We use C. elegans as a model organism to study the impact of NAD+ metabolism on development. We have identified a delayed-hatching phenotype associated with deficiency in the nmrk-1 gene, which is involved in NAD+ biosynthesis. We examined deficiency in the genes nmat-1 and nmat-2, which operate directly downstream of nmrk-1. Through mutant analysis and RNAi knockdowns, we have found that a similar, possibly more severe phenotype is associated with deficiency in the nmat genes.