At the University of Duke, scientists have been working with fruit flies to try and discover how nerves develop, and they may have had a breakthrough in puzzling together how flies develop neurons that regulate their keen sense of smell.
Image from Wikimedia Commons
Biologist Pelin Volkin and his colleagues at Duke University have been studying fruit flies neurons and how the develop from birth to try and discover how nervous systems in all animals and humans develop, and how they create such a vast array of cell types from a small number of genes. Biologists used fruit flies in this experiment to study how the olfactory neurons, which tell the fly which food is good or bad or if they are in danger, in their antennae differentiate into so many types. Fruit flies have roughly more than 2000 of these olfactory neurons, which differentiate into 50 different types to send messages to the brain.
It was unknown exactly how nervous system precursor genes, which all have identical DNA, differentiated into such a wide variety of olfactory neurons. The biologists hypothesized that alternative splicing played a large role in producing the many different necessary proteins, but they also found that fruit flies used “combinatorial coding”, or recombining genes in different patterns. By regulating which control genes were turned off and on during fruit flies’ development and counting how many different neuron types arose, they were able to identify five genes that work as control switches for developing precursor genes into their respective olfactory neurons for taste and smell.
They have used these findings to compare and find similar counterparts in humans, suggesting the same basic system could be at work for building the nervous system in all organisms.