Fig. 6. pak-1 and max-2 are differentially required for commissural axon guidance. Genetic interaction studies on the DD and VD commissural guidance defects in PAK mutants and other mutants in genes that are known to play roles in the unc-6/netrin commissural guidance pathway. (A) Axon guidance defects of rac mutants are greatly enhanced by a loss of max-2 but not by a loss of pak-1. (B) The defects caused by constitutively active rac(GF)s can be suppressed by the loss of pak-1. The asterisk denotes a P-value less than 0.001 (Student's t test). (C) The defects caused by constitutively active rac(GF)s are enhanced by a loss of function in the max-2 gene. The max-2 data was also independently confirmed with dsRNA as in the ced-10(GF) result. (D) max-2(cy2) enhances the defects of mutants from genes that are known to play roles in the unc-6/netrin commissural guidance pathway. The numbers (n) of animals used for each experiment are shown; bars represent the standard error.