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bioRxiv · 10.1101/627505

Transcriptomic evidence that von Economo neurons are regionally specialized extratelencephalic-projecting excitatory neurons

Abstract

von Economo neurons (VENs) are bipolar, spindle-shaped neurons restricted to layer 5 of human frontoinsula and anterior cingulate cortex that appear to be selectively vulnerable to neuropsychiatric and neurodegenerative diseases, although little is known about other VEN cellular phenotypes. Single nucleus RNA-sequencing of frontoinsula layer 5 identified a transcriptomically-defined cell cluster that contained VENs, but also fork cells and a subset of pyramidal neurons. Cross-species alignment of this cell cluster with a well-annotated mouse classification shows strong homology to extratelencephalic (ET) excitatory neurons that project to subcerebral targets. This cluster also shows strong homology to a putative ET cluster in human temporal cortex, but with a strikingly specific regional signature. Together these results predict VENs are a regionally distinctive type of ET neuron, and we additionally describe the first patch clamp recordings of VENs from neurosurgically-resected tissue that show distinctive intrinsic membrane properties relative to neighboring pyramidal neurons.

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BibTeXRIS

Hodge, R. D., Miller, J. A., Novotny, M. D., Kalmbach, B. D., Ting, J. T., Bakken, T. E., Aevermann, B. D., Barkan, E. R., Berkowitz-Cerasano, M. L., Cobbs, C., Diez-Fuertes, F., Ding, S.-L., McCorrison, J., Schork, N. J., Shehata, S. I., Smith, K. A., Sunkin, S. M., Tran, D. N., Venepally, P., Yanny, A. M., Steemers, F. J., Phillips, J. W., Bernard, A., Koch, C., Lasken, R. S., Scheuermann, R. H., Lein, E. S.. 2019-05-07. Transcriptomic evidence that von Economo neurons are regionally specialized extratelencephalic-projecting excitatory neurons. https://doi.org/10.1101/627505

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