Figure 8.

Fgf10^creERT2 lineage-traced cells generate neurons in multiple hypothalamic nuclei and can respond to acute fasting. A–G, Immunoperoxidase labeling for NeuN (A–D') or GFAP (E–G) shows that adult lineage traced (Xgal⁺) cells can differentiate into neurons of the arcuate and ventromedial nuclei. Lineage-traced cells do not express GFAP (E–G). H–K, Better visualization of P28 lineage-traced cells through the use of Fgf10^creERT2:R26^tomato line confirms the radial morphology of the recombined tanycytes (long arrows) as well as the elaborate axonal/dendritic arborization (H, short arrows) of their parenchymally located neural descendants, whose neuronal identity is confirmed by NeuN labeling (short arrows in I–K). L–O, An example of a P28 lineage-traced (Tom⁺) arcuate neuron that has responded to fasting and in vivo leptin treatment by expressing phospho-STAT3. Scale bars: A–D, E–H, 75 μm; L, 30 μm; A', B', C', D', I, M, 15 μm.