Enteric neurons
are Ret-dependent
•GDNF binds to GRFa1 and stimulates Ret.
•Mice that lack Ret (or GDNF or GFRa1) lack enteric neurons below the level of the esophagus.
•Loss of function mutations in RET, GDNF, or GFRa1 are associated with Hirschsprung’s disease
Wild-type
Ret -/-