We have established that the Hox transcription factors Deformed (Dfd) is critically required for feeding behavior, importantly for the establishment of the stereotypic feeding movements.
Movie of a Drosophila larva extensively moving its head with the associated mouth hooks, which are required for hatching and feeding.
Using genetic, molecular, genomic and behavioral approaches we have demonstrated that Dfd is required throughout the formation of the feeding unit by directly controlling neuronal specification, axon outgrowth, synapse formation and genes with roles in neurotransmission. Importantly we have found the expression of the Dfd target Ankyrin2-XL to be reduced and synapse architecture to be changed after late interference with Dfd activity, demonstrating that the microtubule-organizing complex required for synaptic stability and connectivity is under direct Hox control.
Muscle bundles (red) associated with different parts of the feeding apparatus are innervated by Dfd positive motoneurons (green) to allow synaptic transmission and feeding movements. Functional synapses are labelled with DVGlut (blue).
We now use this system to study on the one hand how Hox TFs control the communication and interaction of motoneurons with their target muscles, which is critical for the establishment of region-specific motor units and thus for coordinated movements. On the other hand, we aim to understand how Hox TFs execute their neuro-protective function we have uncovered, which is relevant in the context neuro-degenerative diseases and ageing.