title: Pannexin 3 is a novel target for Runx2, expressed by osteoblasts and mature growth plate chondrocytes.
abstract: Pannexins are a class of chordate channel proteins identified by their homology to insect gap junction proteins. The pannexin family consists of three members, Panx1, Panx2, and Panx3, and the role each of these proteins plays in cellular processes is still under investigation. Previous reports of Panx3 expression indicate enrichment in skeletal tissues, so we have further investigated this distribution by surveying the developing mouse embryo with immunofluorescence. High levels of Panx3 were detected in intramembranous craniofacial flat bones, as well as long bones of the appendicular and axial skeleton. This distribution is the result of expression in both osteoblasts and hypertrophic chondrocytes. Furthermore, the Panx3 promoter contains putative binding sites for transcription factors involved in bone formation, and we show that the sequence between bases -275 and -283 is responsive to Runx2 activation. Taken together, our data suggests that Panx3 may serve an important role in bone development, and is a novel target for Runx2-dependent signaling.
authors.affiliation: Department of Cellular and Physiological Science, Life Sciences Institute, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Bond
authors.forename: Alice
authors.initials: A
authors.lastname: Lau
authors.forename: Silvia
authors.initials: S
authors.lastname: Penuela
authors.forename: Arthur V
authors.initials: AV
authors.lastname: Sampaio
authors.forename: T Michael
authors.initials: TM
authors.lastname: Underhill
authors.forename: Dale W
authors.initials: DW
authors.lastname: Laird
authors.forename: Christian C
authors.initials: CC
authors.lastname: Naus
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001842:Bone and Bones / Q000378:metabolism; D002454:Cell Differentiation; D019902:Chondrocytes / Q000378:metabolism* / Q000473:pathology; D017630:Connexins / Q000235:genetics / Q000378:metabolism*; D050659:Core Binding Factor Alpha 1 Subunit / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism; D047108:Embryonic Development; D006132:Growth Plate / Q000166:cytology*; D057809:HEK293 Cells; D006801:Humans; D006984:Hypertrophy; D051379:Mice; D041681:NIH 3T3 Cells; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D010012:Osteogenesis; D011401:Promoter Regions, Genetic / Q000235:genetics; D021381:Protein Transport; D051381:Rats; D015533:Transcriptional Activation / Q000235:genetics
chemical_list: D015415:Biomarkers; D017630:Connexins; D050659:Core Binding Factor Alpha 1 Subunit; C493716:Runx2 protein, mouse; C528477:pannexin 3 protein, mouse