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LG's Woo Jong Lee Named the Alumnus of College of Engineering
The College of Engineering at KAIST selected Woo Jong Lee, President and Head of the VC Business Division at LG Electronics Inc., as the 2017 Alumnus of the Year for the College of Engineering.
‘Alumnus of the Year’ is an award given to a distinguished alumnus who has contributed to the development of industrial technology or made outstanding academic achievements.
Lee graduated from KAIST with the master’s degrees in Industrial Engineering. He also worked at Daewoo Motors as an executive member in the development division. He has been a crucial human resource for LG since he joined the company in 2000.
While leading the VC business Division, which was established in 2013, Lee is recognized as a creative engineer as well as a leader in the automotive industry. Focusing on autonomous driving and eco-friendliness, he has been engaged in the production of major projects from the beginning to the end.
Since 2014, outstanding alumni whose achievements have represented KAIST at the highest level have received the award. The first recipient was Tae-Kyung Yoo, an executive at Lumens Co., Ltd., and the second recipient was Jung-Ju Kim, the founder of NXC. In 2016, the award was not given because an appropriate candidate could not be identified.
The award was held in the Industrial Engineering & Management Building (E2) on November 8. Faculty members including the dean of the College of Engineering Jong-Hwan Kim, the vice dean Hyochoong Bang, the head of Industrial & Systems Engineering Taesik Lee, and the dean of the KAIST Academy Tae-Eog Lee attended the ceremony.
After the ceremony, Lee delivered a lecture on ‘Auto-components Business of LG Electronics’ to KAIST students.
2017.11.09 View 8966 -
Professor Lee's Research Selected as Top 100 National R&D Projects
A research project, led by Research Professor Ju Yong Lee from the KAIST Institute for IT Convergence, was selected as one of the Top 100 National Research and Development Projects 2017.
This research project, titled LTE-A-based Single RF Small Base Station supporting Multiple Streams, developed 300Mbps low power, low complexity and broadband small base station technology that supports 4x4 MIMO (Multiple Input and Multiple Output) by proposing a new antenna structure and a new RF (Radio Frequency) structure based on LTE-A. Professors from the School of Electrical Engineering at KAIST, Dong Ho Cho, Songcheol Hong, and Yong Hoon Lee also collaborated on the project.
The existing heterodyne method of communication systems generates the problems of increasing unit price and system complexity.
In this project, however, Professor Lee directly modulated the baseband signal from the RF stage through an impedance loading-based RF chip. This method was designed to facilitate low power as well as low complexity while supporting broadband service. Based on this, his team developed source technology for RF that can be applied to fourth and even fifth generation networks.
Furthermore, this base station is smallest among the small-cell stations so far, providing an eco-friendly installation environment. It contributes to the market for fifth generation mobile communications by reducing power consumption significantly yet providing high-capacity services.
Professor Lee said, “This technology will contribute to creating a new market and additional jobs because business based on the fifth mobile generation can provide multi-functional services, including multiband. Requiring low power and providing high-capacity services anywhere at any time will enhance national competence and reduce costs for establishing a next generation mobile communication system. It is expected that this technology will help with disseminating mobile communication infrastructure through expanding information and communication system as well as the infrastructure of island areas.”
2017.11.08 View 9431 -
College of Business Honored with the WRDS-SSNR Innovation Award
(Professor Inmoo Lee (far left), Robert Zarazowski (WRDS), Gregg Gordon (SSRN) and Professor Jae Kyu Lee)
The KAIST College of Business received the WRDS (Wharton Research Data Services)-SSNR Innovation Award for the Asia-Pacific region on October 31 during the AACSB Asia-Pacific Conference in Seoul.
The WRDS-SSRN Innovation Award is intended to elevate the visibility of pioneering research across a broad range of financial and economic topics. Three winners are selected annually from across North America, Europe, and the Asia Pacific based on their ability to demonstrate innovation and research excellence.
