title: Trps1 activates a network of secreted Wnt inhibitors and transcription factors crucial to vibrissa follicle morphogenesis.
abstract: Mutations in TRPS1 cause trichorhinophalangeal syndrome types I and III, which are characterized by sparse scalp hair in addition to craniofacial and skeletal abnormalities. Trps1 is a vertebrate transcription factor that contains nine zinc-finger domains, including a GATA-type zinc finger through which it binds DNA. Mice in which the GATA domain of Trps1 has been deleted (Trps1(Δgt/Δgt)) have a reduced number of pelage follicles and lack vibrissae follicles postnatally. To identify the transcriptional targets of Trps1 in the developing vibrissa follicle, we performed microarray hybridization analysis, comparing expression patterns in the whisker pads of wild-type versus Trps1(Δgt/Δgt) embryos. We identified a number of transcription factors and Wnt inhibitors among transcripts downregulated in the mutant embryos and several extracellular matrix proteins that were upregulated in the mutant samples, and demonstrated that target gene expression levels were altered in vivo in Trps1(Δgt/Δgt) vibrissae. Unexpectedly, we discovered that Trps1 can directly bind the promoters of its target genes to activate transcription, expanding upon its established role as a transcriptional repressor. Our findings identify Trps1 as a novel regulator of the Wnt signaling pathway and of early hair follicle progenitors in the developing vibrissa follicle.
authors: Department of Dermatology, Columbia University, New York, NY 10032, USA.
authors: Katherine A
authors: KA
authors: Fantauzzo
authors: Angela M
authors: AM
authors: Christiano
mesh_terms: D000818:Animals; D047369:Chromatin Immunoprecipitation; D017931:DNA Primers / Q000235:genetics; D005455:Fluorescent Antibody Technique; D050980:GATA Transcription Factors / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D018859:Hair Follicle / Q000196:embryology*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D051379:Mice; D046228:Microarray Analysis; D009024:Morphogenesis / Q000502:physiology*; D060888:Real-Time Polymerase Chain Reaction; D012097:Repressor Proteins; D014157:Transcription Factors / Q000378:metabolism*; D014738:Vibrissae / Q000196:embryology*; D051153:Wnt Proteins / Q000037:antagonists & inhibitors
chemical_list: D017931:DNA Primers; D050980:GATA Transcription Factors; D012097:Repressor Proteins; D014157:Transcription Factors; C525953:Trps1 protein, mouse; D051153:Wnt Proteins