Inhibition of ERK prevents osteogenic differentiation in cells cultured on CTGF matrix.

<p>Alkaline Phosphatase (ALP) staining of osteoblasts cultured on 1% BSA <b>(A)</b> or 2 μg/ml CTGF coated plates in the absence of ERK inhibitor <b>(B)</b> and in the presence of ERK inhibitor <b>(C)</b> for 14 days. Scale bar = 2 mm. <b>(D)</b> ALP activity of osteoblasts cultured on BSA or CTGF coated plates, quantified at day 14 of culture and normalized to total protein content; n = 9 wells.