Figure 4.
Erk1/2 activation is inversely correlated with P75NTR expression. (A, B) Immunohistochemistry on E12 dissociated ventral midbrain cultures derived from EnHT E12 embryos stained against TH (green) and P75NTR. P75NTR expression is absent in cultures treated with Penetratin-coupled double-stranded RNA oligos. (C) Western blot of ventral midbrain cultures using two methods of RNA transfection with different efficiencies: HiPerfect (HiP) and Penetratin-coupled RNA oligos show increase in phosphorylated Erk1/2 after silencing of P75NTR, but no changes in phosphorylation of P38. (D) Quantification of P75NTR expression and Erk1/2 phosphorylation after transfection with P75NTR double-stranded RNA oligonucleotides, normalized against untreated EnHT cultures, showing the inverse correlation between the two parameters. Scale bars: 25 μm. Error bars indicate standard error.