title: deltaNp63 has a role in maintaining epithelial integrity in airway epithelium.
abstract: The upper airways are lined with a pseudostratified bronchial epithelium that forms a barrier against unwanted substances in breathing air. The transcription factor p63, which is important for stratification of skin epithelium, has been shown to be expressed in basal cells of the lungs and its ΔN isoform is recognized as a key player in squamous cell lung cancer. However, the role of p63 in formation and maintenance of bronchial epithelia is largely unknown. The objective of the current study was to determine the expression pattern of the ΔN and TA isoforms of p63 and the role of p63 in the development and maintenance of pseudostratified lung epithelium in situ and in culture. We used a human bronchial epithelial cell line with basal cell characteristics (VA10) to model bronchial epithelium in an air-liquid interface culture (ALI) and performed a lentiviral-based silencing of p63 to characterize the functional and phenotypic consequences of p63 loss. We demonstrate that ΔNp63 is the major isoform in the human lung and its expression was exclusively found in the basal cells lining the basement membrane of the bronchial epithelium. Knockdown of p63 affected proliferation and migration of VA10 cells and facilitated cellular senescence. Expression of p63 is critical for epithelial repair as demonstrated by wound healing assays. Importantly, generation of pseudostratified VA10 epithelium in the ALI setup depended on p63 expression and goblet cell differentiation, which can be induced by IL-13 stimulation, was abolished by the p63 knockdown. After knockdown of p63 in primary bronchial epithelial cells they did not proliferate and showed marked senescence. We conclude that these results strongly implicate p63 in the formation and maintenance of differentiated pseudostratified bronchial epithelium.
authors.affiliation: Stem Cell Research Unit, Biomedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland ; Department of Laboratory Hematology, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Ari Jon
authors.initials: AJ
authors.lastname: Arason
authors.affiliation: Institute of Immunobiology, Kantonal Hospital, St. Gallen, Switzerland.
authors.forename: Hulda R
authors.initials: HR
authors.lastname: Jonsdottir
authors.affiliation: Center for Systems Biology, University of Iceland, Reykjavik, Iceland.
authors.forename: Skarphedinn
authors.initials: S
authors.lastname: Halldorsson
authors.affiliation: Faculty of Pharmaceutical Sciences, University of Iceland, Reykjavik, Iceland.
authors.forename: Berglind Eva
authors.initials: BE
authors.lastname: Benediktsdottir
authors.affiliation: Stem Cell Research Unit, Biomedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
authors.forename: Jon Thor
authors.initials: JT
authors.lastname: Bergthorsson
authors.affiliation: Stem Cell Research Unit, Biomedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland ; Department of Laboratory Hematology, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Saevar
authors.initials: S
authors.lastname: Ingthorsson
authors.affiliation: Department of Pulmonary Medicine, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Olafur
authors.initials: O
authors.lastname: Baldursson
authors.affiliation: Department of Biochemistry, Center for Excellence in Bioinformatics and Life Sciences, State University of New York at Buffalo, United States of America.
authors.forename: Satrajit
authors.initials: S
authors.lastname: Sinha
authors.affiliation: Stem Cell Research Unit, Biomedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland ; Department of Laboratory Hematology, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Thorarinn
authors.initials: T
authors.lastname: Gudjonsson
authors.affiliation: Stem Cell Research Unit, Biomedical Center, Faculty of Medicine, University of Iceland, Reykjavik, Iceland ; Department of Pharmacology & Toxicology, Faculty of Medicine, University of Iceland, Reykjavik, Iceland ; Department of Laboratory Hematology, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Magnus K
authors.initials: MK
authors.lastname: Magnusson
mesh_terms: D017209:Apoptosis; D001980:Bronchi / Q000378:metabolism*; D002454:Cell Differentiation; D002460:Cell Line; D002465:Cell Movement; D049109:Cell Proliferation; D002470:Cell Survival; D016922:Cellular Senescence; D004848:Epithelium / Q000378:metabolism*; D005786:Gene Expression Regulation; D006801:Humans; D018793:Interleukin-13 / Q000378:metabolism; D016086:Lentivirus / Q000378:metabolism; D008168:Lung / Q000378:metabolism*; D010641:Phenotype; D020033:Protein Isoforms / Q000502:physiology; D014157:Transcription Factors / Q000502:physiology*; D025521:Tumor Suppressor Proteins / Q000502:physiology*; D014945:Wound Healing
chemical_list: D018793:Interleukin-13; D020033:Protein Isoforms; C115051:TP63 protein, human; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins