Dna2 Requirement for Normal Reproduction of Caenorhabditis Elegans is Temperature-dependent

To determine the function of Dna2 in a multicellular organism, the Caenorhabditis elegans Dna2 expression was probed and deletion mutant phenotypes were analyzed. Dna2 was localized to the nuclei of C. elegans oocytes and early embryos by immunostaining or green fluorescent protein-tagging. A homozygous dna2 deletion mutant showed a reduced brood size and embryonic lethality, and the phenotypes greatly depended on growth temperature and aggravated in the succeeding generation. The mutant embryos also showed delayed cell divisions, which together with temperature-dependence of the mutant phenotypes supported the well-conserved role of Dna2 in DNA replication.