Fig. 5.

PDGFRA is not a physiologically important target of Mir140 in mouse chondrocytes. (A) PDGFRA expression is not upregulated in Mir140-null primary chondrocytes. Multiple bands detected by immunoblot analysis using anti-PDGFRA antibody in primary rib chondrocytes (left). The top two bands (arrowhead) migrate at the expected molecular masses (150 and 170 kDa). Pdgfra mRNA expression determined by qRT-PCR was not significantly altered in Mir140-null primary chondrocytes. N.S., not significant. (B) A chondrocyte-specific PDGFRA knockout (cKO) shows mild shortening of the longitudinal length of the skull and long bones. Skeletal preparation of the skull (left) and hind limbs (middle) at P10.5. Mineralization of the talus at P0.5 is slightly advanced in cKO mice (right). (C, D) Conditional ablation of Pdgfra does not rescue the skeletal defect of Mir140-null mice. (C) At P1.5, the shortening of the long bones of Mir140-null mice is not rescued by conditional Pdgfra ablation in chondrocytes. (D) The advanced mineralization of the hyoid horns (arrowheads) of 1.5-day-old Mir140-null mice was even augmented but not rescued in doubly mutant mice.