Fig. 6.

Comparison of neurite lengths at different times after adenovirus infection and effects of XAC phosphorylation site mutants. A, Median neurite lengths are shown 1 and 3 d after infection with XAC(wt)- and GFP-expressing adenoviruses at 100 pfu/cell. At 1 d after infection, adXAC(wt)-infected neurons were of similar length to that of adGFP-infected controls. At this time, XAC(wt) levels are still very low in the neurons (see Fig.4). By 3 d after infection, XAC(wt)-expressing neurons have much longer neurites than that of GFP-expressing controls (p < 0.05; t test).B, C, Adenoviral-mediated expression of the constitutively active XAC(A3) mutant increased neurite length but to a lesser extent than XAC(wt). Expression of the inactive XAC(E3) mutant did not affect neurite length. Rat cortical cultures were infected at 150 pfu/ml. A, Results shown are the averages from two independent experiments (error bars indicate range). Median lengths were normalized so that control cultures infected with GFP were at 100%. B, The length distribution shown is from a single experiment. Expression of XAC(wt) increased neurite lengths, as shown by a shift to the right of the length distribution curve compared with neurons expressing XAC(E3). XAC(A3) expression increased the numbers of neurites of intermediate length, but unlike XAC(wt), did not appreciably increase the frequency of longer neurites. At least 150 neurons were analyzed per adenovirus per experiment.