title: Maximal Expression of the Evolutionarily Conserved Slit2 Gene Promoter Requires Sp1.
abstract: Slit2 is a neural axon guidance and chemorepellent protein that stimulates motility in a variety of cell types. The role of Slit2 in neural development and neoplastic growth and migration has been well established, while the genetic mechanisms underlying regulation of the Slit2 gene have not. We identified the core and proximal promoter of Slit2 by mapping multiple transcriptional start sites, analyzing transcriptional activity, and confirming sequence homology for the Slit2 proximal promoter among a number of species. Deletion series and transient transfection identified the Slit2 proximal promoter as within 399 base pairs upstream of the start of transcription. A crucial region for full expression of the Slit2 proximal promoter lies between 399 base pairs and 296 base pairs upstream of the start of transcription. Computer modeling identified three transcription factor-binding consensus sites within this region, of which only site-directed mutagenesis of one of the two identified Sp1 consensus sites inhibited transcriptional activity of the Slit2 proximal promoter (-399 to +253). Bioinformatics analysis of the Slit2 proximal promoter -399 base pair to -296 base pair region shows high sequence conservation over twenty-two species, and that this region follows an expected pattern of sequence divergence through evolution.
authors.affiliation: Department of Biology, California State University Northridge, 18111 Nordhoff St., Northridge, CA, 91330, USA.
authors.forename: Jacquelyn
authors.initials: J
authors.lastname: Saunders
authors.affiliation: Department of Biology, California State University Northridge, 18111 Nordhoff St., Northridge, CA, 91330, USA.
authors.forename: D Roonalika
authors.initials: DR
authors.lastname: Wisidagama
authors.affiliation: Department of Biology, California State University Northridge, 18111 Nordhoff St., Northridge, CA, 91330, USA.
authors.forename: Travis
authors.initials: T
authors.lastname: Morford
authors.affiliation: Department of Biology, California State University Northridge, 18111 Nordhoff St., Northridge, CA, 91330, USA. cmalone@csun.edu.
authors.forename: Cindy S
authors.identifier: http://orcid.org/0000-0002-1607-2768
authors.initials: CS
authors.lastname: Malone
mesh_terms: D001483:Base Sequence / Q000235:genetics; D002460:Cell Line; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics*; D016297:Mutagenesis, Site-Directed / Q000379:methods; D009419:Nerve Tissue Proteins / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D017384:Sequence Deletion / Q000235:genetics; D016329:Sp1 Transcription Factor / Q000235:genetics* / Q000378:metabolism*; D014158:Transcription, Genetic / Q000235:genetics*; D015533:Transcriptional Activation / Q000235:genetics / Q000502:physiology*; D014162:Transfection / Q000379:methods; D000098552:Slit Homolog 2 Protein
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D016329:Sp1 Transcription Factor; D000098552:Slit Homolog 2 Protein
keywords: Evolution; Phylogenetics; Promoter; Slit2; Transcription