PakGMR.T:Myr1 exhibits a dose-dependent dominant phenotype. Wild type larvae carrying a single copy of PakGMR.T:Myr1 show mild clumping of axons in the lamina cortex. The R8 projections in the medulla and the pattern of R cells in the eye disc are normal. This defect is slightly enhanced in animals with two copies of PakGMR.T:Myr1. In larvae carrying four copies of PakGMR.T:Myr1, the R cell projection pattern is severely disrupted. In addition, the pattern of R cell clusters in the eye disc are highly abnormal; in these animals R cells delaminate from the eye disc epithelium and migrate through the optic stalk into the brain. Some cell bodies migrate as far as the medulla.
PakGMR.Tag:Myr(Src64B) is a suppressor of photoreceptor cell & axon phenotype of dockunspecified
PakGMR.Tag:Myr(Src64B) is a suppressor of lamina phenotype of dockunspecified
PakGMR.Tag:Myr(Src64B) is a suppressor of medulla phenotype of dockunspecified
One copy of PakGMR.T:Myr1 in dockunspecified larvae, suppresses the dock phenotype of gaps in the lamina, abnormal axon bundling and unexpanded growth cones in the medulla. Quantification of the expanded growth cones in the medulla showed an increase from less than 2 to 64+/-8 (136+/-12 in wild-type).
A single copy of PakGMR.T:Myr1 rescues the Pak mutant phenotype.