Fall 2013 Colloquium: Leslie Pick

Post by Erik Bergmann

In last week’s blog post we looked into how small leaf-tying caterpillars have disproportionate impacts on other arthropod species by modifying their environment.  In this week’s colloquium, the new Chair of the Department of Entomology, Dr. Leslie Pick, spoke about her research using another small insect, the humble fruit fly (Drosophilla malanogaster). This fly punches far above its weight class due to its use as a tool to conduct research in the fields of genetics, evolutionary and developmental biology, and even human medical research.

Dr. Pick explained that Drosophila essentially is a lab rat, or a model organism.  This fruit fly is so highly studied, providing detailed knowledge of the fruit fly’s genetics and development, that it can be used to understand phenomena in research on completely different organisms, like humans.  Model organisms are an essential tool for scientists to conduct research that would otherwise be very difficult or impossible with more complex creatures.

Above: Difference in size between a normal (left) and diabetic (right) Drosophilla melanogaster: Zhang et al. (2009) Proc. Natl. Acad. Sci. USA

Dr. Pick and her students were able to identify sections of the fruit fly genome that control insulin and its function regulating sugar levels in their blood.  By deleting different combinations of 5 peptides in the fly’s DNA that help with the uptake of sugar, Dr. Pick’s lab found a system that mimics diabetes in humans.  They discovered that removal of these peptides didn’t cause instant death of the flies, as it would have in a mammalian species.  Instead, they observed a drop in fly body fat, a drop in fertility, delayed development, and an increase in their blood sugar levels. Essentially, the removal of these insulin-like proteins causes the flies to be diabetic and proved that these fruit flies could be a potential model organism for diabetes research!

Using this information, Pick’s group genetically modified flies with human genes that help to regulate insulin and sugar levels in human blood when fed a diet with varying levels of sugar. Surprisingly, the flies proved to be incredibly resilient and there was a high degree of conservation in maintaining constant levels of sugar in their blood.    

This is only the tip of the iceberg on this work with diabetic flies and Dr. Pick’s research. Want to know more about Dr. Pick, her lab, and their research?  Click HERE to check it out!

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Erik Bergmann is a 3rd year MS student studying the feeding patterns of the brown marmorated stink bug, an invasive pest species now found nationwide, on woody ornamental plant species.