title: Developmental and cell type-specific expression of the zinc finger transcription factor Krüppel-like factor 4 (Klf4) in postnatal mouse testis.
abstract: The transcription factor Krüppel-like factor 4 (Klf4, formerly gut-enriched Krüppel-like factor, GKLF) is specifically expressed in postproliferative epithelial cells such as those of the gut and the epidermis. The importance of Klf4 in terminal differentiation of keratinocytes has been demonstrated by targeted gene ablation in mice. Klf4-deficient mice fail to establish the barrier function of the skin and die shortly after birth due to dehydration. Based on these findings as well as in vitro studies, Klf4 was characterized as a transcription factor essential for postproliferative differentiation of epithelial cells. However, the testicular Klf4 expression pattern is completely unknown. Here, we demonstrate that Klf4 is developmentally regulated during postnatal testicular development of the mouse. Furthermore, we show strong expression in the postmeiotic germ cells undergoing final differentiation into sperm cells and provide evidence that Klf4 is also expressed in the somatic Sertoli cells. These findings suggest that Klf4 might play an important role in testicular differentiation in mammals.
authors.affiliation: Department of Genetics, University of Pennsylvania Medical School, Philadelphia, PA 19104, USA. ruediger.behr@uni-essen.de
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Behr
authors.forename: Klaus H
authors.initials: KH
authors.lastname: Kaestner
mesh_terms: D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D008297:Male; D051379:Mice; D012333:RNA, Messenger; D012671:Seminiferous Tubules / Q000378:metabolism; D012708:Sertoli Cells / Q000378:metabolism; D013094:Spermatozoa / Q000378:metabolism*; D013737:Testis / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics*; D016335:Zinc Fingers / Q000235:genetics*
chemical_list: D004268:DNA-Binding Proteins; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D012333:RNA, Messenger; D014157:Transcription Factors