Expression of fraΔC.Scer\UAS.T:Hsap\MYC under the control of Scer\GAL4605 in fra3/fra4 embryos results in abnormal spreading of the dMP2 growth cone over the region of induced ectopic NetB accumulation.
fra3 strongly suppresses the dMP2 axon misprojection phenotype seen in homozygous robo1 embryos, reducing the penetrance of the contralateral misprojection along the anterior commissure of the next segment from 99% to 24%. Expression of fraΔC.Scer\UAS.T:Hsap\MYC under the control of Scer\GAL4insc-Mz1407, but not under the control of Scer\GAL415J2, restores the aberrant midline-crossing phenotype in these animals.
The pCC and vMP2 midline-crossing phenotypes seen in homozygous robo1 embryos are partially and strongly suppressed by fra3 respectively. Expression of fraΔC.Scer\UAS.T:Hsap\MYC under the control of Scer\GAL4605 restores the aberrant midline-crossing phenotype in these animals.