title: Proteomic analysis of embryonic kidney development: Heterochromatin proteins as epigenetic regulators of nephrogenesis.
abstract: Elucidation of the mechanisms underlying the nephrogenesis will boost enormously the regenerative medicine. Here we performed 2-D gel-based comparative proteome analyses of rat embryonic kidney from different developmental stages. Out of 288 non-redundant identified proteins, 102 were common in all developmental stages. 86% of the proteins found in E14 and E16 were identical, in contrast only 37% of the identified proteins overlap between E14 and P1. Bioinformatics analysis suggests developmental stage-specific pathway activation and highlighted heterochromatin protein 1 (Cbx1, Cbx3, Cbx5) and Trim28 as potential key players in nephrogenesis. These are involved in the epigenetic regulation of gene silencing and were down-regulated in the course of kidney development. Trim28 is a potential epigenetic regulator of the branching inhibitor Bmp4. Silencing of Trim28 in cultured kidneys resulted in branching arrest. In contrast knockdown of Cbx5 was associated with abnormal ureteric bud growth and slight impairment of branching. ChIP analysis showed that the H3K9me3 distribution on Bmp4 promoters at E14 and E19 inversely correlate with mRNA expression levels. The concentrated expression-pattern of heterochromatin proteins and the negative impact of their silencing on kidney development, suggest an important role in reciprocal and inductive signaling between the ureteric bud and the metanephric mesenchyme.
authors.affiliation: Department of Nephrology and Rheumatology, Georg-August University Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany.
authors.forename: Gry H
authors.initials: GH
authors.lastname: Dihazi
authors.affiliation: Proteomics Group, Max-Planck-Institute of Experimental Medicine, Hermann-Rein-Strasse 3, D-37075 Göttingen, Germany.|Deutsche Forschungsgemeinschaft Research Center for Molecular Physiology of the Brain, Humboldtallee 23, D-37073 Göttingen, Germany.
authors.forename: Olaf
authors.initials: O
authors.lastname: Jahn
authors.affiliation: Department of Nephrology and Rheumatology, Georg-August University Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Tampe
authors.affiliation: Department of Nephrology and Rheumatology, Georg-August University Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Zeisberg
authors.affiliation: Department of Nephrology and Rheumatology, Georg-August University Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany.|Section for Transplantation- Immunology and Immunohematology, ZMF, Eberhard-Karls-University Tübingen, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Müller
authors.affiliation: Department of Nephrology and Rheumatology, Georg-August University Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany.
authors.forename: Gerhard A
authors.initials: GA
authors.lastname: Müller
authors.affiliation: Department of Nephrology and Rheumatology, Georg-August University Göttingen, Robert-Koch-Strasse 40, D-37075 Göttingen, Germany.
authors.forename: Hassan
authors.initials: H
authors.lastname: Dihazi
mesh_terms: D000818:Animals; D047369:Chromatin Immunoprecipitation; D000090266:Chromobox Protein Homolog 5; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D047108:Embryonic Development / Q000235:genetics; D044127:Epigenesis, Genetic; D055785:Gene Knockdown Techniques; D006570:Heterochromatin / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D007668:Kidney / Q000196:embryology* / Q000378:metabolism*; D038081:Organogenesis / Q000235:genetics; D025941:Protein Interaction Mapping; D060066:Protein Interaction Maps; D021381:Protein Transport; D020543:Proteome; D040901:Proteomics / Q000379:methods; D051381:Rats
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D006570:Heterochromatin; D006657:Histones; D020543:Proteome; D000090266:Chromobox Protein Homolog 5