Zoom link: https://tuni.zoom.us/j/61967963989
Laura Keto, Tiina Manninen
The cerebellar circuitry has been modeled widely, with realistic and accurate models now existing for most of the cerebellar neurons [1]. The glial cell population of the cerebellum, however, has been largely neglected by computational modelers. No realistic whole-cell models have been previously implemented for any of the cerebellar glial cell types; oligodendrocytes, microglia, or astroglia. In this work, we were interested in reconstructing a detailed morphology for the best-known cerebellar astroglial cell type, Bergman glia. Bergmann glia are radial astrocytes of the cerebellar cortex, with somata located at the Purkinje cell layer, 3-6 long processes extending through the molecular layer, and endfeet. The processes give rise to smaller appendages characterized by microdomains that enwrap neuronal synapses [2]. The reciprocal communication between Bergmann glia and the neighboring neurons is vital for development and plasticity of the cerebellum [3].
Currently no reconstructions of cerebellar glial cells are available in public databases. The reconstruction of Bergmann glia required both an astroglial stem tree as well as a more detailed morphology for reconstructing the astroglial nanoscopic architecture. The stem tree was built with the NEURON CellBuilder tool [4] with values found from literature [2,5]. For the nanoscopic architecture, a 3D reconstruction of a Bergmann glial appendage was recreated based on a video file [2] with AgiSoft Metashape and Blender. As the exact reconstruction of the nanoscopic architecture would be computationally unfeasible, a novel computational tool ASTRO [6] was used to define statistical properties from the reconstructed appendage. The final morphology was assembled with ASTRO and verified functionally by simulating microscopic calcium dynamics with the tool.
Acknowledgements
We are very grateful to Prof. Helmut Kettenmann for providing us the video file of Bergmann glia appendage. The work was supported by Academy of Finland (Nos. 326494, 326495).
References
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