Document Type

Article - On Campus Only

Publication Date



The Caenorhabditis elegans nuc-1 gene has previously been implicated in programmed cell death due to the presence of persistent undegraded apoptotic DNA in nuc-1 mutant animals. In this report, we describe the cloning and characterization of nuc-1, which encodes an acidic nuclease with significant sequence similarity to mammalian DNase II. Database searches performed with human DNase II protein sequence revealed a significant similarity with the predicted C. elegans C07B5.5 ORF. Subsequent analysis of crude C. elegans protein extracts revealed that wild-type animals contained a potent endonuclease activity with a cleavage preference similar to DNase II, while nuc-1 mutant worms demonstrated a marked reduction in this nuclease activity. Sequence analysis of C07B5.5 DNA and mRNA also revealed that nuc-1(e1392), but not wild-type animals contained a nonsense mutation within the CO7B5.5 coding region. Furthermore, nuc-1 transgenic lines carrying the wild-type C07B5.5 locus demonstrated a complete complementation of the nuc-1 mutant phenotype. Our results therefore provide compelling evidence that the C07B5.5 gene encodes the NUC-1 apoptotic nuclease and that this nuclease is related in sequence and activity to DNase II.

Recommended Citation

Lyon CJ, Evans CJ, Bill BR, Otsuka AJ, Aguilera RJ. The C. elegans apoptotic nuclease NUC-1 is related in sequence and activity to mammalian DNase II. Gene. 2000 Jul 11;252(1-2):147-54. doi: 10.1016/s0378-1119(00)00213-4. PMID: 10903446.