.png)
The drd mutant fly as a model for neurodegenerative disease
Normally, all neurons in the fly brain are surrounded by the processes of cells called cortex glia. In the brains of drd mutant flies, some cortex glia degenerate, leaving neurons “unwrapped”. As a result, mutant flies undergo profound neurodegeneration and die after only a week of adult life. The images show a section of adult fly brain, with nuclei in blue and cortex glia in red. In the control brain (top), all cells are surrounded by cortex glial processes, but in the mutant (bottom), the cortex glial network has broken down. What causes the cortex glia to die? How does the brain respond?
Sructure and function of the drd mutant gut
Entry of food into the fly’s midgut is controlled by a structure called the cardia. In drd mutant flies, the cardia is misshapen and fails to produce an important structure called the peritrophic membrane. The image shows two control cardias with nuclei in blue and the peritrophic membrane in yellow. How does this impact food movement through the digestive tract and the composition of the microbes (the microbiome) that live in the gut?
Effect of drd on adult body mass
The growth of insect larvae and the timing of their development is precisely controlled to produce normal sized adults. Flies that lack drd in their respiratory systems grow slowly and are too small as adults. What regulatory pathways are affected by the drop-dead gene?