title: Expression of doublecortin reveals articular chondrocyte lineage in mouse embryonic limbs.
abstract: The doublecortin (Dcx) gene encodes a microtubule-binding protein that was originally found in immature neurons. In this study, we used two mouse strains that express reporter genes (LacZ and enhanced green fluorescence protein, respectively) driven by the endogenous Dcx promoter. We found that Dcx was expressed in the mesenchymal cells in the mouse embryonic limb buds. A population of the mesenchymal cells continued Dcx expression after they differentiated into joint interzone cells and then articular chondrocytes. In contrast, the endochondral chondrocytes lost Dcx expression when the mesenchymal cells differentiated into endochondral chondrocytes. These data support a concept that the articular and endochondral chondrocytes originate from the same mesenchymal cells that express Dcx. In contrast to the notion that articular chondrocytes are derived from de-differentiated endochondral chondrocytes, our findings demonstrate that the lineages of articular and endochondral chondrocytes bifurcate at the stage of endochondral chondrogenesis.
authors.affiliation: Department of Structural and Cellular Biology, Tulane Cancer Center, LCRC, Tulane Center for Aging, Tulane University School of Medicine, New Orleans, Louisiana 70112, USA.
authors.forename: Qiuyang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Alexander D
authors.initials: AD
authors.lastname: Cigan
authors.forename: Luis
authors.initials: L
authors.lastname: Marrero
authors.forename: Courtney
authors.initials: C
authors.lastname: Lopreore
authors.forename: Sen
authors.initials: S
authors.lastname: Liu
authors.forename: Dongxia
authors.initials: D
authors.lastname: Ge
authors.forename: Felix H
authors.initials: FH
authors.lastname: Savoie
authors.forename: Zongbing
authors.initials: Z
authors.lastname: You
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism*; D020219:Chondrogenesis; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D007596:Joints / Q000196:embryology*; D018878:Limb Buds / Q000196:embryology*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008869:Microtubule-Associated Proteins / Q000235:genetics* / Q000378:metabolism*; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism*
chemical_list: C000714847:Dcx protein, mouse; D000089622:Doublecortin Domain Proteins; D000089662:Doublecortin Protein; D008869:Microtubule-Associated Proteins; D009479:Neuropeptides