Figure 6

Oncogenic KRAS expression in CNS increases mitotic activity in the spinal cords. (A, B) 120hpf larvae from an inducible Tg(gfap:rtTA:mCherryKRAS ^G12V) line showed heart edema (arrow), body curvature, and hyperpigmentation of the trunk. At 72hpf, wild-type larvae showed prominent expression of GFAP in the spinal cord (C), and few cells were undergoing mitosis (D). Expression of oncogenic KRAS disrupted the normal GFAP expression pattern in the spinal cord (E), and significantly increased the number of cells undergoing mitosis (F, arrows). SC, spinal cord. Scale bars, 250 μm.