CLONING OF A PUTATIVE JUVENILE HORMONE-RESPONSIVE STORAGE PROTEIN GENE FROM THE TOBACCO BUDWORM, HELIOTHIS-VIRESCENS

A cDNA clone with 78% amino acid identity to a basic juvenile hormone (JH)-suppressible hemolymph protein from the cabbage looper, Trichoplu sia ni, was isolated from the tobacco budworm, Heliothis virescens. Th is clone was obtained upon screening a cDNA library derived from larva l fat body of a pesticide resistant strain of H. virescens with a cDNA probe for Drosophila melanogaster glutathione S-transferase. By compa rison with other insect storage proteins, this clone was predicted to be part of an approximately 2,300 nucleotide (nt) cDNA, of which 691 n t were isolated and sequenced. The partial cDNA clone hybridizes to a RNA of approximately 2,370 nt in H. virescens. Treatment with a juveno id (2-[1-methyl-2-(4-phenoxyphenoxy)ethoxy] pyridine; pyriproxifen) le ads to a decrease in RNA levels of this putative hemolymph storage pro tein in early fifth stadium larvae of H. virescens, prior to commitmen t. In contrast, treatment in late fifth stadium (after commitment to p upal development) leads to an increase in the RNA level of this JH-res ponsive gene. This is the first report of both induction and suppressi on of storage protein RNA levels in the same stadium. We have given th is gene the designation Hv-SP4 (H. virescens, storage protein 4; acces sion no. U48594). Genetic segregation analysis of restriction fragment length polymorphisms (RFLPs) defined by Hv-SP4 has shown that it is t he product of a single-copy, Mendelian, autosomal gene. (C) 1996 Wiley -Liss, Inc.