Fig. 2. Increased OP migration in the optic nerve of homozygous TN-C-deficient mice when compared with heterozygous littermates. OP migration analysis was performed as shown for Fig. 1. Data were obtained from experiments at both P0 and P2, with three heterozygous and four homozygous null animals with a C57Bl6J/CBA background and from an experiment at P2 with three heterozygous and three homozygous null animals with a 129 background. At both P0 or P2, more PDGFR mRNA-positive cells were found in each segments of the optic nerves of homozygous TN-C-deficient mice when compared with heterozygous littermates (Student’s t test: *P<0.05, **P<0.01, ***P<0.001).