Degenerative abnormalities in transgenic neocortical neuropeptide Y interneurons expressing tau-green fluorescent protein

Abstract : The introduction of a reporter gene into bacterial artificial chromosome (BAC) constructs allows a rapid identification of the cell type expressing the gene of interest. Here we used BAC transgenic mice expressing a tau-sapphire green fluorescent protein (GFP) under the transcriptional control of the neuropeptide Y (NPY) genomic sequence to characterize morphological and electrophysiological properties of NPY-GFP interneurons of the mouse juvenile primary somatosensory cortex. Electrophysiological whole-cell recordings and biocytin injections were performed to allow the morphological reconstruction of the recorded neurons in three dimensions. Ninety-six recorded NPY-GFP interneurons were compared with 39 wild-type (WT) NPY interneurons, from which 23 and 19 were reconstructed, respectively. We observed that 91% of the reconstructed NPY-GFP interneurons had developed an atypical axonal swelling from which emerge numerous ramifications. These abnormalities were very heterogeneous in shape and size. They were immunoreactive for the microtubule-associated protein tau and the lysosomal-associated membrane protein 1 (LAMP1). Moreover, an electron microscopic analysis revealed the accumulation of numerous autophagic and lysosomal vacuoles in swollen axons. Morphological analyses of NPY-GFP interneurons also indicated that their somata were smaller, their entire dendritic tree was thickened and presented a restricted spatial distribution in comparison with WT NPY interneurons. Finally, the morphological defects observed in NPY-GFP interneurons appeared to be associated with alterations of their electrophysiological intrinsic properties. Altogether, these results demonstrate that NPY-GFP interneurons developed dystrophic axonal swellings and severe morphological and electrophysiological defects that could be due to the overexpression of tau-coupled reporter constructs.
Complete list of metadatas

Cited literature [62 references]  Display  Hide  Download

https://www.hal.inserm.fr/inserm-02126241
Contributor : Armelle Rancillac <>
Submitted on : Saturday, May 11, 2019 - 10:11:46 AM
Last modification on : Thursday, July 4, 2019 - 11:00:07 AM

File

 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : jamais

Please log in to resquest access to the document

Identifiers

Citation

Armelle Rancillac, Jeanne Lainé, Quentin Perrenoud, Hélène Geoffroy, Isabelle Ferezou, et al.. Degenerative abnormalities in transgenic neocortical neuropeptide Y interneurons expressing tau-green fluorescent protein. Journal of Neuroscience Research, Wiley, 2009, 88 (3), pp.487-99. ⟨10.1002/jnr.22234⟩. ⟨inserm-02126241⟩

Share

Metrics

Record views

91