The award was created through collaboration with SSRN, the world’s leading early-stage research platform and Elsevier, a global information analytics company specializing in science and health. It honors top business schools that produce exceptional data-driven research. A part of the Wharton School of the University of Pennsylvania, WRDS provides global corporations, universities, and regulatory agencies with the thought leadership, data access, and analytics needed to enable impactful research.
The Dean of the College of Business Youngbae Kim, said that KAIST has been taking the lead in responding to global trends, offering many innovative programs such as an MBA for Social Entrepreneurship and the Master Course for Green Growth Management. KAIST already has been selected as the Most Innovative University in the Asia-Pacific Region by Thomson Reuters for the last two years.
Robert Zarazowski, managing director of WRDS said they recognize and support the outstanding achievement taking place at KAIST as well as its commitment to growth and innovation in business education.
2017.11.03 View 7365 -
Scientist of November, Professor Hyung Jin Sung
Professor Hyung Jin Sung from the Department of Mechanical Engineering at KAIST received a ‘Science and Technology Award of the Month’ given by the Ministry of ICT and Science and the National Research Foundation of Korea for November 2017. He developed technology that can exquisitely control a micrometer-scaled liquid drop on a dime-sized lab-on-a-chip. With his work, he was recognized for reinforcing research capability on microfluidics.
Lab-on-a-chip is an emerging experiment and diagnostic technology in the form of a bio-microchip that facilitates complex and various experiments with only a minimal sample size required. This technology draws a lot of attention not only from medical and pharmaceutical areas, but also the health and environmental field. The biggest problem was that technology for the temperature control of a fluid sample, which is one of the core technologies in microfluidics, has low accuracy. This limit had to be overcome in order to use the lab-on-a-chip more widely.
Professor Sung developed an acoustic and thermal method which controls the temperature of a droplet quickly and meticulously by using sound and energy. This is a thermal method that uses heat generated during the absorption of an acoustic wave into viscoelastic substances. It facilitates a rapid heating rate and spatial-temporal temperature control, allowing heating in desired areas. In addition, Professor Sung applied his technology to polymerase chain reactions, which are used to amplify DNA.
Through this experiment, he successfully shortened the reaction time from 1-2 hours to only three minutes, making this a groundbreaking achievement.
Professor Sung said, “My research is significant for enhancing the applicability of microfluidics. I expect that it will lead to technological innovations in healthcare fields including biochemistry, medical checkups, and new medicine development.”
2017.11.03 View 10315 -
High-Speed Motion Core Technology for Magnetic Memory
(Professor Kab-Jin Kim of the Department of Physics)
A joint research team led by Professor Kab-Jin Kim of the Department of Physics, KAIST and Professor Kyung-Jin Lee at Korea University developed technology to dramatically enhance the speed of next generation domain wall-based magnetic memory. This research was published online in Nature Materials on September 25.
Currently-used memory materials, D-RAM and S-RAM, are fast but volatile, leading to memory loss when the power is switched off. Flash memory is non-volatile but slow, while hard disk drives (HDD) have greater storage but are high in energy usage and weak in physical shock tolerance.
To overcome the limitations of existing memory materials, ‘domain wall-based, magnetic memory’ is being researched. The core mechanism of domain wall magnetic memory is the movement of a domain wall by the current. Non-volatility is secured by using magnetic nanowires and the lack of mechanical rotation reduced power usage. This is a new form of high density, low power next-generation memory.
However, previous studies showed the speed limit of domain wall memory to be hundreds m/s at maximum due to the ‘Walker breakdown phenomenon’, which refers to velocity breakdown from the angular precession of a domain wall. Therefore, there was a need to develop core technology to remove the Walker breakdown phenomenon and increase the speed for the commercialization of domain wall memory.
Most domain wall memory studies used ferromagnetic bodies, which cannot overcome the Walker breakdown phenomenon. The team discovered that the use of ‘ferrimagnetic‘ GdFeCo at certain conditions could overcome the Walker breakdown phenomenon and using this mechanism they could increase domain wall speed to over 2Km/s at room temperature.
Domain wall memory is high-density, low-power, and non-volatile memory. The memory could be the leading next-generation memory with the addition of the high speed property discovered in this research.
