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Hippocampal CA1 Somatostatin Interneurons Originate in the Embryonic MGE/POA.

ABSTRACT: Oriens lacunosum-moleculare (O-LM) interneurons constitute 40% of hippocampal interneurons expressing Somatostatin (SST). Recent evidence has indicated a dual origin for these cells in the medial and caudal ganglionic eminences (MGE and CGE), with expression of Htr3a as a distinguishing factor. This is strikingly different from cortical SST interneurons that have a single origin within the MGE/preoptic area (POA). We reassessed the origin of hippocampal SST interneurons using a range of genetic lineage-tracing mice combined with single-cell transcriptomic analysis. We find a common origin for all hippocampal SST interneurons in NKX2-1-expressing progenitors of the telencephalic neuroepithelium and an MGE/POA-like transcriptomic signature for all SST clusters. This suggests that functional heterogeneity within the SST CA1 population cannot be attributed to a differential MGE/CGE genetic origin.

SUBMITTER: Asgarian Z

PROVIDER: S-EPMC6895756 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Hippocampal CA1 Somatostatin Interneurons Originate in the Embryonic MGE/POA.

Asgarian Zeinab Z Magno Lorenza L Ktena Niki N Harris Kenneth D KD Kessaris Nicoletta N

Stem cell reports 20191017 5

Oriens lacunosum-moleculare (O-LM) interneurons constitute 40% of hippocampal interneurons expressing Somatostatin (SST). Recent evidence has indicated a dual origin for these cells in the medial and caudal ganglionic eminences (MGE and CGE), with expression of Htr3a as a distinguishing factor. This is strikingly different from cortical SST interneurons that have a single origin within the MGE/preoptic area (POA). We reassessed the origin of hippocampal SST interneurons using a range of genetic ...[more]

PMID: 31631021

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