Distinct roles of Smad pathways and p38 pathways in cartilage-specific gene expression in synovial fibroblasts
J. Clin. Invest. Hiroaki Seto, et al. 113:718 doi:10.1172/JCI19899 [Go to this article.]

Figure 2
Effects of ALK3^CA, ALK5^CA, and ALK6^CA expression on chondrocyte-specific gene expression in SFs. (A–E) Gene expression in SFs, as determined by Northern blot analysis (A) and real-time PCR analysis (B–E). Subconfluent monolayer SF cultures were infected with adenovirus vectors and they were then subjected to pellet culture 24 hours after viral infection; mRNA extracted from the pellets after 7 days of culture was then analyzed. Expression of type II collagen (Col II) and aggrecan was clearly induced in ALK3^CA-expressing cultures, as shown by Northern blot analysis (A) and real-time PCR analysis (B and C); this was suppressed by Smad6 coexpression and SB203580 (B and C). Expression of type II collagen and aggrecan was also observed in ALK6^CA-expressing cultures, albeit less efficiently, as shown in B and C by real-time PCR. Neither the osteocalcin nor the osteopontin gene was induced by ALK3^CA virus infection (D and E). P.C., positive control, which represents the Northern blotting using mRNA of primary chondrocytes. N.S., not significant; *P < 0.001; **P < 0.005 (significantly different).