Differential gene expression in Perillus bioculatus nymphs fed a suboptimal artificial diet.

Fragments of two artificial diet up-regulated and two prey up-regulated transcripts were isolated from the predatory Pentatomid Perillus bioculatus using suppression subtractive hybridization. A BlastX search found similarities for two diet-upregulated clones, i.e., the tyrosine-3-monooxygenase gene and the gene for the chitin binding protein, Gasp. The probe generated from the tyrosine-3-monooxygenase clone hybridized to two transcripts 2.3 and 1.2kb in size. The two transcripts were differentially regulated: the 2.3kb transcript was upregulated in the first and late third instar diet-fed nymphs, whereas the 1.2kb transcript was upregulated in the second and early third instar diet-fed nymphs. The Gasp gene was upregulated in late third instar nymphs. A positive correlation was found between levels of expression of the isolated genes and the number of generations the insects had been reared on the artificial diet.