The present invetion relates to a novel isolated leafhopper ecdysone receptor polypeptide. The invention also realtes to an isolated nucleic acid encoding the leafhopper ecdysone receptor polypeptide, to vectors comprising them and to their uses, in particular in methods for modulating gene eypression in an ecdysone receptor-based gene expression modulation system and methods for identifying molecules that modulate leafhopper ecdysone receptor activity.