Nef stimulates proliferation of glomerular podocytes through activation of Src-dependent Stat3 and MAPK1,2 pathways
J. Clin. Invest. John Cijiang He, et al. 114:643 doi:10.1172/JCI21004 [Go to this article.]

Figure 4
Role of Src activation in Nef-induced MAPK1,2 and Stat3 phosphorylation and phenotypic changes in podocytes. Control vector–infected (Vector) or Nef-infected (Nef) podocytes were transfected with Src-DN and then selected with hygromycin B. (A) Differentiation was induced at 37°C for 10 days, and then cells were lysed for Western blot for cyclin E, phospho-Stat3, phospho-MAPK1,2, and β-actin. Densitometric data: cyclin E/β-actin ratio: V = 0.15 ± 0.04, V + Src-DN = 0.07 ± 0.03, Nef = 1.57 ± 0.17, Nef + Src-DN = 0.62 ± 0.12; phospho-Stat3/β-actin ratio: V = 0.23 ± 0.06, V + Src-DN = 0.21 ± 0.10, Nef = 0.99 ± 0.18, Nef + Src-DN = 0.30 ± 0.20; phospho-MAPK1,2/β-actin ratio: V = 2.01 ± 0.20, V + Src-DN = 1.83 ± 0.17, Nef = 4.23 ± 0.87, Nef + Src-DN = 1.60 ± 0.26; P < 0.01 when Nef is compared with Nef + Src-DN, n = 3. (B) Total RNA was extracted for Northern blot for synaptopodin (Synap) and GAPDH. Densitometric data: synaptopodin/GAPDH ratio: V = 1.12 ± 0.11, V + Src-DN = 1.34 ± 0.11, Nef = 0.25 ± 0.10, Nef + Src-DN = 1.11 ± 0.14, P < 0.01 when Nef is compared with Nef + Src-DN, n = 3. (C) Simultaneously, cells were divided into 24-well dishes at 20,000 cells per well, and cell number was counted at days 3 and 5. Means of 3 experiments in triplicate are shown. *P < 0.001 as compared with Nef + Src-DN.