title: Delineation of the key aspects in the regulation of epithelial monolayer formation.
abstract: The formation, maintenance, and repair of epithelial barriers are of critical importance for whole-body homeostasis. However, the molecular events involved in epithelial tissue maturation are not fully established. To this end, we investigated the molecular processes involved in renal epithelial proximal-tubule monolayer maturation utilizing transcriptomic, metabolomic, and functional parameters. We uncovered profound dynamic alterations in transcriptional regulation, energy metabolism, and nutrient utilization over the maturation process. Proliferating cells exhibited high glycolytic rates and high transcript levels for fatty acid synthesis genes (FASN), whereas matured cells had low glycolytic rates, increased oxidative capacity, and preferentially expressed genes for beta oxidation. There were dynamic alterations in the expression and localization of several adherens (CDH1, -4, and -16) and tight junction (TJP3 and CLDN2 and -10) proteins. Genes involved in differentiated proximal-tubule function, cilium biogenesis (BBS1), and transport (ATP1A1 and ATP1B1) exhibited increased expression during epithelial maturation. Using TransAM transcription factor activity assays, we could demonstrate that p53 and FOXO1 were highly active in matured cells, whereas HIF1A and c-MYC were highly active in proliferating cells. The data presented here will be invaluable in the further delineation of the complex dynamic cellular processes involved in epithelial cell regulation.
authors.affiliation: Division of Physiology, Department of Physiology and Medical Physics, Innsbruck Medical University, Innsbruck, Austria.
authors.forename: Lydia
authors.initials: L
authors.lastname: Aschauer
authors.forename: Leonhard N
authors.initials: LN
authors.lastname: Gruber
authors.forename: Walter
authors.initials: W
authors.lastname: Pfaller
authors.forename: Alice
authors.initials: A
authors.lastname: Limonciel
authors.forename: Toby J
authors.initials: TJ
authors.lastname: Athersuch
authors.forename: Rachel
authors.initials: R
authors.lastname: Cavill
authors.forename: Abdulhameed
authors.initials: A
authors.lastname: Khan
authors.forename: Gerhard
authors.initials: G
authors.lastname: Gstraunthaler
authors.forename: Johannes
authors.initials: J
authors.lastname: Grillari
authors.forename: Regina
authors.initials: R
authors.lastname: Grillari
authors.forename: Philip
authors.initials: P
authors.lastname: Hewitt
authors.forename: Martin O
authors.initials: MO
authors.lastname: Leonard
authors.forename: Anja
authors.initials: A
authors.lastname: Wilmes
authors.forename: Paul
authors.initials: P
authors.lastname: Jennings
mesh_terms: D022005:Adherens Junctions / Q000378:metabolism; D015703:Antigens, CD; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D002448:Cell Adhesion; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D002923:Cilia; D057167:Claudins / Q000235:genetics / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology* / Q000502:physiology*; D005227:Fatty Acids / Q000378:metabolism; D016193:G1 Phase; D015870:Gene Expression; D020869:Gene Expression Profiling; D006003:Glycogen / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007687:Kidney Tubules, Proximal / Q000166:cytology*; D009682:Magnetic Resonance Spectroscopy; D008648:Mesoderm / Q000166:cytology / Q000502:physiology; D010100:Oxygen / Q000378:metabolism; D019098:Telomerase / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D015703:Antigens, CD; C513384:CDH1 protein, human; C114483:CDH16 protein, human; C491875:CLDN2 protein, human; D015820:Cadherins; D057167:Claudins; D005227:Fatty Acids; D014157:Transcription Factors; D006003:Glycogen; D019098:Telomerase; D010100:Oxygen