A new device that tracks tiny fruit flies can unlock the mystery of how mutations associated with the development of diabetes affect the production and secretion of the vital hormone insulin.
Researchers at Stanford University have developed a new technique that allows them to measure insulin levels in the insects with extremely high sensitivity and reproducibility.
Developed by research associate Sangbin Park, the new technique uses a chemical tag to label an insulin-like peptide called Ilp2 in fruit flies.
The tag allows researchers to use an antibody-based assay to measure insulin concentrations in the insect's blood and cells at the picomolar level - the level at which insulin concentrations are measured in humans.
Using the technique, researchers were able to quickly identify what a mutation associated with type-2 diabetes in humans actually does: It regulates insulin secretion but not production.
"Many of the genes we studied seem to have similar functions in governing insulin production or secretion in flies and in humans," Park said.
"Studies of diabetes in fruit flies represent a relatively new area of investigation. Needless to say, fruit flies are very small and only tiny amounts of blood can be extracted from their bodies," added Carl Thummel, a professor of human genetics at University of Utah's school of medicine.
For co-researcher Seung Kim, a professor of developmental biology at Stanford University, the new technique is a a true breakthrough.
"Only in selected mammals can researchers measure insulin with this degree of sensitivity," he added.
Until now, scientists wishing to study the effect of specific mutations on insulin had to rely on expensive genetic engineering of laboratory mice or other mammals.
In contrast, tiny, short-lived fruit flies can be bred in dizzying combinations by the tens of thousands in just days or weeks in small flasks on a laboratory bench, researchers said in a paper published in the journal PLOS Genetics.
