It has been more than 20 years since scientists discovered that mutations in the gene huntingtin cause the devastating progressive neurological condition Huntington's disease, which involves involuntary movements, emotional disturbance and cognitive impairment. Surprisingly little, however, has been known about the gene's role in normal brain activity.
Now, a study from The Scripps Research Institute's (TSRI's) Florida campus and Columbia University shows it plays a critical role in long-term memory.
"We found that huntingtin expression levels are necessary for what is known as long-term synaptic plasticity—the ability of the synapses to grow and change—which is critical to the formation of long-term memory," said TSRI Assistant Professor Sathyanarayanan V. Puthanveettil, who led the study with Nobel laureate Eric Kandel of Columbia University.
In the study, published recently by the journal PLOS ONE, the team identified an equivalent of the human huntingtin protein in the marine snail Aplysia, a widely used animal model in genetic studies, and found that, just like its human counterpart, the protein in Aplysia is widely expressed in neurons throughout the central nervous system.
Using cellular models, the scientists studied what is known as the sensory-to-motor neuron synapse of Aplysia—in this case, gill withdrawal, a defensive move that occurs when the animal is disturbed.
The study found that the expression of messenger RNAs of huntingtin—messenger RNAs are used to produce proteins from instructions coded in genes—is increased by serotonin, a neurotransmitter released during learning in Aplysia. After knocking down production of the huntingtin protein, neurons failed to function normally.
"During the learning, production of the huntingtin mRNAs is increased both in pre- and post-synaptic neurons—that is a new finding," Puthanveettil said. "And if you block production of the protein either in pre- or post-synaptic neuron, you block formation of memory."
The findings could have implications for the development of future treatments of Huntington's disease. While the full biological functions of the huntingtin protein are not yet fully understood, the results caution against a therapeutic approach that attempts to eliminate the protein entirely.
The first author of the study, "Huntingtin Is Critical Both Pre- and Postsynaptically for Long-Term Learning-Related Synaptic Plasticity in Aplysia," is Yun-Beom Choi of Columbia University. Other authors include Beena M. Kadakkuzha, Xin-An Liu and Komolitdin Akhmedov of TSRI. For more information on the study, see http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0103004
The work was supported by the Howard Hughes Medical Institute, the National Institutes of Health (Grant NS053415), the Whitehall Foundation and the State of Florida.
Eric Sauter | Eurek Alert!
Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz
Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences