Overexpression of wild type (Wt) and mutant (Mt) TDP-43 mRNA produces motor axonopathies.

<p>A) Anti-V5 immunoblot confirmed similar expression levels of Wt and Mt TDP-43 following TDP-43 mRNA injection. Protein produced by <i>in vitro</i> translation of the Wt TDP-43 mRNA served as a positive control. B) Overexpression of Wt TDP-43 produced modest axonal shortening (∧p<0.001) and aberrant branching (∧p<0.001) in comparison with Buffer injection (n = 61). Mt TDP-43 expression (600 ng/µl: n = 37, 650 ng/µl: n = 64, 700 ng/µl: n = 26) produced a more pronounced effect, resulting in significantly shorter axonal lengths (*p<0.001) and more embryos affected by aberrant branching (*p<0.001) than Wt TDP-43 injected embryos (600 ng/µl: n = 35, 650 ng/µl: n = 59, 700 ng/µl: n = 45).