title: Quantitative proteome analysis of alveolar type-II cells reveals a connection of integrin receptor subunits beta 2/6 and WNT signaling.
abstract: Alveolar type-II cells (ATII cells) are lung progenitor cells responsible for regeneration of alveolar epithelium during homeostatic turnover and in response to injury. Characterization of ATII cells will have a profound impact on our understanding and treatment of lung disease. The identification of novel ATII cell-surface proteins can be used for sorting and enrichment of these cells for further characterization. Here we combined a high-resolution mass spectrometry-based membrane proteomic approach using lungs of the SILAC mice with an Affymetrix microarray-based transcriptome analysis of ATII cells. We identified 16 proteins that are enriched in the membrane fraction of ATII cells and whose genes are highly expressed in these cells. Interestingly, we confirmed our data for two of these genes, integrin beta 2 and 6 (Itgb2 and Itgb6), by qRT-PCR expression analysis and Western blot analysis of protein extracts. Moreover, flow cytometry and immunohistochemistry in adult lung revealed that ITGB2 and ITGB6 are present in subpopulations of surfactant-associated-protein-C-positive cells, suggesting the existence of different types of ATII cells. Furthermore, analysis of the Itgb2(-/-) mice showed that Itgb2 is required for proper WNT signaling regulation in the lung.
authors.affiliation: LOEWE Research Group Lung Cancer Epigenetic, ‡Division of Biomolecular Mass Spectrometry, §Department of Lung Development and Remodeling, and ∥Department of Cardiac Development and Remodeling, Max-Planck-Institute for Heart and Lung Research, member of the Universities of Giessen and Marburg Lung Center (UGMLC) and German Center of Lung Research (DZL) , Parkstraße 1, 61231 Bad Nauheim, Germany.
authors.forename: Regina T
authors.initials: RT
authors.lastname: Mukhametshina
authors.forename: Aaron
authors.initials: A
authors.lastname: Ruhs
authors.forename: Indrabahadur
authors.initials: I
authors.lastname: Singh
authors.forename: Diya
authors.initials: D
authors.lastname: Hasan
authors.forename: Adriana
authors.initials: A
authors.lastname: Contreras
authors.forename: Aditi
authors.initials: A
authors.lastname: Mehta
authors.forename: Vandana S
authors.initials: VS
authors.lastname: Nikam
authors.forename: Katrin
authors.initials: K
authors.lastname: Ahlbrecht
authors.forename: Gianni
authors.initials: G
authors.lastname: Carraro
authors.forename: Hector A
authors.initials: HA
authors.lastname: Cabrera-Fuentes
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Jiang
authors.forename: Robert
authors.initials: R
authors.lastname: Voswinckel
authors.forename: Werner
authors.initials: W
authors.lastname: Seeger
authors.forename: Saverio
authors.initials: S
authors.lastname: Bellusci
authors.forename: Karin
authors.initials: K
authors.lastname: Scharffetter-Kochanek
authors.forename: Tatyana V
authors.initials: TV
authors.lastname: Bagaeva
authors.forename: Klaus T
authors.initials: KT
authors.lastname: Preissner
authors.forename: Thomas
authors.initials: T
authors.lastname: Boettger
authors.forename: Thomas
authors.initials: T
authors.lastname: Braun
authors.forename: Marcus
authors.initials: M
authors.lastname: Krüger
authors.forename: Guillermo
authors.initials: G
authors.lastname: Barreto
mesh_terms: D000818:Animals; D018821:CD18 Antigens / Q000235:genetics* / Q000378:metabolism; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D005786:Gene Expression Regulation; D039641:Integrin beta Chains / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D058977:Molecular Sequence Annotation; D011485:Protein Binding; D011486:Protein C / Q000235:genetics / Q000378:metabolism; D020543:Proteome / Q000235:genetics* / Q000378:metabolism; D011650:Pulmonary Alveoli / Q000166:cytology / Q000378:metabolism; D020545:Respiratory Mucosa / Q000166:cytology / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism*; D046888:Tissue Array Analysis; D060449:Wnt Signaling Pathway / Q000235:genetics*
chemical_list: D018821:CD18 Antigens; D039641:Integrin beta Chains; D011486:Protein C; D020543:Proteome; C072170:integrin beta6