Figure 3.

Knockdown of ECM1 enhances chondrocyte differentiation. A) pSuper-ECM1 (siECM1), an ECM1 siRNA construct, reduced >70% of endogenous ECM1 mRNA as measured by real-time PCR. B) siECM1 largely reduces ECM1 protein level detected by cell immunostaining. C–F) Blocking ECM1 expression stimulates chondrocyte marker genes, including Col X (C, E) and Sox9 (D, F), in both C310T1/2 (C, D) and ATDC5 (E, F) cells, assayed by real-time PCR. Experiments were carried out in biologic replicates (n = 3). Units are arbitrary and normalized values were calibrated against controls, here given the value of 1. Rel. level, relative level. Values are means ± sd. *P < 0.05 vs. control group.