Figure 4.

The cAMP/PKA pathway is not implicated in Nf1-related learning deficit within OK72 neurons. Performance assessment after conditioning of control (white bars), mutant (black bars), experimental (dark gray bars), and transgene-overexpressing (light gray bars) animals. The genotypes of all animals are indicated below each bar. Data are mean ± SEM. G80^ts indicates the ubiquitously expressed temperature-sensitive Gal4 repressor Tub-Gal80^ts. A, Expression of a constitutively active Drosophila PKA transgene in OK72 neurons (dark gray bar) does not rescue the dNf1^E2 learning deficit (black bar) relative to controls (white bar). The second and third bars (light gray) represent learning of WT animals expressing the UAS-PKA^C1 transgene in OK72 neurons, including or excluding the MBs, respectively, and are indistinguishable from the control. B, Expression of a constitutively active murine PKA* transgene with 2 (first gray bar) or 4 (second gray bar) UAS elements in OK72 neurons does not reverse the learning deficit of dNf1^E2 mutant homozygotes (black bars). The performance of both null mutants (black bars) and PKA* transgene-expressing mutant animals (gray bars) is significantly different from that of control flies (white bar). C, Pan-neuronal expression, under the Alk-Gal4 driver, of a constitutively active murine PKA* transgene with 2 UAS elements (gray bar) fails to reverse the learning deficiency of dNf1^E2 homozygotes (black bar). D, Expression of a constitutively active murine PKA* transgene with 2 (first gray bar) or 4 (second gray bar) UAS elements in adult MBs does not rescue the learning deficit of dNf1^E2 homozygotes. *Statistically significant difference of the experimental from mutant flies. ^§Statistical difference of the respective experimental group from the mutant flies (p = 0.0277). E, Rolipram administration (1 mm) to dNf1^E2 null homozygotes (gray bar) does not restore learning, which remains indistinguishable from that of untreated mutant flies (black bar). Treated and untreated control flies (white bars) perform significantly different from the mutant groups. Control flies are OK72-Gal4 homozygotes, whereas the genotype of E2 mutants is OK72-Gal4;E2 homozygotes.