Professor Kim said, “This research is significant in discovering a new physical phenomenon at the point at which the angular momentum of a ferrimagnetic body is 0 and it is expected to advance the implementation of next-generation memory in the future.”
This research was funded by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIP) (No. 2017R1C1B2009686, NRF-2016R1A5A1008184) and by the DGIST R&D Program of the Ministry of Science, ICT and Future Planning (17-BT-02).
(Figure 1. Concept Map of Domain Wall Memory Material using Ferrimagnetic Body)
(Figure 2. Scheme and Experimental Results of Domain Wall Speed Measurements)
2017.10.30 View 8896 -
Hanmaeum Education Corps Invites Multicultural Families
About 100 graduates from the Multicultural Mother Schools and their families visited the KAIST campus on October 29 at the invitation of the Hanmaeum Education Corps of KAIST. The Hanmanum Education Corps is a volunteering organization composed of KAIST faculty and students. Many retired KAIST faculties are also members of the corps. Byong Kyu Choi, an Emeritus Professor from the Department of Industrial and Systems Engineering, is the director of the corps and has been leading the event since 2015.
With the support of a KAIST educational volunteering organization called SEED(Social Education Embracing Diversity), this year’s event offered various activities including a treasure hunt and convergent science programs. Participants had the opportunity to experience KAIST’s educational environment and enjoyed the perfect autumn weather during outdoor activities with student volunteers.
Children enjoyed making illumination-music stickers with the KAIST students, even though it was tough to learn at first.
While the children engaged themselves in the science program, parents visited the chrysanthemum fair and some of KAIST’s cafeterias.
Hanmaeum Education Corps opened the Multicultural Mother Schools to support multicultural mothers so that they can have more interest in and help their children more with their education. Since its establishment in 2015, the Multicultural Mother Schools have been expanding throughout the country.
The corporation hopes that visiting a renowned university will encourage children from multicultural families to study hard in addition to offering self-enrichment opportunities through career exploration and science activities.
2017.10.30 View 5326 -
KAIST and KOICA Invited Dominican Republic Officials for Workshop
KAIST will host a two-week workshop for Dominican Republic officials and scholars in collaboration with KOICA (Korea International Cooperation Agency) beginning October 23 at KAIST.
The workshop aims to encourage academia-industry cooperation as one of the Projects for Human Resource Development for Science and Technology at KOICA. Dominican participants including the assistant minister of the Ministry of Higher Education, Science and Technology (MESCYT) and deans of engineering colleges at major universities will enjoy lectures from experts and visit enterprises known for excellent academia-industry collaboration.
According to the Center for Overseas Development, at which Professor WonJoon Kim in the School of Business and Technology Management at KAIST holds the position of director, the workshop is designed to develop human resources in the science and technology (S&T) area, share knowledge on research and development in the field of academia-industry cooperation, and help the participants acquire know-how for managing partnerships between related organizations and industries.
During the workshop, KAIST plans to transfer know-how and share knowledge on its academia-industry cooperation R&D system, in hopes that the workshop will help the Dominican Republic foster its manpower in higher education. The workshop organizers hope that the officers and scholars will be able to apply what they will learn for establishing and carrying out detailed action plans for academia-industry cooperation policies in an effective manner.
“This workshop provides an opportunity to learn about the development of S&T in Korea, academia-industry cooperation R&D, and fostering manpower in advanced S&T. Through the knowledge sharing, we can have a better understanding of academia-industry cooperation as well as education on advanced manpower,” said Pedro Antonio Eduardo, the assistant minister of MESCYT.
He added, “I hope that this workshop will further detailed cooperation between the two countries for Korean high-tech enterprises’ overseas expansion and advanced manpower education. The development model in Korea has many essential elements, so learning its engine for growth and polytechnic manpower education will help develop my country’s industry sector.”
The Project for Human Resource Development for Science and Technology is one of the official development assistance projects running from last year until 2019. It promotes R&D activities for S&T in the Dominican Republic, encouraging academia-industry cooperation by improving trainers in charge of advanced manpower education.
