Mice lacking link protein develop dwarfism and craniofacial abnormalities.

摘要: Link protein (LP), an extracellular matrix in cartilage, stabilizes aggregates of aggrecan and hyaluronan, giving cartilage its tensile strength elasticity. Cartilage provides the template for endochondral ossification is crucial determining length width skeleton. During bone formation, hypertrophic chondrocytes die replaced with matrix. Here, we have generated targeted mutations mice gene encoding LP (Crtl1). Homozygotes showed defects development delayed formation short limbs craniofacial anomalies. Most Crtl1(tm1Nid/tm1Nid) died shortly after birth due to respiratory failure, but some survived developed progressive dwarfism lordosis cervical spine. They small epiphysis, slightly flared metaphysis long bones flattened vertebrae, characteristic spondyloepiphyseal dysplasias. The contained significantly reduced depositions zone, decreased numbers prehypertrophic chondrocytes. Reduced Indian hedgehog (Ihh) expression was observed chondrocytes, apoptosis inhibited These results indicate that important proteoglycan normal organization suggest has a role chondrocyte differentiation maturation.