FIGURE 1.

The uENF1-uENF2-PP tricistronic mRNA is highly expressed during embryogenesis. A, Northern blot analysis of embryonic and larval mRNAs using a portion of the PP ORF as the DNA probe is shown. Embryonic and first larval mRNAs were prepared from the pnd-w1 strain, and fourth and fifth larval mRNAs were prepared from the C145 x N140 strain. B, 5′-RACE analysis of embryonic and larval mRNAs using a reverse primer that was designed based on the nucleotide sequence of the PP ORF is shown. All mRNAs, except that from day 2 embryo, was prepared from the C145 x N140 strain. Cloning and sequence analysis confirmed that the longer fragment derived from the 1.5-kb uENF1-uENF2-PP tricistronic mRNA, and the shorter fragment was derived from the 0.6-kb PP monocistronic mRNA.