2017.10.30 View 8327 -
Distinguished Professor Lee Named International Fellow of the CAS
Distinguished Professor Sang Yup Lee from the Department of Chemical and Biomolecular Engineering at KAIST was awarded the title of distinguished professor and international fellow from the Chinese Academy of Sciences (CAS), and honorary professor from its affiliated organization the Tianjin Institute of Industrial Biotechnology (TIB).
The CAS recognized Distinguished Professor Lee for his significant contributions to biotechnology. He has made significant pioneering academic achievements in the area of systems metabolic engineering, which produces useful chemicals from microorganisms. Not only did he develop the first and best source technology in that field, but also came out with processes for the production of biofuel and environmentally-friendly chemicals.”
As a global leader in systems metabolic engineering, Distinguished Professor Lee has also been appointed as an honorary professor at Jiangnan University in Wuxi, China.
Distinguished Professor Lee was listed in the ‘Top 20 Translational Researchers of 2014’ selected by the renowned international journal Nature Biotechnology. Moreover, he was the first Asian recipient of the James E. Bailey Award in 2016 and Marvin J. Johnson Award in 2012, which are given to scholars in the field of biotechnology.
He is also one of 13 global scientists who are foreign members of the renowned academic societies the National Academy of Engineering and the National Academy of Sciences in the US. Furthermore, he received the ‘2017 Korea Best Scientist Award’ from the president of Korea in July. Finally, his founding field, systems metabolic engineering, was chosen as one of the ‘Top 10 Emerging Technologies of 2016’ by the World Economic Forum.
The Chinese Academy of Sciences, established in November 1949, is an academic organization that carries out research on basic sciences and natural sciences in China. It defined its science and technology system to include the fields of basic sciences, natural sciences, and high technology. While having a base in Beijing, its branch academies are located in 12 main cities along with 117 affiliates and 100 national key labs.
2017.10.26 View 12044 -
Development of a Highly-Accurate Computational Model of Human Metabolism
A research team from KAIST developed a computational framework that enables the reconstruction of a comprehensive computational model of human metabolism, which allows for an accurate prediction of personal metabolic features (or phenotypes).
Understanding personal metabolic phenotypes allows us to design effective therapeutic strategies for various chronic and infectious diseases. A human computational model called the genome-scale metabolic model (GEM) contains information on thousands of metabolic genes and their corresponding reactions and metabolites, and has played an important role in predicting metabolic phenotypes. Although several versions of human GEMs have been released, they had room for further development, especially as to incorporating biological information coming from a human genetics mechanism called “alternative splicing.” Alternative splicing is a genetic mechanism that allows a gene to give rise to multiple reactions, and is strongly associated with pathology.
To tackle this problem, Jae Yong Ryu (a Ph.D. student), Dr. Hyun Uk Kim (Research Fellow), and Distinguished Professor Sang Yup Lee, all from the Department of Chemical and Biomolecular Engineering at KAIST, developed a computational framework that systematically generates metabolic reactions, and adds them to the human GEM. The resulting human GEM was demonstrated to accurately predict metabolic phenotypes under varied environmental conditions. The research results were published online in Proceedings of the National Academy of Sciences (PNAS) on October 24, 2017, under the title “Framework and resource for more than 11,000 gene-transcript-protein-reaction associations in human metabolism.”
The research team first updated the biological contents of a previous version of the human GEM. The updated biological contents include metabolic genes and their corresponding metabolites and reactions. In particular, metabolic reactions catalyzed by already-known protein isoforms were additionally incorporated into the human GEM; protein isoforms are multiple variants of proteins generated from individual genes through the alternative splicing process. Each protein isoform is often responsible for the operation of a metabolic reaction. Although multiple protein isoforms generated from one gene can play different functions by having different sets of protein domains and/or subcellular localizations, such information was not properly considered in previous versions of human GEMs.
