Cloning and expression of a JHA-inducible glutathione S-transferase gene in the common cutworm Spodoptera litura (Lepidoptera: Noctuidae)

• Published in: Journal of Asia-Pacific entomology Vol. 17; no. 3; pp. 363 - 368
• Main Authors: Wu, Ming-Cheng, Lu, Kuang-Hui
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2014; 한국응용곤충학회
• Subjects: Affinity chromatography; Glutathione S-transferase; Lepidoptera; Noctuidae; Spodoptera litura; 농수해양학; Glutathione S-transferase; Affinity chromatography; Spodoptera litura
• ISSN: 1226-8615; 1876-7990
• DOI: 10.1016/j.aspen.2014.02.005

The juvenile hormone titer during the last instar is a crucial determining switch for metamorphosis in lepidopterans. We previously observed that the induction of glutathione S-transferase (GST) activity by a juvenile hormone analog (JHA) is reversely proportional to the occurrence of JHA-induced supernumerary instars following topical application of JHA to Spodoptera litura during the last instar period. In this paper, at least five JHA-induced GSTs were purified by glutathione-affinity chromatography, and one was further isolated for determination of the N-terminal sequence. The corresponding cDNA was cloned and named SlGST1 (GenBank accession no. AY506545). SlGST1 was classified into the epsilon class of GSTs by phylogenetic analysis. Northern blot analyses further showed that the SlGST1 in fat bodies can be induced by JHA, particularly in 0-day-old sixth-instar larvae, in which induction was much higher than that in 1- and 2-day-old sixth-instar larvae. To our knowledge, this is the first JHA-inducible GST to have been identified, and we believe that it will provide new insight into the role of GST in insect development, particularly during metamorphosis. Relative expression profiles of the GST, SlGST1, in 0-, 1- and 2-day-old sixth instar larvae, respectively, after treatment with 100μg JHA/larva. [Display omitted] •Juvenile hormone analog (JHA) is able to induce glutathione S-transferase (GST) activity.•At least five JHA-induced GSTs were purified by glutathione-affinity chromatography.•One of them, named SlGST1, was further isolated and classified into the epsilon class of GSTs.•Northern blot analyses showed that the SlGST1 in fat body can be induced by JHA.•This is probably the first JHA-inducible GST that was identified.