Figure 5

Overexpression of Nuak kinases 1 and 2 in primary cortical neurons suggests roles for Nuak Kinase 1 in neurite initiation and dendritic branching. (A) Primary cortical mouse neurons transfected with mRFP at 48 h after re-plating, scale bars 50 µm. (B) One-way ANOVA determined there was no statistically significant difference in length of neurites likely to become dendrites [F(2,234) = 1.904, p = 0.151]. There was no statistically significant difference between Nuak Kinase 1 OE (34.06 ± 1.94, n = 111, p = 0.742) and Nuak Kinase 2 OE (41.56 ± 3.89, n = 79, p = 1.000) as compared to control OE (39.53 ± 3.92, n = 47). (C) One-way ANOVA determined there was no statistically significant difference in length of neurites likely to become axons [F(2,67) = 1.010, p = 0.370]. There was no statistically significant difference between Nuak Kinase 1 OE (255.91 ± 47.27, n = 33, p = 0.500) and Nuak Kinase 2 OE (210.43 ± 33.01, n = 25, p = 1.000) as compared to control OE (179.47 ± 24.55, n = 20). (D) One-way ANOVA determined there was a statistically significant difference [F(2,67) = 6.313, p = 0.003]. Bonferroni post hoc test revealed that mean number of neurites was statistically significantly greater for Nuak Kinase 1 OE (5.5 ± 0.483, n = 25, p = 0.002) as compared to control OE (3.5 ± 0.312, n = 20). There was no statistically significant difference in mean number of neurites between Nuak Kinase 2 OE (4.5 ± 0.327, n = 25, p = 0.233) as compared to control OE (3.5 ± 0.312, n = 20). (E) Sholl analysis shows a dramatic increase in branching complexity in Nuak Kinase 1 overexpressing cells proximally and a slight increase in branching complexity in Nuak Kinase 2 overexpressing cells proximally, with a decrease in branching complexity more distally in both Nuak kinases as compared to control OE. Branching appears to become similar to controls in both experimental groups at the most distal points.