Fig. 4: Increased expression of Kapβ2 does not affect neuronal viability.

a Left: Confocal imaging of primary neurons transfected with GFP-Kapβ2. Arrows indicate cytoplasmic puncta. Green is GFP, and blue is DAPI. Scale bar = 5 μm. Center: Imaris 3D rendering of GFP-Kapβ2 expression in primary rat cortical neurons. Right: Magnification of Imaris’ rendering of GFP-Kapβ2 puncta around the nucleus. Scale bar = 3 μm. b Probability of neuronal death via a cumulative risk of death plot of rat primary cortical neurons transfected with 200/400 ng of Tm⁺/ GFP-Kapβ2⁺ (GFP used as control) per 150,000 cells. Neurons double positive Tm⁺/GFP⁺ were counted (n = 3 biological replicates, m > 150 neurons, Log-rank Mantel-Cox test: n.s. not significant). c Representative images of neurons over time transfected with 200/400 ng of Tm⁺/GFP⁺. Green is Kapβ2; red is Td-Tomato. Scale bar = 20 μm. d Probability of neuronal death via a cumulative risk of death plot of rat primary cortical neurons transfected with 400/400 ng of GFP-Kapβ2 (GFP alone used as control) and GR₅₀-mCherry (mCherry alone used as control) per 150,000 cells. Neurons double positive GFP⁺/mCherry⁺ were counted (n = 3 biological replicates, m > 150 neurons, Log-rank Mantel-Cox test: mCherry vs GR₅₀-mCherry p < 0.0001; GR₅₀-mCherry vs GR₅₀-mCherry /GFP-Kapβ2 p < 0.0001). Inset: bar graph showing quantification of GR₅₀-mCherry and GR₅₀-mCherry /GFP-Kapβ2 overall survival normalized to mCherry 7 days post-transfection, n = 3 biological replicates. Data are represented as mean ± S.E.M. e Probability of neuronal death via a cumulative risk of death plot of rat primary cortical neurons transfected with 400/400 ng of GFP-Kapβ2⁺ (GFP alone used as control) and GR₁₀₀-mCherry (mCherry alone used as control) per 150,000 cells. Neurons double positive GFP⁺/mCherry⁺ were counted (n = 3 biological replicates, m > 150 neurons, Log-rank Mantel-Cox test: mCherry vs GR₁₀₀-mCherry p < 0.0001; GR₁₀₀-mCherry vs GR₁₀₀-mCherry/Kapβ2 p = 0.005). Inset: bar graph showing quantification of GR₁₀₀-mCherry and GR₁₀₀-mCherry /GFP-Kapβ2 overall survival normalized to mCherry at 7 days post-transfection, n = 3 biological replicates. Data are represented as mean ± S.E.M.