How a developmental gene controls feeding behavior

"Animals interact with their environment based on stereotypical movement patterns, such as those performed during running, breathing or feeding," explains Prof. Lohmann, who directs the Developmental Biology research group at the Centre for Organismal Studies. "We have known for some time that a family of regulatory genes known as Hox genes is essential for establishing coordinated movement patterns. But until now we did not understand the molecular underpinnings of feeding behaviour." Using Drosophila melanogaster, Prof. Lohmann's team was able to demonstrate that a specific Hox gene, known as Deformed, controls the establishment of the feeding motor unit not only during the development of the embryo. It is also responsible for maintaining its function in later phases of life, which was revealed when the researchers deactivated Deformed after embryogenesis when the motor unit was successfully formed. Yet the typical movement patterns were lost anyway. The team was able to attribute the loss to major changes at the junctions, or synapses, between the neuron and the muscle.

"Our studies show that Hox genes have a protective function in neurons. As soon as this protection is gone, the neurons degenerate, like we observe in neurodegenerative diseases such as Alzheimer's and Parkinson's," explains Prof. Lohmann. Future studies will be devoted to elucidate how Hox genes perform this protective function at the molecular level. The research project was funded by the German Research Foundation.