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Biology subjects

Rieckher, M.

Publications and source records attributed to Rieckher, M..

2 recordsLinked to original sources

Neuronal DNA repair mediates systemic mitochondrial maintenance through acetylcholine signaling

DNA repair defects such as Nucleotide Excision Repair (NER) mutations can lead to progeroid syndromes characterized by growth retardation and accelerated aging with distinct tissue type specific pathologies. DNA damage induced dysfunction of specific cell types can impair the organisms overall function. It is unknown whether, in reverse, DNA repair in specific tissues can have non-cell-autonomous consequences on other tissues carrying DNA damage. To explore the organismal consequences of cell type specific DNA repair, we restricted NER activity to specific tissues and monitored consequences on organismal health in C. elegans. Unexpectedly, we observed that tissue specific DNA repair is sufficient to improve overall DNA damage resistance. Strikingly, the sole NER activity in neurons is sufficient to provide similar overall DNA damage resistance as whole body NER. We show that this systemic DNA damage resilience is mediated by neuronal Acetylcholine signaling that promotes the maintenance of mitochondrial activity throughout the organism.

genetics↗

Endogenous formaldehyde scavenges cellular glutathione resulting in cytotoxic redox disruption

Formaldehyde (FA) is a ubiquitous endogenous and environmental metabolite that is thought to exert cytotoxicity through DNA and DNA-protein crosslinking. We show here that FA can cause cellular damage beyond genotoxicity by triggering oxidative stress, which is prevented by the enzyme alcohol dehydrogenase 5 (ADH5/GSNOR). Mechanistically, we determine that endogenous FA reacts with the redox-active thiol group of glutathione (GSH) forming S-hydroxymethyl-GSH, which is metabolized by ADH5 yielding reduced GSH thus preventing redox disruption. We identify the ADH5-ortholog gene in Caenorhabditis elegans and show that oxidative stress also underlies FA toxicity in nematodes. Moreover, we show that endogenous GSH can protect cells lacking the Fanconi Anemia DNA repair pathway from FA, which might have broad implications for Fanconi Anemia patients and for healthy BRCA2-mutation carriers. We thus establish a highly conserved mechanism through which endogenous FA disrupts the GSH-regulated cellular redox homeostasis that is critical during development and aging.

cell biology↗