(a) IHC staining in P14 coronal slices reveals strong immunoreactivity in the hippocampus and PFC (delineated by white dotted lines). MET protein expression in the hippocampus and PFC was probed by Western blot analysis at E17.5, P3, P11 and P21. (b) Quantification of a. Peak expression of MET protein (normalized to GAPDH levels) occurs around P3-11, and declines precipitously thereafter. (c) Expression levels of the MET receptor ligand, HGF, and molecules potentially mediating downstream signaling events (Gab1, Grb2, Cdc42, Rac1 and PI3K/P85) (n = 2). (d) Western blot analysis (n = 3) and immunocytochemistry staining of MET protein in cultured low-density hippocampal neurons during in vitro development. (e) High resolution confocal imaging reveals strong MET immunoreactivity localized to axon growth cone tip (n = 4 experiments). (f) Diagram depicting isolation of growth cone fractions from P0 mouse brain. (g) Western blot analysis of MET reveals enriched protein levels at the growth cone, similar to other proteins known to be concentrated in growth cones (p-Tau, GAP43, Cdc42 and FAK) during early neuronal development (n = 3, quantification not shown).