title: Nucleotide sequence conservation of novel and establishedcis-regulatory sites within the tyrosine hydroxylase gene promoter.
abstract: Tyrosine hydroxylase (TH) is the rate-limiting enzyme in catecholamine biosynthesis and its gene proximal promoter ( < 1 kb upstream from the transcription start site) is essential for regulating transcription in both the developing and adult nervous systems. Several putative regulatory elements within theTHproximal promoter have been reported, but evolutionary conservation of these elements has not been thoroughly investigated. Since many vertebrate species are used to model development, function and disorders of human catecholaminergic neurons, identifying evolutionarily conserved transcription regulatory mechanisms is a high priority. In this study, we alignTHproximal promoter nucleotide sequences from several vertebrate species to identify evolutionarily conserved motifs. This analysis identified three elements (a TATA box, cyclic AMP response element (CRE) and a 5'-GGTGG-3' site) that constitute the core of an ancient vertebrateTHpromoter. Focusing on only eutherian mammals, two regions of high conservation within the proximal promoter were identified: a ∼250 bp region adjacent to the transcription start site and a ∼85 bp region located approximately 350 bp further upstream. Within both regions, conservation of previously reportedcis-regulatory motifs and human single nucleotide variants was evaluated. Transcription reporter assays in aTH-expressing cell line demonstrated the functionality of highly conserved motifs in the proximal promoter regions and electromobility shift assays showed that brain-region specific complexes assemble on these motifs. These studies also identified a non-canonical CRE binding (CREB) protein recognition element in the proximal promoter. Together, these studies provide a detailed analysis of evolutionary conservation within theTHpromoter and identify potentialcis-regulatory motifs that underlie a core set of regulatory mechanisms in mammals.
authors.affiliation: Burke Medical Research Institute, White Plains, NY 10605, USA.
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.affiliation: Burke Medical Research Institute, White Plains, NY 10605, USA.
authors.forename: Kasturi
authors.initials: K
authors.lastname: Banerjee
authors.affiliation: Burke Medical Research Institute, White Plains, NY 10605, USA ; Weill Cornell Medical College Brain and Mind Research Institute, NY 10065, USA.
authors.forename: Harriet
authors.initials: H
authors.lastname: Baker
authors.affiliation: Burke Medical Research Institute, White Plains, NY 10605, USA ; Weill Cornell Medical College Brain and Mind Research Institute, NY 10065, USA.
authors.forename: John W
authors.initials: JW
authors.lastname: Cave
keywords: catecholamine; dopamine; evolution; transcription