In the adult brain, synapses undergo constant formation and elimination. However, the exact function and DBS
이준혁. 별아교세포의 성체 시냅스 포식에 의한 구조적 가소성 연구. 생명과학과. 2022년. 134+vi 쪽. 지도교수: 정원석. (영문 논문) Joon-Hyuk Lee. Mechanisms of Structural Plasticity of adult synapses by Astrocytic Phagocytosis. 2022. 134+vi pages. Advisor: Won-Suk Chung. (Text in English)
ii
regulatory process of synapse elimination in the adult brain are largely unknown. Here, we reveal a significant role of astrocytic phagocytosis in the diverse region of adult brain. By utilizing mCherry-eGFP phagocytosis reporters, we find that synapses are eliminated by astrocytic phagocytosis in the adult hippocampal CA1, primary visual cortex and olfactory bulb. Surprisingly, our data show that astrocyte-mediated synapse elimination is critical for maintaining synaptic homeostasis as well as synapse remodeling in response to sensory alteration and neurogenesis. Furthermore, knocking-out the phagocytic receptor Megf10 in adult astrocytes reduces their ability to eliminate excitatory synapses, and as a result, induces the deficits in the synapse remodeling. Taken together, our data provide strong evidence that astrocytes eliminate the unwanted excitatory synaptic connections in the adult brain through MEGF10-dependent phagocytosis, and that this astrocytic function is critical for structural synaptic plasticity.