Figure 5. Overexpression of VGF rescues layer 4 formation in thalamocortical axon (TCA)-ablated mice.

(A) Schematic representation of the experimental procedure. (B) P7 electroporated (e.p.) brain showing the DsRed-positive e.p. region in the right hemisphere. (C) Cross-sections of S1 cortices of control, TCA-ablated, and TCA-ablated + e.p. mice stained for DsRed and RORβ. (D) Quantitative analysis of RORβ-expressing cells. Data are presented as a percentage of control (mean ± standard error of the mean [SEM]): TCA-ablated, 75.61 ± 2.87%, p = 0.0028; TCA-ablated + e.p., 99.52 ± 4.54%, p = 0.0022, N = 6 animals for each; Mann–Whitney U test, **p < 0.01. (E) Results of single electroporation of NRN1 or VGF into layer 4 of TCA-ablated mice. The number of RORβ-expressing cells was counted and presented as a percentage of control (mean ± SEM): NRN1 e.p., 72.27 ± 3.68% (TCA-ablated), p = 0.0075, 76.87 ± 2.18% (TCA-ablated +e.p.), p = 0.5476, N = 5 animals for each; VGF e.p., 73.43 ± 4.91% (TCA-ablated, N = 5 animals for control, 7 animals for TCA-ablated), p = 0.0042, 96.2 ± 3.10% (TCA-ablated + e.p., N = 5 animals for control, 7 animals for TCA-ablated), p = 0.0023; Mann–Whitney U test, **p < 0.01. L4, layer 4. Scale bars, 1 mm (B), 100 μm (C).

Figure 5—figure supplement 1. Expression of exogenous NRN1 and VGF in the electroporated cortices.

Coronal sections of P7 cortices electroporated with Nrn1-Flag, Vgf-Fc, and DsRed at E14.3, stained with anti-FLAG (A) and anti-VGF (B) antibodies in thalamocortical axon (TCA)-ablated mice. Note that both signals are observed in layer 4 neurons in the electroporated side but not in the control side. L4, layer 4. Scale bar, 200 μm.

Figure 5—figure supplement 2. Overexpression of NRN1 and VGF did not affect layer 4 formation in control mice.

(A) P7 electroporated brain showing DsRed signal in the right hemisphere. (B) Cross-sections of S1 cortices of control and control + electroporated (e.p.) mice stained for DsRed and RORβ. (C) Quantification of the results. The number of RORβ-expressing cells is presented as a percentage of control (mean ± standard error of the mean [SEM]): 97.54 ± 4.31%, N = 6 for each, p = 0.932; Mann–Whitney U test. L4, layer 4. Scale bars, 1 mm (A), 100 μm (B).