Upon the initial update of the human GEM, named Recon 2M.1, the research team subsequently implemented a computational framework that systematically generates information on Gene-Transcript-Protein-Reaction Associations (GeTPRA) in order to identify protein isoforms that were previously not identified. This framework was developed in this study. As a result of the implementation of the framework for GeTPRA, more than 11,000 GeTPRA were automatically predicted, and thoroughly validated. Additional metabolic reactions were then added to Recon 2M.1 based on the predicted GeTPRA for the previously uncharacterized protein isoforms; Recon 2M.1 was renamed Recon 2M.2 from this upgrade.
Finally, Recon 2M.2 was integrated with 446 sets of personal biological data (RNA-Seq data) in order to build patient-specific cancer models. These patient-specific cancer models were used to predict cancer metabolism activities and anticancer targets.
The development of a new version of human GEMs along with the computational framework for GeTPRA is expected to boost studies in fundamental human genetics and medicine. Model files of the human GEMs Recon 2M.1 and 2M.2, a full list of the GeTPRA and the source code for the computational framework to predict the GeTPRA are all available as part of the publication of this study.
Distinguished Professor Lee said, “The predicted GeTPRA from the computational framework is expected to serve as a guideline for future experiments on human genetics and biochemistry, whereas the resulting Recon 2M.2 can be used to predict drug targets for various human diseases.”
This work was supported by the Technology Development Program to Solve Climate Changes on Systems Metabolic Engineering for Biorefineries (NRF-2012M1A2A2026556 and NRF-2012M1A2A2026557) from the Ministry of Science and ICT through the National Research Foundation (NRF) of Korea.
(Figure 1:A scheme of Recon 2M.1 development and its use in reconstructing personal genome-scale metabolic models (GEMs). (A) A concept of alternative splicing of human genes and its use in Gene-Transcript-Protein-Reaction Associations (GeTPRA) of Recon 2M.1. (B) A procedure of systematic refinement of the Recon 2Q. Recon 2Q is one of the previously released human GEMs. Biochemically inconsistent reactions include unbalanced, artificial, blocked, and/or redundant reactions. Iterative manual curation was conducted while validating the Recon 2M.1. (C) Reconstruction of cancer patient-specific GEMs using Recon 2M.1 for further simulation studies. In this study, personal biological data (RNA-Seq data) were obtained from The Cancer Genome Atlas (TCGA; https://cancergenome.nih.gov/ ) across the ten cancer types.
(Figure 2: Computational framework for the systematic generation of Gene-Transcript-Protein-Reaction Associations (GeTPRA; red box in the flowchart). Peptide sequences of metabolic genes defined in Recon 2M.1 were retrieved from a database called Ensembl. EC numbers and subcellular localizations of all the protein isoforms of metabolic genes in Recon 2M.1 were predicted using software programs EFICAz2.5 and Wolf PSort, respectively. Information on the newly predicted GeTPRA was systematically incorporated into the Recon 2M.1, thereby resulting in Recon 2M.2.)
2017.10.25 View 10329 -
Ultra-Fast and Ultra-Sensitive Hydrogen Sensor
(From left: Professor Kim, Ph.D. candidate Koo, and Professor Penner)
A KAIST team made an ultra-fast hydrogen sensor that can detect hydrogen gas levels under 1% in less than seven seconds. The sensor also can detect hundreds of parts per million levels of hydrogen gas within 60 seconds at room temperature.
A research group under Professor Il-Doo Kim in the Department of Materials Science and Engineering at KAIST, in collaboration with Professor Reginald M. Penner of the University of California-Irvine, has developed an ultra-fast hydrogen gas detection system based on a palladium (Pd) nanowire array coated with a metal-organic framework (MOF).
Hydrogen has been regarded as an eco-friendly next-generation energy source. However, it is a flammable gas that can explode even with a small spark. For safety, the lower explosion limit for hydrogen gas is 4 vol% so sensors should be able to detect the colorless and odorless hydrogen molecule quickly. The importance of sensors capable of rapidly detecting colorless and odorless hydrogen gas has been emphasized in recent guidelines issued by the U.S. Department of Energy. According to the guidelines, hydrogen sensors should detect 1 vol% of hydrogen in air in less than 60 seconds for adequate response and recovery times.
