A novel geminal diol as a highly specific and stable in vivo inhibitor of insect juvenile hormone esterase

Juvenile hormone (JH) degradation in vitro and in vivo was studied in the viviparous cockroach Diploptera punctata. In vitro studies with juvenile hormone esterase (JHE) and "general" or 1-naphthyl acetate esterase (NAcE) revealed that diethyl-p-nitrophenylphosphate (paraoxon) inhibited both JHE and NAcE activity, but the latter was more sensitive and was completely inhibited at 0.1 mM. NAcE activity was resistant to inhibition with Triton X-100, whereas JHE activity in haemolymph of adult females was inhibited 100% at Triton X-100 concentration of 0.25%. Eighty percent inhibition of JHE activity in vivo was observed following injection of 0.2 μL Triton X-100. In contrast to the previously observed dose-dependant increase in JHE activity, NAcE activity did not increase following treatment of allatectomized females with the JH analogue ethyl-2E,4E-3,7,11-trimethyl-2,4-dodecadienoate (hydroprene). Hydroprene was not catabolized in haemolymph of D. punctata in vitro. The half-life of C16 JH (JH III) in the haemolymph, in vivo, was 1.65 h for day 5 females and 2 h for day 6 females.

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Evolutionary endocrinology of juvenile hormone esterase in Gryllus assimilis: direct and correlated responses to selection.

Genetics ◽

10.1093/genetics/141.3.1125 ◽

1995 ◽

Vol 141 (3) ◽

pp. 1125-1134 ◽

Cited By ~ 1

Author(s):

A J Zera ◽

C Zhang

Keyword(s):

Enzyme Activity ◽

Juvenile Hormone ◽

Protein Concentration ◽

Correlated Responses ◽

Hormone Metabolism ◽

Juvenile Hormone Esterase ◽

Naturally Occurring ◽

Highly Correlated ◽

Juvenile Development

Abstract Hemolymph juvenile hormone esterase (JHE) activity on the third day of the last stadium in the cricket, Gryllus assimilis, exhibited a significant response to selection in each of six replicate lines. Mean realized heritability was 0.26 +/- 0.04. The response was due to changes in whole-organism enzyme activity as well as to changes in the proportion of enzyme allocated to the hemolymph compartment. In vivo juvenile hormone metabolism differed between some lines selected for high vs. low enzyme activity. Only minimal differences were observed between lines with respect to hemolymph protein concentration or whole-cricket activity of juvenile hormone epoxide hydrolase, the other major JH-degrading enzyme. Dramatic correlated responses to selection, equal in magnitude to the direct response, were observed for JHE activity on each of three other days of the last juvenile stadium. In contrast, no correlated responses in JHE activity were observed in adults. This indicates that JHE activities throughout the last stadium will evolve as a highly correlated unit independent of adult activities and the evolution of endocrine mechanisms regulating juvenile development can be decoupled from those controlling adult reproduction. This study represents the first quantitative-genetic analysis of naturally occurring endocrine variation in an insect species.

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