Osmostress-Induced Apoptosis in Xenopus Oocytes

Hyperosmotic shock induces cytochrome c release and capase-3 activation in Xenopus oocytes, but the regulators and signaling pathways involved are not well characterized. Here we show that hyperosmotic shock induces rapid calpain activation and high levels of Smac/DIABLO release from the mitochondri...

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Detalles Bibliográficos
Autores: Ben Messaoud, Nabil, Yue, Jicheng, Valent, Daniel|||0000-0001-6927-3099, Katzarova, Ilina, López Blanco, José Manuel|||0000-0002-4104-6262
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:170666
Acceso en línea:https://ddd.uab.cat/record/170666
https://dx.doi.org/urn:doi:10.1371/journal.pone.0124482
Access Level:acceso abierto
Palabra clave:Xenopus oocytes
Apoptosis
Mitochondria
Oocytes
Osmotic shock
Phosphorylation
Protein kinases
Cytosol
Descripción
Sumario:Hyperosmotic shock induces cytochrome c release and capase-3 activation in Xenopus oocytes, but the regulators and signaling pathways involved are not well characterized. Here we show that hyperosmotic shock induces rapid calpain activation and high levels of Smac/DIABLO release from the mitochondria before significant amounts of cytochrome c are released to promote caspase-3 activation. Calpain inhibitors or EGTA microinjection delays osmostress-induced apoptosis, and blockage of Smac/DIABLO with antibodies markedly reduces cytochrome c release and caspase-3 activation. Hyperosmotic shock also activates the p38 and JNK signaling pathways very quickly. Simultaneous inhibition of both p38 and JNK pathways reduces osmostress-induced apoptosis, while sustained activation of these kinases accelerates the release of cytochrome c and caspase-3 activation. Therefore, at least four different pathways early induced by osmostress converge on the mitochondria to trigger apoptosis. Deciphering the mechanisms of hyperosmotic shock-induced apoptosis gives insight for potential treatments of human diseases that are caused by perturbations in fluid osmolarity.