To overcome the limitations of Pd-based hydrogen sensors, the research team introduced a MOF layer on top of a Pd nanowire array. Lithographically patterned Pd nanowires were simply overcoated with a Zn-based zeolite imidazole framework (ZIF-8) layer composed of Zn ions and organic ligands. ZIF-8 film is easily coated on Pd nanowires by simple dipping (for 2–6 hours) in a methanol solution including Zn (NO3)2·6H2O and 2-methylimidazole.
(This cover image depicts lithographically-patterned Pd nanowires overcoated with a Zn-based zeolite imidazole framework (ZIF-8) layer.)
As synthesized ZIF-8 is a highly porous material composed of a number of micro-pores of 0.34 nm and 1.16 nm, hydrogen gas with a kinetic diameter of 0.289 nm can easily penetrate inside the ZIF-8 membrane, while large molecules (> 0.34 nm) are effectively screened by the MOF filter. Thus, the ZIF-8 filter on the Pd nanowires allows the predominant penetration of hydrogen molecules, leading to the acceleration of Pd-based H2 sensors with a 20-fold faster recovery and response speed compared to pristine Pd nanowires at room temperature.
Professor Kim expects that the ultra-fast hydrogen sensor can be useful for the prevention of explosion accidents caused by the leakage of hydrogen gas. In addition, he expects that other harmful gases in the air can be accurately detected through effective nano-filtration by using of a variety of MOF layers.
This study was carried out by Ph.D. candidate Won-Tae Koo (first author), Professor Kim (co-corresponding author), and Professor Penner (co-corresponding author). The study has been published in the online edition of ACS Nano, as the cover-featured image for the September issue.
Figure 1. Representative image for this paper published in ACS Nano, August, 18.
Figure 2. Images of Pd nanowire array-based hydrogen sensors, scanning electron microscopy image of a Pd nanowire covered by a metal-organic framework layer, and the hydrogen sensing properties of the sensors.
Figure 3. Schematic illustration of a metal-organic framework (MOF). The MOF, consisting of metal ions and organic ligands, is a highly porous material with an ultrahigh surface area. The various structures of MOFs can be synthesized depending on the kinds of metal ions and organic ligands.
2017.09.28 View 11163 -
KAIST-WEF Roundtable on Inclusive Growth and Job Creation
The World Economic Forum (WEF) will join KAIST in an effort to address sweeping global problems in the wake of the Fourth Industrial Revolution. The two will co-host a roundtable on ‘Shaping Korea’s Priorities for Inclusive Growth and Job Creation in the Fourth Industrial Revolution’ on October 13 at Lotte Hotel in Seoul.
The roundtable will bring together leaders from government, industry, universities, and non-profit civic organizations to have an in-depth discussion on a thought-provoking agenda of inclusive growth and job creation which scientific and technological changes will bring about. The event will provide a platform to explore practical collaboration and innovative strategies for better job creation and innovation ecosystems.
The two will also sign an MOU for collaboration between the Fourth Industrial Revolution Information Center (FIRIC) of KAIST and the WEF Center for the Fourth Industrial Revolution (C4IR).
President Sung-Chul Shin of KAIST and the Head of the WEF Center for the Fourth Industrial Revolution, Murat Sonmez, will lead the panel discussion titled ‘Inclusive Growth and the Fourth Industrial Revolution’ which will be attended by leaders from government, industry, and non-profit civic organizations.
At the breakout sessions, the topics will be “Future Jobs” and the “Creation of Innovation Ecosystems”. Additionally, a discussion on the “SME 4.0 Initiative”, which is a program pushed forward by KAIST in collaboration with local governments, will talk about job creation through innovation in small and medium-sized enterprises (SMEs). The WEF will introduce their two-year activities and research on the Fourth Industrial Revolution, which have great potential and a high possibility of successfully undergoing the revolution, to Korea.
Since WEF Executive Chairman Klaus Schwab brought up the topic of the Fourth Industrial Revolution, the WEF has been leading agenda topics and discussions on high-profile matters, including ‘technology-driven but human-centered inclusive growth’ in predicting the future of jobs.
