Pharmacologically inhibiting PAK1 activity decreases myelin gene expression. A, pPAK1/2 is decreased in C6 cells after 30 min of treatment with PAK inhibitors. B, Quantification of pPAK1/2 expression after addition of PAK inhibitors. n = 3 experiments. **p = 0.0031 (ANOVA with Dunnett's multiple comparisons test). C, Myelin mRNAS (mbp, 36k, and mpz) were quantified after treatment of zebrafish from 2 to 4 dpf with DMSO vehicle control or PAK inhibitors, FRAX486, NVS PAK1 1, or G5555 in EM. Each zebrafish sample was a group of 20 fish/treatment. Drugs were refreshed daily. Mbp: F(3,10) = 2.478; 36k: F(3,9) = 4.403; mpz: F(3,9) = 2.539. *p < 0.05. n = 3-5 biological replicates/treatment.