title: Characterization of cis elements of the probasin promoter necessary for prostate-specific gene expression.
abstract: BACKGROUND
  The androgen-regulated probasin (PB) promoter has been used extensively to target transgenes to the prostate in transgenic mice; however, limited data exist on the mechanism that dictates prostate-specific gene expression. Tissue-specific gene expression involves synergistic effects among transcription factors associated in a complex bound to cis-acting DNA elements.
  
  
  METHODS
  Using comprehensive linker scan mutagenesis, enzyme mobility shift and supershift assays, chromatin immunoprecipitation, and transgenic animal studies, we have extensively characterized the prostate-specific PB promoter.
  
  
  RESULTS
  We identified a series of nonreceptor transcription factors that are bound to the prostate-specific rat PB promoter. These factors include several ubiquitously distributed proteins known to participate in steroid receptor-mediated transcription. In addition, we identified two tissue-specific DNA elements that are crucial in directing prostate-specific PB expression, and confirmed the functional importance of both elements in transgenic animal studies. These two elements are functionally interchangeable and can be bound by multiple protein complexes, including the forkhead transcription factor FoxA1, a "pioneer factor" that has a restricted distribution to some cells type that are ectoderm and endoderm in origin. Using transgenic mice, we further demonstrate that the minimal PB promoter region (-244/-96 bp) that encompasses these tissue-specific elements results in prostate-specific gene expression in transgenic mice, contains androgen receptor and FoxA1-binding sites, as well as ubiquitous transcription factor binding sites.
  
  
  CONCLUSIONS
  We propose that these sequence-specific DNA-binding proteins, including tissue-restricted and ubiquitous factors, create the first level of transcriptional control, which responds to intracellular pathways that directs prostate-specific gene expression.
authors.affiliation: Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, Tennessee.
authors.forename: JianFeng
authors.initials: J
authors.lastname: Zhang
authors.forename: Nan
authors.initials: N
authors.lastname: Gao
authors.forename: David J
authors.initials: DJ
authors.lastname: DeGraff
authors.forename: Xiuping
authors.initials: X
authors.lastname: Yu
authors.forename: Qian
authors.initials: Q
authors.lastname: Sun
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Case
authors.forename: Susan
authors.initials: S
authors.lastname: Kasper
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Matusik
mesh_terms: D000727:Androgen-Binding Protein / Q000235:genetics* / Q000378:metabolism; D000728:Androgens / Q000235:genetics; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D024202:Electrophoretic Mobility Shift Assay; D005786:Gene Expression Regulation / Q000235:genetics*; D006801:Humans; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic / Q000235:genetics*; D011467:Prostate / Q000378:metabolism*; D051381:Rats
chemical_list: D000727:Androgen-Binding Protein; D000728:Androgens; C027519:probasin