FIGURE 1.

RNA interference with the CeNXT1/p15 gene results in embryonic lethality. (A) Sequence comparison between human and C. elegans NXT1 proteins, and between human and C. elegans NTF-2 proteins. Sequences were compared using the GAP program (GCG10 software), and output was produced using PRETTYBOX (GCG10 software). Identical residues are highlighted in black. The dsRNA fragments used for RNAi correspond to the regions marked by the arrows below and above the sequences, respectively. (B) RNA interference with the CeNXT1/p15 gene leads to early embryonic lethality (a–c). Wild-type embryo developmental stages (d) gastrulated, (e) beginning of morphogenesis, (f) comma are shown for comparison. Each embryo is ~50 μm in length. (C) The effectiveness of RNAi was determined by examining the level of the residual transcripts following dsRNA injections by RT–PCR with specific primers, as described previously (Longman et al. 2000). CeNXT1/p15 mRNA is specifically depleted in RNAi-treated animals (lane 4) compared with wild-type animals (lane 2); whereas the level of a control mRNA, corresponding to CeNXF1/Tap1, is unaffected (lanes 1,3). The figure shows a negative of an ethidium bromide-stained agarose gel. (M) 100-bp ladder DNA size marker.