FIG. 4.

ChM-I mRNA expression in bone. The top panel shows the ChM-I transcripts. The bottom panel shows glyceraldehydes-3-phosphate dehydrogenase (GAPDH) transcripts. Primary calvarial osteoblasts from newborn wild-type mice were cultured as described in Materials and Methods. Bones from wild-type 12-week-old mice were prepared as described in Materials and Methods. Osteoclasts were purified from coculture bone marrow cells with calvarial osteoblasts. Rib cartilage from 4-week-old wild-type mice was dissected free of adherent soft tissues. Reverse transcription-PCRs performed in the absence of reverse transcriptase (−RT) failed to detect any transcripts (representative lane shown).