Functional Differentiation of Cholecystokinin-Containing Interneurons Destined for the Cerebral Cortex



Calvigioni, Daniela, Mate, Zoltan, Fuzik, Janos, Girach, Fatima, Zhang, Ming-Dong, Varro, Andrea, Beiersdorf, Johannes, Schwindling, Christian, Yanagawa, Yuchio, Dockray, Graham J
et al (show 5 more authors) (2017) Functional Differentiation of Cholecystokinin-Containing Interneurons Destined for the Cerebral Cortex. CEREBRAL CORTEX, 27 (4). pp. 2453-2468.

Access the full-text of this item by clicking on the Open Access link.

Abstract

Although extensively studied postnatally, the functional differentiation of cholecystokinin (CCK)-containing interneurons en route towards the cerebral cortex during fetal development is incompletely understood. Here, we used CCKBAC/DsRed mice encoding a CCK promoter-driven red fluorescent protein to analyze the temporal dynamics of DsRed expression, neuronal identity, and positioning through high-resolution developmental neuroanatomy. Additionally, we developed a dual reporter mouse line (CCKBAC/DsRed::GAD67gfp/+) to differentiate CCK-containing interneurons from DsRed+ principal cells during prenatal development. We show that DsRed is upregulated in interneurons once they exit their proliferative niche in the ganglionic eminence and remains stably expressed throughout their long-distance migration towards the cerebrum, particularly in the hippocampus. DsRed+ interneurons, including a cohort coexpressing calretinin, accumulated at the palliosubpallial boundary by embryonic day 12.5. Pioneer DsRed+ interneurons already reached deep hippocampal layers by embryonic day 14.5 and were morphologically differentiated by birth. Furthermore, we probed migrating interneurons entering and traversing the cortical plate, as well as stationary cells in the hippocampus by patch-clamp electrophysiology to show the first signs of Na+ and K+ channel activity by embryonic day 12.5 and reliable adult-like excitability by embryonic day 18.5. Cumulatively, this study defines key positional, molecular, and biophysical properties of CCK+ interneurons in the prenatal brain.

Item Type: Article
Uncontrolled Keywords: cortical plate, light sheet microscopy, migration, specification, synaptogenesis, transgene reporter
Depositing User: Symplectic Admin
Date Deposited: 13 Jun 2018 08:28
Last Modified: 19 Jan 2023 01:32
DOI: 10.1093/cercor/bhw094
Open Access URL: https://doi.org/10.1093/cercor/bhw094
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3022507