated Detection of Hyposmotic Stress by Skin Keratinocytes Activates Developmental Immunity.
abstract: As an organism is exposed to pathogens during very early development, specific defense mechanisms must take effect. In this study, we used a germ-free zebrafish embryo model to show that osmotic stress regulates the activation of immunity and host protection in newly hatched embryos. Mechanistically, skin keratinocytes were responsible for both sensing the hyposmolarity of the aquatic environment and mediating immune effector mechanisms. This occurred through a transient potential receptor vanilloid 4/Ca(2+)/TGF-β-activated kinase 1/NF-κB signaling pathway. Surprisingly, the genes encoding antimicrobial effectors, which do not have the potential to cause tissue damage, are constitutively expressed during development, independently of both commensal microbes and osmotic stress. Our results reveal that osmotic stress is associated with the induction of developmental immunity in the absence of tissue damage and point out to the embryo skin as the first organ with full capacities to mount an innate immune response.
authors.affiliation: Department of Cell Biology and Histology, Faculty of Biology, Institute of Biomedical Research of Murcia-Arrixaca, Espinardo Campus, University of Murcia, 30100 Murcia, Spain; and jorge-galindo@usa.net vmulero@um.es.
authors.forename: Jorge
authors.identifier: http://orcid.org/0000-0002-4250-2477
authors.initials: J
authors.lastname: Galindo-Villegas
authors.affiliation: Department of Cell Biology and Histology, Faculty of Biology, Institute of Biomedical Research of Murcia-Arrixaca, Espinardo Campus, University of Murcia, 30100 Murcia, Spain; and.
authors.forename: Ana
authors.initials: A
authors.lastname: Montalban-Arques
authors.affiliation: Department of Cell Biology and Histology, Faculty of Biology, Institute of Biomedical Research of Murcia-Arrixaca, Espinardo Campus, University of Murcia, 30100 Murcia, Spain; and.
authors.forename: Sergio
authors.identifier: http://orcid.org/0000-0003-1004-4982
authors.initials: S
authors.lastname: Liarte
authors.affiliation: Department of Cell Biology and Histology, Faculty of Biology, Institute of Biomedical Research of Murcia-Arrixaca, Espinardo Campus, University of Murcia, 30100 Murcia, Spain; and.
authors.forename: Sofia
authors.initials: S
authors.lastname: de Oliveira
authors.affiliation: Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Pompeu Fabra University, 08002 Barcelona, Spain.
authors.forename: Carlos
authors.identifier: http://orcid.org/0000-0003-4083-0511
authors.initials: C
authors.lastname: Pardo-Pastor
authors.affiliation: Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Pompeu Fabra University, 08002 Barcelona, Spain.
authors.forename: Fanny
authors.identifier: http://orcid.org/0000-0002-3609-9992
authors.initials: F
authors.lastname: Rubio-Moscardo
authors.affiliation: Department of Cell Biology and Histology, Faculty of Biology, Institute of Biomedical Research of Murcia-Arrixaca, Espinardo Campus, University of Murcia, 30100 Murcia, Spain; and.
authors.forename: José
authors.initials: J
authors.lastname: Meseguer
authors.affiliation: Laboratory of Molecular Physiology and Channelopathies, Department of Experimental and Health Sciences, Pompeu Fabra University, 08002 Barcelona, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Valverde
authors.affiliation: Department of Cell Biology and Histology, Faculty of Biology, Institute of Biomedical Research of Murcia-Arrixaca, Espinardo Campus, University of Murcia, 30100 Murcia, Spain; and jorge-galindo@usa.net vmulero@um.es.
authors.forename: Victoriano
authors.identifier: http://orcid.org/0000-0001-9527-0211
authors.initials: V
authors.lastname: Mulero
mesh_terms: D000818:Animals; D004625:Embryo, Nonmammalian / Q000276:immunology; D005455:Fluorescent Antibody Technique; D007113:Immunity, Innate / Q000276:immunology*; D015603:Keratinocytes / Q000276:immunology*; D009997:Osmotic Pressure; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000196:embryology* / Q000276:immunology; D050916:TRPV Cation Channels / Q000276:immunology*; D059467:Transcriptome; D014162:Transfection; D015027:Zebrafish / Q000196:embryology* / Q000276:immunology*; D029961:Zebrafish Proteins / Q000276:immunology*
chemical_list: D050916:TRPV Cation Channels; C571237:TRPV4 protein, zebrafish; D029961:Zebrafish Proteins