The WEF is a nonprofit organization committed to addressing the world’s weightiest problems. It is best known for its annual meetings in Davos, Switzerland, which attracts leaders from around the world. KAIST has been participating in this summit since 2009. President Shin will also attend the upcoming Davos summit next January. Distinguished Professor Sang Yup Lee who heads the KAIST Institute and the FIRIC is the co-chair of the Global Council on Biotechnology and a member of the Global Future Council on the Fourth Industrial Revolution at the WEF.
Moreover, President Shin and Mr. Sonmez will explain the background of the roundtable and share the results of the sessions at a joint news conference.
2017.09.28 View 10464 -
Unlocking the Keys to Parkinson's Disease
A KAIST research team has identified a new mechanism that causes the hallmark symptoms of Parkinson’s disease, namely tremors, rigidity, and loss of voluntary movement.
The discovery, made in collaboration with Nanyang Technological University in Singapore, presents a new perspective to three decades of conventional wisdom in Parkinson’s disease research. It also opens up new avenues that can help alleviate the motor problems suffered by patients of the disease, which reportedly number more than 10 million worldwide. The research was published in Neuron on August 30.
The research team was led by Professor Daesoo Kim from the Department of Biological Sciences at KAIST and Professor George Augustine from the Lee Kong Chian School of Medicine at NTU. Dr. Jeongjin Kim, a former postdoctoral fellow at KAIST who now works at the Korea Institute of Science and Technology (KIST), is the lead author.
It is known that Parkinson’s disease is caused by a lack of dopamine, a chemical in the brain that transmits neural signals. However, it remains unknown how the disease causes the motor
Smooth, voluntary movements, such as reaching for a cup of coffee, are controlled by the basal ganglia, which issue instructions via neurons (nerve cells that process and transmit information in the brain) in the thalamus to the cortex. These instructions come in two types: one that triggers a response (excitatory signals) and the other that suppresses a response (inhibitory signals). Proper balance between the two controls movement.
A low level of dopamine causes the basal ganglia to severely inhibit target neurons in the thalamus, called an inhibition. Scientists have long assumed that this stronger inhibition causes the motor problems of Parkinson’s disease patients.
To test this assumption, the research team used optogenetic technology in an animal model to study the effects of this increased inhibition of the thalamus and ultimately movement. Optogenetics is the use of light to control the activity of specific types of neurons within the brain.
They found that when signals from the basal ganglia are more strongly activated by light, the target neurons in the thalamus paradoxically became hyperactive. Called rebound excitation, this hyperactivity produced abnormal muscular stiffness and tremor. Such motor problems are very similar to the symptoms of Parkinson’s disease patients. When this hyperactivity of thalamic neurons is suppressed by light, mice show normal movments without Parkinson’s disease symptoms. Reducing the levels of activity back to normal caused the motor symptoms to stop, proving that the hyperactivity caused the motor problems experienced by Parkinson’s disease patients.
Professor Kim at KAIST said, “This study overturns three decades of consensus on the provenance of Parkinsonian symptoms.” The lead author, Dr Jeongjin Kim said, “The therapeutic implications of this study for the treatment of Parkinsonian symptoms are profound. It may soon become possible to remedy movement disorders without using L-DOPA, a pre-cursor to dopamine.”
Professor Augustine at NTU added, “Our findings are a breakthrough, both for understanding how the brain normally controls the movement of our body and how this control goes awry during Parkinson’s disease and related dopamine-deficiency disorders.”
The study took five years to complete, and includes researchers from the Department of Bio & Brain Engineering at KAIST.
The research team will move forward by investigating how hyperactivity in neurons in the thalamus leads to abnormal movement, as well as developing therapeutic strategies for the disease by targeting this neural mechanism.
Figure abstract: Inhibitory inputs from the basal ganglia inhibit thalamic neurons (upper). In low-dopamine states, like PD, rebound firing follows inhibition and causes movement disorders (middle). The inhibition of rebound firing alleviates PD-like symptoms in a mouse model of PD.
2017.09.22 View 10810