Degradation of juvenile hormone and methylation of juvenile hormone acid by corpora cardiaca–corpora allata of the cockroach, <i>Nauphoeta cinerea</i>: I. Biochemical aspects

Meyer, Walter R.; Lanzrein, Beatrice

doi:10.1002/arch.940100406

Cited by 8 publications

(2 citation statements)

References 28 publications

(34 reference statements)

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“…In Gryllus bimncufatus, Wennauer et al [32] found that CA from adult females exhibited rates of in vitro JH I11 biosynthesis which were closely correlated with oocyte maturation. In N. cinerea, rapid degradation to the JH 111 acid was found at the very end of pregnancy [18,19]. These observations support a strong reduction of JH I11 in the hemolymph of A. thalassinus shortly before oviposition.…”

Section: Discussionsupporting

confidence: 65%

Changes in the size of corpora allata, in the juvenile hormone III titer in the hemolymph, and in the protein content of terminal oocytes throughout the first gonadotropic cycle in Aiolopus thalassinus (Insecta: Orthoptera: Acrididae)

Schmidt¹,

Othman²

1993

Arch Insect Biochem Physiol

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In Aiolopus thalassinus (Fabr.), the changes i n thevolume of the corpora aiiata (CA), in the concentration of juvenile hormone Ill (JH Ill) in the hernolymph, and i n protein content i n the terminal (t) oocytes were studied during the first gonadotropic cycle. These parameters could be better related to the volume of t-oocytes than to age after emergence. TheJH Ill titer curve was maximum (2.9 pmol/lO pl) at an oocyte volume of 1.2 mm'. Before oviposition (days 10-1 6) the JH Ill titer decreased to 0.65 prnolil0 pI hemolymph. The increase i n JH Ill titer reflected a period of high protein storage in the t-oocytes. The largest volume of the CA was reached at the beginning of yolk storage in the t-oocytes. The highest JH I11 titer did not correspond with the largest volume of CA, which occurred much earlier. o 1993 ~i l e y -~i s s , Inc.

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Section: Discussionsupporting

confidence: 65%

Changes in the size of corpora allata, in the juvenile hormone III titer in the hemolymph, and in the protein content of terminal oocytes throughout the first gonadotropic cycle in Aiolopus thalassinus (Insecta: Orthoptera: Acrididae)

Schmidt¹,

Othman²

1993

Arch Insect Biochem Physiol

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“…Supporting the hypothesis that interaction between the carrier and hydrolytic enzymes can affect the relative abundance of natural JH isoforms is the observation that interaction between caiTiers and JHEs can result in preferential hydrolysis of one optical isomer of JH from experimental racemic mixes. Whether the physiological or non-physiological isomer is hydrolysed depends on whether the carrier or the esterase has the greater selectivity between isomers (Peter et al, 1979;de Kort et al, 1983;Schooley et al, 1984;Meyer and Lanzrein, 1989).…”

Section: Interactions Among Carrier Binding Synthesis and Degradation Of Jh Isoformsmentioning

