Fig. 2 |. Conversion of astrocytes to functional neurons in vitro and in mouse brain.

a.b, Mouse cortical astrocytes (a) treated with shCtrl or shPTB lentivirus, stained for Tuj1 (red) and MAP2 (green). Scale bar: 80 μm. Right: quantified results (n= 5 biological repeats). Error bars: SEM. Electrophysiological recordings (b), showing repetitive action potentials (top left), large currents of voltage-dependent sodium and potassium channels (top right), and spontaneous post-synaptic currents after co-culture with rat astrocytes (bottom). Indicated in each panel is the number of cells that showed the recorded activity versus the number of cells examined.

c,d, Design of the AAV-shPTB vector (c). AAV-Empty: same vector without shPTB. Schematic of the midbrain section for immunochemical analysis in the indicated panels (d).

e,f, Gradual conversion of midbrain astrocytes to NeuN+ neurons (e). Shown are representative images (Scale bar: 50 μm) at 3 time points and quantified RFP+ cells that showed positive staining for NeuN (left), DDC (middle), and TH (right). n=3 biological repeats (f). Error bars: SEM.

g, Converted TH+ DA neurons marked by Girk2 or Calbindin. Scale bar: 20 μm. Bottom right: Quantified results were based on 3 mice. Error bars: SEM.

h, Electrophysiological recordings on brain slices showing large currents of voltage-dependent sodium and potassium channels (top, left), spontaneous post-synaptic currents (top, right), repetitive action potentials (bottom, left), and mature DA neuron-associated HCN channel activities, specifically blocked with 2 mM CsCl (bottom, right). Indicated in each panel is the number of cells that showed the recorded activity versus the number of cells examined.