(A-D) Osteospheres from osteoblasts derived from P1 calvaria of wild type mice were collected by straining through a 40 μM strainer and RNA was extracted from the spheres. Gene expression of Sox2 (A), Osterix (B), Runx2 (C), and Collagen1-a1 (D) was analyzed by qRT-PCR using specific primers. All values are normalized to actin as an internal control and are expressed relative to total (adherent) cells in each case. * = p<0.05
(E) Primary calvarial osteoblasts were plated in suspension culture in the presence or absence of 10 ng/ml recombinant FGF1. Spheres were counted after 7 days. * = p<0.05
(F) Primary P1 calvarial osteoblasts from control (Sox2 flox/+;Cre, Sox2flox/- and Sox2flox/+) and cko (Sox2flox/-;Cre) littermates were plated in triplicate in 6 cm Corning ultra-low attachment plates. Total number of osteospheres was counted after 7 days. * = p < 0.05