title: Identification of a promoter element within the zebrafish colXalpha1 gene responsive to runx2 isoforms Osf2/Cbfa1 and til-1 but not to pebp2alphaA2.
abstract: Type X collagen is a short chain collagen specifically expressed by hypertrophic chondrocytes during endochondral ossification. We report here the functional analysis of the zebrafish (Danio rerio) collagen Xalpha1 gene (colXalpha1) promoter with the identification of a region responsive to two isoforms of the runt domain transcription factor runx2. Furthermore, we provide evidence for the presence of dual promoter usage in zebrafish, a finding that should be important to further understanding of the regulation of its restricted tissue distribution and spatial-temporal expression during early development. The zebrafish colXalpha1 gene structure is comparable to that recently identified by comparative genomics in takifugu and shows homology with corresponding mammalian genes, indicating that its general architecture has been maintained throughout vertebrate evolution. Our data suggest that, as in mammals, runx2 plays a role in the development of the osteogenic lineage, supporting zebrafish as a model for studies of bone and cartilage development.
authors.affiliation: Centro de Ciências do Mar do Algarve, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal.
authors.forename: B
authors.initials: B
authors.lastname: Simões
authors.forename: N
authors.initials: N
authors.lastname: Conceição
authors.forename: C S B
authors.initials: CS
authors.lastname: Viegas
authors.forename: J P
authors.initials: JP
authors.lastname: Pinto
authors.forename: P J
authors.initials: PJ
authors.lastname: Gavaia
authors.forename: L D
authors.initials: LD
authors.lastname: Hurst
authors.forename: R N
authors.initials: RN
authors.lastname: Kelsh
authors.forename: M L
authors.initials: ML
authors.lastname: Cancela
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001846:Bone Development / Q000235:genetics*; D003001:Cloning, Molecular; D024121:Collagen Type X / Q000235:genetics*; D050659:Core Binding Factor Alpha 1 Subunit / Q000378:metabolism*; D015870:Gene Expression; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010802:Phylogeny; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017385:Sequence Homology; D015533:Transcriptional Activation; D015027:Zebrafish / Q000235:genetics*
chemical_list: D024121:Collagen Type X; D050659:Core Binding Factor Alpha 1 Subunit; D020033:Protein Isoforms; D012333:RNA, Messenger