title: The kidney-specific expression of genes can be modulated by the extracellular osmolality.
abstract: With this study, we wanted to prove the hypothesis that the unique extracellular osmolality within the renal medulla modulates a specific gene expression pattern. The physiologic functions of the kidneys are mediated by the segment-specific expression of key proteins. So far, we have limited knowledge about the mechanisms that control this gene expression pattern. The hyperosmolality in the renal medullary interstitium is of major importance as a driving force for urine concentration. We made use of primarily cultured rat renal inner medullary collecting-duct cells and microarray analysis to identify genes affected by the environmental osmolality of the culture medium. We identified hundreds of genes that were either induced or repressed in expression by hyperosmolality in a time- and osmolality-dependent fashion. Further analysis demonstrated that many of them, physiologically, showed a kidney- and even collecting-duct-specific expression, including secreted proteins, kinases, and transcription factors. On the other hand, we identified factors, down-regulated in expression, that have a diuretic effect. In conclusion, the kidney is the only organ that has such a hyperosmotic environment, and study provides an excellent method for controlling tissue-specific gene expression.-Schulze Blasum, B., Schröter, R., Neugebauer, U., Hofschröer, V., Pavenstädt, H., Ciarimboli, G., Schlatter E., Edemir, B. The kidney-specific expression of genes can be modulated by the extracellular osmolality.
authors.affiliation: Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany.
authors.forename: Britta
authors.initials: B
authors.lastname: Schulze Blasum
authors.affiliation: Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany.
authors.forename: Rita
authors.initials: R
authors.lastname: Schröter
authors.affiliation: Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Neugebauer
authors.affiliation: Institute of Physiology II, University of Münster, Münster, Germany; and.
authors.forename: Verena
authors.initials: V
authors.lastname: Hofschröer
authors.affiliation: Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany.
authors.forename: Hermann
authors.initials: H
authors.lastname: Pavenstädt
authors.affiliation: Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany.
authors.forename: Guiliano
authors.initials: G
authors.lastname: Ciarimboli
authors.affiliation: Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany.
authors.forename: Eberhard
authors.initials: E
authors.lastname: Schlatter
authors.affiliation: Department of Internal Medicine D, Experimental Nephrology, University of Münster, Münster, Germany; Faculty of Medicine, Department of Hematology and Oncology, Faculty of Medicine, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany bayram.edemir@uk-halle.de.
authors.forename: Bayram
authors.initials: B
authors.lastname: Edemir
mesh_terms: D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D005110:Extracellular Space / Q000187:drug effects; D015870:Gene Expression / Q000187:drug effects*; D007668:Kidney / Q000187:drug effects*; D009994:Osmolar Concentration; D017207:Rats, Sprague-Dawley; D012965:Sodium Chloride / Q000494:pharmacology*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D014157:Transcription Factors; D012965:Sodium Chloride
keywords: gene expression; microarray; tissue specific