東京大学 · 신경과학
하루카이 교수의 연구실은 시냅스 구조의 동적 변화와 뇌의 학습·기억 메커니즘을 중심으로 연구를 진행합니다. 특히 도파민과 글루타메이트의 시계열적 활성화가 시냅스 강화에 미치는 영향, 뇌유도신경영화소인자(BDNF)와 단백질 합성의 역할, 그리고 시냅스 스파이크의 구조적 변화가 기억 형성에 어떻게 기여하는지에 중점을 두고 있습니다. 연구는 주로 두광형 영상, 전기생리학, 광자극 기반 시냅스 조작 기법을 통해 실시되며, 뇌의 구조적 가소성과 학습의 세포막대기반 메커니즘을 규명하는 데 목적이 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
Animal behaviors are reinforced by subsequent rewards following within a narrow time window. Such reward signals are primarily coded by dopamine, which modulates the synaptic connections of medium spiny neurons in the striatum. The mechanisms of the narrow timing detection, however, remain unknown. Here, we optically stimulated dopaminergic and glutamatergic inputs separately and found that dopamine promoted spine enlargement only during a narrow time window (0.3 to 2 seconds) after the glutamat
Long-term potentiation (LTP) at glutamatergic synapses is considered to underlie learning and memory and is associated with the enlargement of dendritic spines. Because the consolidation of memory and LTP require protein synthesis, it is important to clarify how protein synthesis affects spine enlargement. In rat brain slices, the repetitive pairing of postsynaptic spikes and two-photon uncaging of glutamate at single spines (a spike-timing protocol) produced both immediate and gradual phases of
Long-term potentiation of synapse strength requires enlargement of dendritic spines on cerebral pyramidal neurons. Long-term depression is linked to spine shrinkage. Indeed, spines are dynamic structures: they form, change their shapes and volumes, or can disappear in the space of hours. Do all such changes result from synaptic activity, or do some changes result from intrinsic processes? How do enlargement and shrinkage of spines relate to elimination and generation of spines, and how do these
1. Pharmacological and kinetic properties of high-voltage-activated (HVA) Ca2+ channel currents were studied using the whole-cell and perforated patch-clamp methods in a mouse neuroblastoma and rat glioma hybrid cell line, NG108-15, differentiated by dibutyryl cyclic AMP or by prostaglandin E1 and theophylline. 2. The HVA currents were separated into two components by use of two organic Ca2+ channel antagonists, omega-conotoxin GVIA (omega CgTX) and a dihydropyridine (DHP) compound, nifedipine.
The dynamics of exocytosis are diverse and have been optimized for the functions of synapses and a wide variety of cell types. For example, the kinetics of exocytosis varies by more than five orders of magnitude between ultrafast exocytosis in synaptic vesicles and slow exocytosis in large dense-core vesicles. However, in all cases, exocytosis is mediated by the same fundamental mechanism, i.e., the assembly of soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein
Structural plasticity of dendritic spines underlies learning, memory and cognition in the cerebral cortex. We here summarize fifteen rules of spine structural plasticity, or 'spine learning rules.' Together, they suggest how the spontaneous generation, selection and strengthening (SGSS) of spines represents the physical basis for learning and memory. This SGSS mechanism is consistent with Hebb's learning rule but suggests new relations between synaptic plasticity and memory. We describe the cell
