Figure 5.

Micro-dissection efficiently separates different growth plate zones from cultured tibiae. E15.5 tibiae that were harvested and incubated with or without CNP (1 μM) for six days were micro-dissected into the resting/proliferating, hypertrophic, and mineralized regions as shown (A). Zones from approximately 24 bones were pooled together. RNA was isolated directly from micro-dissected tibia and analyzed by microarray as described in Materials and Methods. Real-time PCR analyses confirmed expected expression patterns of the cartilage markers Col2a1 and Col10a1 in control bones (B; data represent means ± SD from three independent trials). Expression patterns of selected chondrocyte marker genes under control conditions in our microarray data sets further demonstrated efficient separation of regions (C).