Involvement of Cyclic Nucleotide-Gated Channels in the Anoxia Response in Caenorhabditis elegans and Drosophila melanogaster

Oxygen is a key element for energy production in mitochondria, and thus the anoxic state (0% O2) is seriously deleterious for most organisms. However, Caenorhabditis elegans (C. elegans) has been known to survive anoxia for at least 48 hours. In a previous work from our lab, a new pathway involving the HYL-2 ceramide synthase was described. A mutation in the ceramide synthase gene hyl-2 triggers reduced resistance of C. elegans against anoxia (Menuz et al., 2009). Continuing this project, we tried to find a suppressor mutant of hyl-2. However, eventually we found a cng-2(gnv2) mutant which is in an independent pathway and confers a hyper resistant phenotype that survives after 72 hours of anoxia while wild type can not. In parallel, we tested down regulations of the cng-2 gene and its homologs in Drosophila melanogaster (D. melanogaster) sensory neurons. We confirmed that these flies wake up faster than control flies after 1 hour period of anoxia. These findings delineate a novel function of CNG channels, which sense environmental conditions including oxygen concentration