(D-F) Upper panels: Immunoblots of smooth muscle markers, phosphorylated Smad2 (p-Smad2), and TGFR1 expression in control and FRS2 knockdown HASMCs treated with SB431542 (10 m), TGFR2 or Smad2 shRNA lentiviruses. Blots are representative of three independent experiments. Bottom panels: Band intensities of SM-calponin and p-Smad2 were normalized to -tubulin, HSP90, or Smad2 and expressed as a fraction of a control value. 