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TOR signaling couples oxygen sensing to lifespan in C. elegans.

ABSTRACT: Metazoans adapt to a low-oxygen environment (hypoxia) through activation of stress-response pathways. Here, we report that transient hypoxia exposure extends lifespan in C. elegans through mitochondrial reactive oxygen species (ROS)-dependent regulation of the nutrient-sensing kinase target of rapamycin (TOR) and its upstream activator, RHEB-1. The increase in lifespan during hypoxia requires the intestinal GATA-type transcription factor ELT-2 downstream of TOR signaling. Using RNA sequencing (RNA-seq), we describe an ELT-2-dependent hypoxia response that includes an intestinal glutathione S-transferase, GSTO-1, and uncover that GSTO-1 is required for lifespan under hypoxia. These results indicate mitochondrial ROS-dependent TOR signaling integrates metabolic adaptations in order to confer survival under hypoxia.

SUBMITTER: Schieber M

PROVIDER: S-EPMC4194168 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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TOR signaling couples oxygen sensing to lifespan in C. elegans.

Schieber Michael M Chandel Navdeep S NS

Cell reports 20141002 1

Metazoans adapt to a low-oxygen environment (hypoxia) through activation of stress-response pathways. Here, we report that transient hypoxia exposure extends lifespan in C. elegans through mitochondrial reactive oxygen species (ROS)-dependent regulation of the nutrient-sensing kinase target of rapamycin (TOR) and its upstream activator, RHEB-1. The increase in lifespan during hypoxia requires the intestinal GATA-type transcription factor ELT-2 downstream of TOR signaling. Using RNA sequencing (R ...[more]

PMID: 25284791

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