Ecdysteroid receptor signaling disruption obstructs blastemal cell proliferation during limb regeneration in the fiddler crab, Uca pugilator

► Ecdysteroid receptor dsRNA injection led to a sustained decrease in EcR/RXR mRNAs. ► Knockdown disrupts blastema cell proliferation, and organization of limb primordia. ► A decrease in circulating ecdysteroid titer is also observed in injected animals. ► Hormone titers rise at late premolt, although injected animals fail to molt. ► RNAi can be an effective tool to dissect ecdysteroid-mediated signaling pathways.