title: Versican expression during skeletal/joint morphogenesis and patterning of muscle and nerve in the embryonic mouse limb.
abstract: Versican, an extracellular matrix proteoglycan, has been implicated in limb development and is expressed in precartilage mesenchymal condensations. However, studies have lacked precise spatial and temporal investigation of versican localization during skeletogenesis and its relationship to patterning of muscle and nerve during mammalian limb development. The transgenic mouse line hdf (heart defect), which bears a lacZ reporter construct disrupting Cspg2 encoding versican, allowed ready detection of hdf transgene expression through histochemical analysis. Hdf transgene expression in whole mount heterozygous embryos and localization of versican relative to cartilage, muscle, and nerve tissues in paraffin-embedded limb sections of wild-type embryos from 10.5-14 days postcoitum were evaluated by lacZ histochemistry, immunohistochemistry, and in situ hybridization. Versican was localized within precartilage condensations and nascent cartilages with expression diminishing during maturation of the cartilage model at later time points. Interestingly, versican remained highly expressed in developing synovial joint interzones, suggesting potential function for versican in joint morphogenesis. Isolated myoblasts, incipient skeletal muscle masses, and neurites were not present in areas of strong versican expression within the developing limb. Versican-expressing tissues may reserve space for the future limb skeleton and developing joints and may aid in patterning of muscle and nerve by deterring muscle migration and innervation into these regions.
authors.affiliation: Department of Biology, East Carolina University, Greenville, North Carolina 27858, USA.
authors.forename: Holly E
authors.initials: HE
authors.lastname: Snow
authors.forename: Lin M
authors.initials: LM
authors.lastname: Riccio
authors.forename: Corey H
authors.initials: CH
authors.lastname: Mjaatvedt
authors.forename: Stanley
authors.initials: S
authors.lastname: Hoffman
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Capehart
mesh_terms: D000818:Animals; D024722:Cardiac Myosins / Q000378:metabolism; D011508:Chondroitin Sulfate Proteoglycans / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D005121:Extremities / Q000196:embryology* / Q000502:physiology; D005260:Female; D018507:Gene Expression Regulation, Developmental; D037181:Lectins, C-Type; D051379:Mice; D008822:Mice, Transgenic; D009024:Morphogenesis; D009141:Musculoskeletal System / Q000196:embryology / Q000378:metabolism*; D018994:Myosin Light Chains / Q000378:metabolism; D009417:Nerve Tissue / Q000196:embryology*; D011509:Proteoglycans / Q000378:metabolism; D053675:Versicans
chemical_list: D011508:Chondroitin Sulfate Proteoglycans; D037181:Lectins, C-Type; D018994:Myosin Light Chains; D011509:Proteoglycans; C508323:Vcan protein, mouse; C107184:myosin light chain 2; D053675:Versicans; D024722:Cardiac Myosins