confidence: 99%

Characterisation of juvenile hormone esterase in Drosophila melanogaster

Campbell

Healy

Oakeshott

1992

Insect Biochemistry and Molecular Biology

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Juvenile hormone (JH) is one of the main morphogenic hormones of insects and degradation of the hormone is believed to play an important role in its regulation in many insects. The two main routes for JH degradation are hydroy sis by JH esterase (JHE) and JH epoxide hydrolase (JHEH). • A major focus of research has been on juvenile hormone esterase (JHE) found in the haemolymph of final instar lepidopteran larvae, although considerable hydrolysis of JH occurs in other tissues and at other life stages. In contrast, no comprehensive study of JH degradation has been undertaken in any dipteran species. However, the available evidence suggests that very little JH degrading activity is found in the haemolymph of Diptera and several dipteran JHEs exhibit atypical patterns of sensitivity to inhibitors. These data suggested that both the expression pattern and the biochemical properties of dipteran JH degrading enzymes may differ from other insect orders, and therefore, that the role of JH degradation may be different.The aim of this project was to comprehensively characterise JH degradation in the dipteran, Drosophila melanogaster, with special emphasis on JHE. The first objective was to identify the JH degrading enzymes of D . melanogaster and the second was to deterrnine their expression patterns and biochemical properties in order to determine thei~ role in the regulation of JH titre. These data were compared with other data to deterrnine whether a general model could be developed for dipteran JH titre regulation. Finally, the roles of JH hydrolysis in the regulation of JH titre were compared among Diptera, Lepidoptera and other insects.Two approaches were taken to identify the JH degrading enzymes of D. melanogaster. The first was to investigate the properties of an esterase, denoted EST20, which can be visualised after native polyacrylarnide gel electrophoresis using artificial esterase substrates, a-and B-naphthylacetate. EST20 is shown to be a likely homologue of the p-esterase of Drosophila virilis, which has been claimed to be the JHE of this species. However, this study shows that JH hydrolytic activity is associated with neither EST20 in D. melanogaster nor the p-esterase in D . virilis.The second approach was to use a radiometric assay which identified two JH hydrolysing enzymes, JHE and JHEH. The developmental profile of JH hydrolytic activity in D. melanogaster correlates inversely with profiles of JH titre and production. Key features are prewandering and prepupal maxima of JH hydrolytic activity in whole body homogenates of final instar larvae. This developmental profile of expression is similar to the lepidopteran pattern suggesting that the role of JH hydrolysis is essentially similar during this period. In D. melanogaster, the prewandering maximum consists mainly of JHEH whereas the prepupal peak consists mainly of JHE. However, the relative contributions of JHE and JHEH at these times differs both among the Diptera and in other orders.JHE from the prepupal stage was purified to homogeneity by selectiv...

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Degradation of juvenile hormone and methylation of juvenile hormone acid by corpora cardiaca–corpora allata of the cockroach, Nauphoeta cinerea: II. Physiological aspects

Meyer

Lanzrein

1989

Arch Insect Biochem Physiol

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In vitellogenic females of Nauphoeta cinerea, injected (lOR)-juvenile hormone (JH) I l l was degraded more rapidly than racemic JH 111: we measured a halflife of 21 min (with or without coinjection of lipophorin) for the former and 24 min (with coinjection of lipophorin) and 43 min (without coinjection of lipophorin) for the latter. One to two hours after injection, JH I l l acid was the major metabolite observed; in addition, several highly polar products were found. The half-life of injected racernic JH I l l acid was 19 rnin with coinjection of lipophorin and 4 rnin without. The JH I l l acid titer in hemolymph was low (around 5-10 pmol/ml) in last instar larvae and previtellogenic and pregnant females and reached higher values (40-100 pmol/ml) in vitellogenic and ovulating females. Racernic JH Ill acid could be methylated in vitro to J H Ill by corpora cardiaca-corpora allata (CC-CA) from penultimate instar larvae and females at stages between adult ecdysis and ovulation and at the very end of pregnancy, but not by CC-CA from last instar larvae and adult females at earlier stages of pregnancy. This indicates that CC-CA are capable of methylating JH Ill acid only at stages when JH Ill i s detectable in the hemolymph. In doublelabelling experiments with CC-CA from vitellogenic females and L-[l4CImeth-ionine and [3H]JH I l l acid as precursors, we observed that only a small proportion (I-8%) of total biosynthesized J H Ill was derived from JH Ill acid when the latter was present at physiological concentration. This suggests that in vivo recycling of JH Ill acid-by CC-CA plays only a minor role in the regulation of the titer of JH Ill and JH Ill acid.

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Degradation of juvenile hormone and methylation of juvenile hormone acid by corpora cardiaca–corpora allata of the cockroach, Nauphoeta cinerea: I. Biochemical aspects

Cited by 8 publications

References 28 publications

Changes in the size of corpora allata, in the juvenile hormone III titer in the hemolymph, and in the protein content of terminal oocytes throughout the first gonadotropic cycle in Aiolopus thalassinus (Insecta: Orthoptera: Acrididae)

Changes in the size of corpora allata, in the juvenile hormone III titer in the hemolymph, and in the protein content of terminal oocytes throughout the first gonadotropic cycle in Aiolopus thalassinus (Insecta: Orthoptera: Acrididae)

Characterisation of juvenile hormone esterase in Drosophila melanogaster

Degradation of juvenile hormone and methylation of juvenile hormone acid by corpora cardiaca–corpora allata of the cockroach, Nauphoeta cinerea: II. Physiological aspects

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