Mitochondria and calcium defects correlate with axonal dysfunction in GDAP1-related Charcot-Marie-Tooth mouse model

Ganglioside-induced differentiation associated protein 1 (GDAP1) gene encodes a protein of the mitochondrial outer membrane and of the mitochondrial membrane contacts with the endoplasmic reticulum (MAMs) and lysosomes. Since mutations in GDAP1 cause Charcot–Marie–Tooth, an inherited motor and senso...

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Detalles Bibliográficos
Autores: Civera Tregón, Azahara, Benítez Iglesias, Raúl|||0000-0002-8782-9406, Hoenicka, Janet, Palau, Francesc
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/344954
Acceso en línea:https://hdl.handle.net/2117/344954
https://dx.doi.org/10.1016/j.nbd.2021.105300
Access Level:acceso abierto
Palabra clave:Neurobiology
Mitochondria
Axon
Bioenergetics
Calcium
Charcot-Marie-Tooth disease
Embryonic motor neurons
GDAP1
Neurobiologia
Neurogenètica
Mitocondris
Àrees temàtiques de la UPC::Enginyeria biomèdica
Descripción
Sumario:Ganglioside-induced differentiation associated protein 1 (GDAP1) gene encodes a protein of the mitochondrial outer membrane and of the mitochondrial membrane contacts with the endoplasmic reticulum (MAMs) and lysosomes. Since mutations in GDAP1 cause Charcot–Marie–Tooth, an inherited motor and sensory neuropathy, its function is essential for peripheral nerve physiology. Our previous studies showed structural and functional defects in mitochondria and their contacts when GDAP1 is depleted. Nevertheless, the underlying axonal pathophysiological events remain unclear. Here, we have used embryonic motor neurons (eMNs) cultures from Gdap1 knockout (Gdap1-/-) mice to investigate in vivo mitochondria and calcium homeostasis in the axons. We imaged mitochondrial axonal transport and we found a defective pattern in the Gdap1-/- eMNs. We also detected pathological and functional mitochondria membrane abnormalities with a drop in ATP production and a deteriorated bioenergetic status. Another consequence of the loss of GDAP1 in the soma and axons of eMNs was the in vivo increase calcium levels in both basal conditions and during recovery after neuronal stimulation with glutamate. Further, we found that glutamate-stimulation of respiration was lower in Gdap1-/- eMNs showing that the basal bioenergetics failure jeopardizes a full respiratory response and prevents a rapid return of calcium to basal levels. Together, our results demonstrate that the loss of GDAP1 critically compromises the morphology and function of mitochondria and its relationship with calcium homeostasis in the soma and axons, offering important insight into the cellular mechanisms associated with axonal degeneration of GDAP1-related CMT neuropathies and the relevance that axon length may have.