[대학원 생명과학과 세미나 안내]
연사 : 김진현 박사(KIST 뇌과학연구소)
연제 : mGRASP for mapping mammalian synaptic circuit at multiple scales
일시 : 2016년 9월 23일 (금) 오후 4시
장소 : 하나과학관 A동 109호
초청교수 : 윤봉준 교수
Abstract
Mapping mammalian synaptic connectivity has longbeen an important goal of neuroscientists since it is considered crucial forexplaining human perception and behavior. Our new genetically controlled methodto resolve synapses at the level of LM, termed mammalian GFP reconstitutionacross synaptic partners (mGRASP), is synapse-specific labeling with twocomplementary GFP components. mGRASP isbased on two non-fluorescent split-GFP fragments (called spGFP1-10 and spGFP11)tethered to synaptic membranes in each of two neuronal populations. When twoneurons, each expressing one of the fragments, are tightly opposed across asynaptic cleft, fluorescent GFP is reconstituted. mGRASP can relatively quicklyreveal the precise locations and numbers of synapses along postsynapticdendrites, sites responsible for determining many important characteristics ofsignal processing. Thus, mGRASP technology is suitable for mapping large-scale connectivitypatterns at multiple scales: micro-scale forsynapse-by-synapse or neuron-by-neuron analysis; and meso-scale for revealinglocal circuits. Weperformed a comprehensive fine-scale circuit mapping of hippocampal regionsusing the mGRASP. This mapping revealedspatially non-uniform and clustered synaptic connectivity patterns.Furthermore, synaptic clustering was enhanced between groups of neurons thatshared a similar developmental/migration time window, suggesting a mechanismfor establishing the spatial structure of synaptic connectivity. Suchconnectivity patterns are thought to effectively engage active dendriticprocessing and storage mechanisms, thereby potentially enhancing neuronalfeature selectivity. Based on these prime connectivity characteristics, ourstudy recently focuses on understanding synaptic connectivity profilesassociated with neurological disorders using mGRASP.