Researchers have discovered a pathway by which the brain controls a molecule critical to forming long-term memories and connected with bipolar disorder and schizophrenia.
The discovery was made by a team of scientists led by Alexei Morozov, an assistant professor at the Virginia Tech Carilion Research Institute.
The mechanism – a protein called Rap1 – controls L-type calcium channels, which participate in the formation of long-term memories. Previous studies have also linked alterations in these ion channels to certain psychiatric disorders. The discovery of the channels' regulation by Rap1 could help scientists understand the physiological genesis of bipolar disorder and schizophrenia.
"People with genetic mutations affecting L-type calcium channels have higher rates of bipolar disorder and schizophrenia," said Morozov. "This suggests that there might be a relationship between the activation of L-type calcium channels and these psychiatric disorders. Understanding how these ion channels are controlled is the first step to determining how their functioning or malfunctioning affects mental health."
A single neuron in the brain can have thousands of synapses, each of which can grow, strengthen, weaken, and change structurally in response to learning new information. Electric signals traveling from neuron to neuron jump across these synapses through chemical neurotransmitters. The release of these chemicals is caused by the flow of electrically charged atoms through a particular subset of ion channels known as voltage-gated calcium channels.
Previous studies have shown that blocking these ion channels inhibits the formation of long-term memories. Although it was known that L-type calcium channels are activated in response to learning, how they are controlled was a mystery.
In the experiment, Morozov and colleagues knocked out the gene responsible for coding the enzyme Rap1, which he suspected played a role in activating L-type calcium channels. The researchers then used live imaging techniques to monitor the release of neurotransmitters and electron microscopy to visualize L-type channels at synapses. They discovered that, without Rap1, the L-type calcium channels were more active and more abundant at synapses all the time, increasing the release of neurotransmitters. The results showed that Rap1 is responsible for suppressing L-type calcium channels, allowing them to activate only at the proper moments, possibly during long-term memory formation.
"Our next step is to determine whether this new signaling pathway is altered in cases of mental disease," said Morozov. "If so, it could help us gain a better understanding of the molecular underpinnings of channel-related psychiatric disorders, such as bipolar disorder and schizophrenia. Such knowledge would go a long way toward developing new therapeutic methods."
The discovery appeared in The Journal of Neuroscience in the study "Rap1 Signaling Prevents L-Type Calcium Channel-Dependent Neurotransmitter Release," by Jaichandar Subramanian, now a research fellow at the Picower Institute for Learning and Memory at the Massachusetts Institute of Technology; Louis Dye, a staff scientist at the Microscopy and Imaging Core of the National Institute of Child Health and Human Development; and Morozov, who is also an assistant professor in Virginia Tech's School of Biomedical Engineering and Sciences.
Written by Ken Kingery
Paula Byron | EurekAlert!
Antarctic Ice Sheet mass loss has increased
14.06.2018 | Technische Universität Dresden
WAKE-UP provides new treatment option for stroke patients | International study led by UKE
17.05.2018 | Universitätsklinikum Hamburg-Eppendorf
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
21.06.2018 | Life Sciences
21.06.2018 | Earth Sciences
21.06.2018 | Life Sciences