<p><b>Copyright information:</b></p><p>Taken from "Inorganic pyrophosphate generation by transforming growth factor-beta-1 is mainly dependent on ANK induction by Ras/Raf-1/extracellular signal-regulated kinase pathways in chondrocytes"</p><p>http://arthritis-research.com/content/9/6/R122</p><p>Arthritis Research & Therapy 2007;9(6):R122-R122.</p><p>Published online 22 Nov 2007</p><p>PMCID:PMC2246241.</p><p></p> Rat chondrocytes were electroporated with empty vector, wild-type, constitutively active, or dominant-negative plasmids for Ras or Raf-1 (2 μg/well of six-well plate) before stimulation with 10 ng/mL of TGF-β1 for 12 hours. Total RNA was extracted and subjected to real-time polymerase chain reaction analysis. The mRNA level of Ank was normalized to that of S29 mRNA and is expressed as mean percentages (± standard deviation) over control values from three independent experiments. Statistically significant differences from the control are indicated as *< 0.05 and from TGF-β1-treated cells as #< 0.05. Effect of TGF-β1 on extracellular signal-regulated kinase (ERK) 1/2 phosphorylation in electroporated cells with wild-type, constitutively active, or dominant-negative plasmids for Ras (2 μg/well of six-well plate). Total proteins were extracted from rat chondrocytes exposed to 10 ng/mL of TGF-β1 for 15 minutes and subjected to Western blotting using anti-phospho- and anti-total-ERK 1/2 antibodies. The relative abundance of these proteins was normalized to that of β-actin protein
