title: Simple Epithelial Keratins.
abstract: Simple epithelial keratins (SEKs) are the cytoplasmic intermediate filament proteins of single-layered and glandular epithelial cells as found in the liver, pancreas, intestine, and lung. SEKs have broad cytoprotective functions, which are facilitated by dynamic posttranslational modifications and interaction with associated proteins. SEK filaments are composed of obligate heteropolymers of type II (K7, K8) and type I (K18-K20, K23) keratins. The multifaceted roles of SEKs are increasingly appreciated due to findings obtained from transgenic mouse models and human studies that identified SEK variants in several digestive diseases. Reorganization of the SEK network into aggregates called Mallory-Denk bodies (MDBs) is characteristic for specific liver disorders such as alcoholic and nonalcoholic steatohepatitis. To spur further research on SEKs, we here review the methods and potential caveats of their isolation as well as possibilities to study them in cell culture. The existing transgenic SEK mouse models, their advantages and potential drawbacks are discussed. The tools to induce MDBs, ways of their visualization and quantification, as well as the possibilities to detect SEK variants in humans are summarized.
authors.affiliation: Department of Internal Medicine III and IZKF, University Hospital Aachen, Aachen, Germany. Electronic address: pstrnad@ukaachen.de.
authors.forename: Pavel
authors.initials: P
authors.lastname: Strnad
authors.affiliation: Department of Internal Medicine III and IZKF, University Hospital Aachen, Aachen, Germany.
authors.forename: Nurdan
authors.initials: N
authors.lastname: Guldiken
authors.affiliation: Faculty of Science and Engineering, Department of Biosciences, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Center for Disease Modeling, University of Turku, Turku, Finland.
authors.forename: Terhi O
authors.initials: TO
authors.lastname: Helenius
authors.affiliation: Faculty of Science and Engineering, Department of Biosciences, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Center for Disease Modeling, University of Turku, Turku, Finland.
authors.forename: Julia O
authors.initials: JO
authors.lastname: Misiorek
authors.affiliation: Faculty of Science and Engineering, Department of Biosciences, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Center for Disease Modeling, University of Turku, Turku, Finland.
authors.forename: Joel H
authors.initials: JH
authors.lastname: Nyström
authors.affiliation: Faculty of Science and Engineering, Department of Biosciences, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Center for Disease Modeling, University of Turku, Turku, Finland.
authors.forename: Iris A K
authors.initials: IA
authors.lastname: Lähdeniemi
authors.affiliation: Faculty of Science and Engineering, Department of Biosciences, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Center for Disease Modeling, University of Turku, Turku, Finland.
authors.forename: Jonas S G
authors.initials: JS
authors.lastname: Silvander
authors.affiliation: Department of Internal Medicine III and IZKF, University Hospital Aachen, Aachen, Germany.
authors.forename: Deniz
authors.initials: D
authors.lastname: Kuscuoglu
authors.affiliation: Faculty of Science and Engineering, Department of Biosciences, Cell Biology, Åbo Akademi University, Turku, Finland; Turku Center for Disease Modeling, University of Turku, Turku, Finland. Electronic address: dtoivola@abo.fi.
authors.forename: Diana M
authors.initials: DM
authors.lastname: Toivola
mesh_terms: D000818:Animals; D004847:Epithelial Cells / Q000378:metabolism*; D006801:Humans; D047468:Immunoprecipitation; D007633:Keratins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation
chemical_list: D007633:Keratins
keywords: Downregulation; High salt extract; Immunoprecipitation; Mutation; Overexpression