Limb chondrogenesis is compromised in the versican deficient hdf mouse.
It has been suggested that the matrix proteoglycan, versican, may perform a functional role during early events of limb skeletogenesis largely by virtue of its spatiotemporal expression pattern in precartilage mesenchymal aggregations. The versican-deficient hdf transgenic mouse has provided the first model to explore the implications of a null mature versican on limb chondrogenesis. Due to lethality of hdf homozygous embryos prior to limb cartilage differentiation, high-density micromass cultures were employed to compare the chondrogenic capacity of hdf mutant limb mesenchyme to that of wild-type. In homozygous hdf mesenchyme, aggregation was severely compromised and neither cartilage-characteristic Type II collagen nor alcian blue positive foci were detected during a 6-day period of culture. Three-dimensional culture of hdf mutant mesenchyme, however, showed that in a permissive environment mutant cells also expressed Type II collagen. Results strongly suggest that mature versican proteoglycan is essential for precartilage aggregation and subsequent cartilage differentiation.
Williams
Dennis R
DR
Department of Biology, East Carolina University, Greenville, NC, USA.
Presar
Ashley R
AR
Richmond
A Todd
AT
Mjaatvedt
Corey H
CH
Hoffman
Stanley
S
Capehart
Anthony A
AA
D000818:Animals; D020219:Chondrogenesis / Q000235:genetics*; D011508:Chondroitin Sulfate Proteoglycans / Q000172:deficiency*; D024043:Collagen Type II / Q000378:metabolism; D005109:Extracellular Matrix / Q000502:physiology; D037181:Lectins, C-Type / Q000172:deficiency*; D018878:Limb Buds / Q000196:embryology*; D008648:Mesoderm / Q000502:physiology; D051379:Mice; D008822:Mice, Transgenic; D053675:Versicans
D011508:Chondroitin Sulfate Proteoglycans; D024043:Collagen Type II; D037181:Lectins, C-Type; C508323:Vcan protein, mouse; D053675:Versicans