Until now it was not known how a nerve cell knows where it should grow and which cells to contact.
Scientists of the Max Planck Institute of Neurobiology in Martinsried have now shown that growing nerve cells realise when they've reached their target area in the fly brain thanks to the interaction of two genes. Similar mechanisms are also likely to play a role during the development of the vertebrate brain and could thus be important for a better understanding of certain developmental disorders.
For their investigation, the neurobiologists analyzed the function of genes that play a role in the development of the visual system of the fruit fly.he scientists now report that the visual system of the fruit fly is only able to develop correctly, when two genes work together - the genes that are in charge of producing the proteins "Golden Goal" and "Flamingo".
These two proteins are located at the tip of a growing axon, where they are believed to gather information about their environment from the surrounding tissue. The actions of these two proteins enable nerve cells in a number of ways to find their way in the brain and recognize their target area.
The study showed that chaos results if only one of the genes is active, or if there is a mismatch in the genes' activity: the axons cease to grow somewhere along the way and never reach their target area.
"We assume that very similar mechanisms play a role also in other organisms - including humans", explains Takashi Suzuki, lead author of the study.
The study has been published in the scientific journal Nature Neuroscience.