Astrocytic connection to engram neurons increased after learning

Kim, J.; Sung, Y.; Park, H.; Choi, D. I.; Kim, J.-i.; Lee, H.; Jung, M. K.; Noh, S.; Ye, S.; Lee, J.; Islam, M. A.; Chun, H.; Mun, J. Y.; Kaang, B.-K.

doi:10.1101/2023.01.25.525617

bioRxiv · 10.1101/2023.01.25.525617

Astrocytic connection to engram neurons increased after learning

Kim, J.·Sung, Y.·Park, H.·Choi, D. I.·Kim, J.-i.·Lee, H.·Jung, M. K.·Noh, S.·Ye, S.·Lee, J.·Islam, M. A.·Chun, H.·Mun, J. Y.·Kaang, B.-K.

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Abstract

Astrocytes directly participate in learning and memory. However, the structural association between astrocytes and memory-encoding engram neurons after learning remains to be elucidated. We developed astrocyte-enhanced green fluorescent protein reconstitution across synaptic partners (eGRASP) to examine tripartite synapses between astrocytes and engram neurons. Using astrocyte-eGRASP, we found that astrocytes had increased connections to engram neurons after learning. Dendritic spines with astrocytic contacts showed enhanced morphology. Live-cell imaging of astrocyte-eGRASP revealed that astrocytic connections are stabilized by neuronal activity. These results indicate that astrocytes distinguish contact between engram neurons and generate engram-specific contact patterns during learning.

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Kim, J., Sung, Y., Park, H., Choi, D. I., Kim, J.-i., Lee, H., Jung, M. K., Noh, S., Ye, S., Lee, J., Islam, M. A., Chun, H., Mun, J. Y., Kaang, B.-K.. 2023-01-26. Astrocytic connection to engram neurons increased after learning. https://doi.org/10.1101/2023.01.25.525617

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