<i>Dcp2</i> mutant flies fail to develop cNILH.

<p>A. Diagram of the <i>Dcp2</i> genomic region with gene direction. The red vertical arrows indicate the P-element insertion sites of the <i>Dcp2^V1194</i>, <i>Dcp2^c02419</i>, and <i>Dcp2^e00034</i> mutant alleles. B–C. Total RNA extracted from fly bodies was analyzed for <i>dbo, nAChR-α96Ab</i> and <i>Dcp2</i> mRNA levels by relative qPCR. The mRNA levels of the tested genes were normalized to <i>rp49</i> mRNA. (B) The mRNA levels of <i>dbo and nAChR-α96Ab</i> were not altered in the <i>Dcp2^V1194</i> flies compared to the <i>w¹¹¹⁸</i> flies (three independent experiments, N.S., P>0.05, <i>t</i>-test). (C) <i>Dcp2</i> mRNA levels were reduced in both <i>Dcp2^V1194</i> and <i>Dcp2^V1194/e00034</i> flies (***P<0.001) but not in <i>Dcp2^c02419</i> flies (N.S., P>0.05), compared to <i>w¹¹¹⁸</i> flies. Three independent experiments were performed, one-way ANOVA. D. The locomotor activity of flies treated with nicotine-containing or control food for 4 days was recorded on the 4^th day. Total locomotor activity (TLA) data shows cNILH in heterozygous mutant <i>Dcp2^V1194/+</i>, <i>Dcp2^c02419/+</i>, and <i>Dcp2^e00034/+</i> flies (**P<0.01), but not in trans-heterozygous mutant <i>Dcp2^V1194/e00034</i> and homozygous mutant <i>Dcp2^c02419</i> flies (N.S., P>0.05) (Mann-Whitney U test). <i>Dcp2^c02419</i> flies showed significantly decreased TLA (*P<0.05). Basal TLA of <i>Dcp2^V1194/e00034</i> flies was significantly higher than that of <i>Dcp2^V1194/+</i> or <i>Dcp2^e00034/+</i> flies (*P<0.05), but comparable in <i>Dcp2^c02419</i> and <i>Dcp2^c02419/+</i> flies (N.S., P>0.05) (One-way ANOVA). n = 28–32. N.S. indicates no significant difference. Bars and error bars represent the mean ± SEM.