Electrical synapses connect nerve cells in nearly all brains; nevertheless, little is understood about them. “Electrical synapses are like the dark matter of the brain,” says Alexander Borst, director at the MPI for Biological Intelligence, in foundation (i.f). Now a team from his department has actually taken a closer look at this hardly ever explored brain element: In the brain of the fruit fly Drosophila, they were able to reveal that electrical synapses occur in practically all brain areas and can affect the function and stability of individual nerve cells.
In the brain of fruit flies, they were thus able to reveal that electrical synapses do not take place in all nerve cells, but in almost all locations of the brain.” The outcomes suggest that electrical synapses are crucial for varied brain functions and can play very different functional roles, depending on the type of nerve cell,” Ammer summarizes.
Electrical synapses connect nerve cells in almost all brains; nevertheless, little is learnt about them. A study now shows for the first time where these specific synapses happen in the fruit fly brain which they affect the function and stability of afferent neuron. Credit: MPI for Biological Intelligence, i.f./ Julia Kuhl
Electrical synapses– omnipresent and yet hardly explored.
They are part of the brain of nearly every animal species, yet they remain typically undetectable even under the electron microscope. “Electrical synapses resemble the dark matter of the brain,” says Alexander Borst, director at the MPI for Biological Intelligence, in foundation (i.f). Now a group from his department has actually taken a better take a look at this rarely explored brain component: In the brain of the fruit fly Drosophila, they were able to show that electrical synapses take place in nearly all brain areas and can affect the function and stability of specific nerve cells.
Nerve cells communicate via synapses, small contact points at which chemical messengers send a stimulus from one cell to the next. We might remember this from biology class. Nevertheless, that is not the entire story. In addition to the typically recognized chemical synapses, there is a second, obscure type of synapse: the electrical synapse. “Electrical synapses are much rarer and are tough to spot with existing techniques. Thats why they have actually hardly been researched so far,” explains Georg Ammer, who has long been amazed by these hidden cell connections. “In the majority of animal brains, we therefore do not know even basic things, such as where precisely electrical synapses occur or how they influence brain activity.”.
An electrical synapse connects two nerve cells straight, enabling the electrical current that nerve cells utilize to interact, to flow from one cell to the next without a detour. Other than in echinoderms, this specific kind of synapse occurs in the brain of every animal types studied up until now. “Electrical synapses must for that reason have crucial functions: we simply do not know which ones!” states Georg Ammer.
Distribution in the brain.
In the brain of fruit flies, they were hence able to show that electrical synapses do not take place in all nerve cells, but in practically all locations of the brain. By selectively switching off the electrical synapses in the area of visual processing, the scientists could show that the impacted nerve cells response to particular stimuli is much weaker.
” The outcomes suggest that electrical synapses are crucial for varied brain functions and can play very different functional functions, depending on the type of neuron,” Ammer summarizes. How these can be incorporated into connectome investigations and what other tricks electrical synapses hold, is subject for more research studies.
Referral: “Anatomical distribution and functional functions of electrical synapses in Drosophila” by Georg Ammer, Renée M. Vieira, Sandra Fendl and Alexander Borst, 5 April 2022, Current Biology.DOI: 10.1016/ j.cub.2022.03.040.
