KAIST 생명과학과동창회
  • News & Events
  • News


Astrocytes eat connections to maintain plasticity in adult brains


by The Korea Advanced Institute of Science and Technology (KAIST) 



    Astrocytes eat connections to maintain plasticity in adult brains

A 3-D image showing our synapse phagocytosis reporter in mouse hippocampus


Developing brains constantly sprout new neuronal connections called synapses as they learn and remember. Important connectionsthe ones that are repeatedly introduced, such as how to avoid dangerare nurtured and reinforced, while connections deemed unnecessary are pruned away. Adult brains undergo similar pruning, but it was unclear how or why synapses in the adult brain get eliminated.                      


Now, a team of KAIST researchers has found the mechanism underlying plasticity and, potentially, neurological disorders in adult brains. They published their findings on December 23 in Nature.


"Our findings have profound implications for our understanding of how neural circuits change during learning and memory, as well as in diseases," said paper author Won-Suk Chung, an assistant professor in the Department of Biological Sciences at KAIST. "Changes in synapse number have strong association with the prevalence of various neurological disorders, such as autism spectrum disorder, schizophrenia, frontotemporal dementia, and several forms of seizures."


Gray matter in the brain contains microglia and astrocytes, two complementary cells that, among other things, support neurons and synapses. Microglial are a frontline immunity defense, responsible for eating pathogens and dead cells, and astrocytes are star-shaped cells that help structure the brain and maintain homeostasis by helping to control signaling between neurons. According to Professor Chung, it is generally thought that microglial eat synapses as part of its clean-up effort in a process known as phagocytosis.


"Using novel tools, we show that, for the first time, it is astrocytes and not microglia that constantly eliminate excessive and unnecessary adult excitatory synaptic connections in response to neuronal activity," Professor Chung said. "Our paper challenges the general consensus in this field that microglia are the primary synapse phagocytes that control synapse numbers in the brain."


Professor Chung and his team developed a molecular sensor to detect synapse elimination by glial cells and quantified how often and by which type of cell synapses were eliminated. They also deployed it in a mouse model without MEGF10, the gene that allows astrocytes to eliminate synapses. Adult animals with this defective astrocytic phagocytosis had unusually increased excitatory synapse numbers in the hippocampus. Through a collaboration with Dr. Hyungju Park at KBRI, they showed that these increased excitatory synapses are functionally impaired, which cause defective learning and memory formation in MEGF10 deleted animals.


"Through this process, we show that, at least in the adult hippocampal CA1 region, astrocytes are the major player in eliminating synapses, and this astrocytic function is essential for controlling synapse number and plasticity," Chung said.


Professor Chung noted that researchers are only beginning to understand how synapse elimination affects maturation and homeostasis in the brain. In his group's preliminary data in other brain regions, it appears that each region has different rates of synaptic elimination by astrocytes. They suspect a variety of internal and external factors are influencing how astrocytes modulate each regional circuit, and plan to elucidate these variables.


"Our long-term goal is understanding how astrocyte-mediated synapse turnover affects the initiation and progression of various neurological disorders," Professor Chung said. "It is intriguing to postulate that modulating astrocytic phagocytosis to restore synaptic connectivity may be a novel strategy in treating various brain disorders."








List of Articles
번호 제목 글쓴이 날짜 조회 수
84 전상용 교수, Theranostics 저널 최다 피인용 논문상 수상 / Professor Sangyong Jon receives The Most Cited Paper Award by the “Theranostics” Journal 과사무실 2015.04.22 11444
83 전상용 교수, 몸 속 물질 이용한 염증 치료제 개발 / Prof. Sang-Yong Jon developed anti-inflammatory drug using biological materials 생명과학과 2016.06.15 15859
82 전상용 교수, 암 치료를 위한 새로운 펩타이드-항체 복합체(하이브리드) 기술 개발 file 생명과학과 2019.02.21 4827
81 전상용 교수, 차세대 면역항암제 플랫폼 개발 위한 공동연구협약 체결 / Professor Sangyong Jon, make a research-cooperation contract for developing next-genreation anti-cancer drug platform 관리자 2016.01.08 14148
80 전상용 교수님_ 면역항암제 효율 높인 나노입자 백신 개발 file 생명과학과 2020.06.17 2178
79 전상용 교수님_Researchers review future directions of nanomedicine development 생명과학과 2020.12.28 335
78 전상용,이대엽 임성갑 교수, 암 줄기세포 제작 원천기술 개발 file 생명과학과 2018.11.30 5049
77 전상용교수님_항암제 표적 단백질을 약물 전달체로 쓴다?​ file 생명과학과 2020.08.26 1348
76 정원석 교수_ 삼성전자, ‘세계 알츠하이머의 날’ 맞아 연구원 노력 담은 영상 공개 생명과학과 2020.09.21 1560
» 정원석 교수님_Astrocytes eat connections to maintain plasticity in adult brains 생명과학과 2020.12.28 604
74 정원석 교수님_국내 연구진, 우리 뇌가 계속 일할 수 있는 이유 밝혀 생명과학과 2021.02.26 31
73 정유진 석사과정 학생, 조병관 교수 Nature Communications 논문 게재(2016.06) / Yujin Jeong, a Master's degree student and Prof. Byung-Kwan Cho published a paper in Nature Communications (2016.06) 생명과학과 2016.06.07 11725
72 정인경 교수, 인체 조직읜 3차원 게놈지도 해독 file 생명과학과 2019.09.25 3601
71 정인경 교수님_KAIST, 전 세계 최대 규모의 3차원 암 게놈 지도 구축 생명과학과 2020.12.29 557
70 정종경 교수 이달의 과학기술자상 12월 수상자로 선정 과사무실 2006.12.11 11492
69 정현정 교수, 한국 로레알-유네스코 여성과학자상 펠로우십 수상 file 생명과학과 2019.07.04 4554
68 정현정 교수님_도파민의 성질로 박테리아 생장의 실시간 탐지 기술 개발​ 생명과학과 2020.12.09 581
67 정현정교수_ 커피링 효과로 감염병 신속진단 기술 개발 생명과학과 2020.09.17 1303
66 정형록 박사과정 학생, 최광욱 교수 Development Cell 게재(2016.02) / Hyung-Lok Chung, a Ph.D candidate and Prof. Kwang-Wook Choi published a paper in Dev. Cell (2016.02) 생명과학과 2016.03.11 11129
65 제1회 젊은 파스퇴르상 카이스트 석권! 과사무실 2010.03.03 10884
Board Pagination Prev 1 ... 8 9 10 11 12 13 14 15 16 17 Next
/ 17