Molecules and Cells

  • 제45권2호
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  • Pages.84-92
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  • 2022
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  • 1016-8478(pISSN)
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  • 0219-1032(eISSN)
한국분자세포생물학회 (Korean Society for Molecular and Cellular Biology)
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Finding Needles in a Haystack with Light: Resolving the Microcircuitry of the Brain with Fluorescence Microscopy

  • Rah, Jong-Cheol (Laboratory of Neurophysiology, Korea Brain Research Institute) ;
  • Choi, Joon Ho (Laboratory of Neurophysiology, Korea Brain Research Institute)
  • 투고 : 2021.11.14
  • 심사 : 2021.12.20
  • 발행 : 2022.02.28
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⟨ 이전 논문 다음 논문 ⟩

초록

To understand the microcircuitry of the brain, the anatomical and functional connectivity among neurons must be resolved. One of the technical hurdles to achieving this goal is that the anatomical connections, or synapses, are often smaller than the diffraction limit of light and thus are difficult to resolve by conventional microscopy, while the microcircuitry of the brain is on the scale of 1 mm or larger. To date, the gold standard method for microcircuit reconstruction has been electron microscopy (EM). However, despite its rapid development, EM has clear shortcomings as a method for microcircuit reconstruction. The greatest weakness of this method is arguably its incompatibility with functional and molecular analysis. Fluorescence microscopy, on the other hand, is readily compatible with numerous physiological and molecular analyses. We believe that recent advances in various fluorescence microscopy techniques offer a new possibility for reliable synapse detection in large volumes of neural circuits. In this minireview, we summarize recent advances in fluorescence-based microcircuit reconstruction. In the same vein as these studies, we introduce our recent efforts to analyze the long-range connectivity among brain areas and the subcellular distribution of synapses of interest in relatively large volumes of cortical tissue with array tomography and superresolution microscopy.

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과제정보

This work was supported by grants from the KBRI Research Program (21-BR-01-01, 21-BR-01-04, and 21-BR-03-01), from the DGIST R&D Program (21-IJRP-01), and from the Brain Research Program through the National Research Foundation of Korea (NRF) of the Ministry of Science and ICT (NRF-2017M3C7A1048086 and No. 2017M3A9G8084463).

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