Cdc42 regulates synaptic OXT levels.(A) Assessment of the effect of Oxytocin neuron-specific overexpression of actin-regulating protein Cdc42 in Tg(oxt:Gal4) larvae. Transgenic embryos expressing the oxt:Gal4 driver were injected with transposon-based transgenic vectors containing either control UAS:EGFP or UAS:Cdc42(G12V)-EGFP coding a constitutive active mutant Cdc42. Larvae were fixed at 8 days post-fertilization (dpf) and immunostained with anti-GFP and anti-OXT antibodies and neurohypophyseal synapse (NS) were identified as described above. (B,C) Linear regression analysis comparing between synaptic EGFP levels (mean EGFP puncta) as a function of OXT fluorescence (mean OXT puncta). The data were normalized using mean-centering approach using the scale function in the ‘R’ software. Each line represents a regression line of single animal. The correlation between the mean (log10) fluorescence value of OXT puncta and GFP expression in neurohypophyseal synapse was tested with a linear regression model (ANCOVA), accounting for the effect of GFP fluorescence, and individual fish. In UAS:EGFP injection, mean EGFP fluorescence in EGFP-positive NS is not correlated with OXT fluorescence (n = 20; and p>0.25, adj. R2 = 0.23) (B). In UAS:Cdc42(G12V) injection, mean EGFP-Cdc42(G12V) fluorescence in EGFP-positive NS negatively correlates with OXT fluorescence (n = 23; p<2.2e-16, adj. R2 = 0.47) larvae (C). Legends for Source data and Source code files.
|