Functional connections with foreign muscles made by a target-deprived insect motorneuron.

Metathoracic limb buds were removed unilaterally from Locusta migratoria embryos at 30% of embryonic development, thereby depriving limb-innervating neurons of the opportunity of innervating their normal target muscles. The operated embryos were allowed to hatch and develop to adulthood, and then the connections between the identified limb motorneuron Fast Extensor Tibiae (FETi) and body wall muscles on the operated side of the segment were determined electrophysiologically. FETi innervated a number of foreign muscles in the ipsilateral body wall in limb-ablated locusts, showing that this neuron is not programmed to exclusively innervate its normal target muscle.