摘要:

AbstractMale sexual behavior of the black cutwormAgrotis ipsilonis controlled by corpora allata. Allatectomies performed on day‐1 and day‐3 males inhibited the typical sexual behavior in day‐4 males when exposed to female pheromone in a wind tunnel. Both JH‐III and JH‐III acid were able to restore male sexual behavior, suggesting that corpora allata act through their endocrine activity. We demonstrated that corpora allata incubated in vitro produced only the acid form of JH‐III and JH‐II. Fluvastatin, an HMG‐CoA reductase inhibitor, inhibited JH acid biosynthesis by the corpora allata when fluvastatin was added to incubation medium or injected in males 4 h before the bioassay. However, endocrine activity of CA resumed 5–6 h after injection, indicating that the effect of fluvastatin was temporary. Fluvastatin injection also induced temporary inhibition of male responsiveness. © 19

ISSN:0739-4462    

DOI:10.1002/(SICI)1520-6327(1996)32:3/4<601::AID-ARCH31>3.0.CO;2-E

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractEarlier work had shown that JH acts on the membrane of the follicle cell ofLocusta migratoria,bringing about a rapid reduction in volume which can be detected in vitro by measuring the increase in optical path difference using quantitative interference microscopy. The juvenoid fenoxycarb, a phenoxyphenyl derivative, is unrelated in structure to the juvenile hormones (which are derivatives of farnesoic acid), but it also caused a reduction in volume of the cells in vitro as measured by an increase in the optical path difference. The vertebrate hormone thyroxine, and thyronine, the non‐iodinated derivative of thyroxine, also phenoxy phenyl compounds, evoked a response like fenoxycarb. The effect of thyroxine was abolished by ouabain, which inhibits Na+/K+ATPase, the effector molecule for JH, and inhibited by ethoxyzolamide which inhibits the binding of JH to a putative membrane receptor. Triiodothyronine, the effective vertebrate hormone, acted at a lower threshold and optimum concentration, and had a greater magnitude of effect than the other compounds tested. These facts suggest that these phenoxyphenyl compounds are JH agonists and that the membrane receptor for JH may resemble a possible membrane receptor for thyroxine. © 1996 Wiley‐Liss,

ISSN:0739-4462    

DOI:10.1002/(SICI)1520-6327(1996)32:3/4<613::AID-ARCH32>3.0.CO;2-D

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractA juvenile hormone‐binding protein (JHBP) has been identified in nuclear extracts of the long hyaline tubules (LHT) from the male accessory reproductive glands ofMelanoplus sanguinipes.The protein (Mr31,000) has a high affinity for JH III, which it binds preferentially over JH I. The JHBP is absent in day 1 adult males but accumulates steadily from day 2 to 8. Treatment of males with ethoxyprecocene causes the disappearance of the JHBP, an effect that can be reversed by topical application of JH III. Thus, during sexual maturation, there is a correlation between the level of nuclear JHBP and the protein synthetic activity of the LHT. © 1996 Wiley‐Liss,

ISSN:0739-4462    

DOI:10.1002/(SICI)1520-6327(1996)32:3/4<623::AID-ARCH33>3.0.CO;2-C

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractWhen an active JH analog (methoprene or pyriproxyfen) is administered to JH‐deprived (precocene‐treated) adult female locusts, there is a delay of about 24 h before vitellogenin (Vg), the product of a JH‐dependent gene, is found in the hemolymph. If a dose of JH III or methoprene, itself too low to induce any detectable Vg, is administered 12–48 h before the inducing dose of JH analog, however, the appearance of Vg after the inducing treatment is accelerated by about 12 h. This effect is described as priming. It is proposed that priming involves the synthesis of a specific transcription factor for Vg and other JH‐dependent genes. A system suitable for testing this hypothesis is provided by transcription in locust fat body nuclear extracts, using G‐free cassettes as reporter sequences. Protein extracted from fat body of JH‐deficient (precocene‐treated) locusts transcribes from the control non‐specificAdMLpromoter but not from the promoters of the two JH target genes. Preparations from normal adult female fat body, or from that of locusts treated with precocene and later with a JH analog, on the other hand, transcribe from the promoters of the JH‐dependentVgandjhp21genes, as well as theAdMLpromoter. This demonstrates the JH‐induced appearance of a specific transcription factor. The cell‐free transcription system is suitable for further analysis of the molecular components of JH regulated transcription.

ISSN:0739-4462    

DOI:10.1002/(SICI)1520-6327(1996)32:3/4<633::AID-ARCH34>3.0.CO;2-B

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractTheMethoprene‐tolerant(Met) mutation ofDrosophila melanogasterresults in resistance to juvenile hormone (JH) or JH analogs and appears to alter JH reception during late larval development. Several alleles ofMethave been recovered from methoprene selection screens after mutagenesis with ethyl methanesulfonate, X‐rays, or transposable genetic elements. The phenotype of flies carrying any of these alleles is similar—resistance to the toxic and morphogenetic effects of methoprene—but otherwise is essentially wild‐type. Understanding the function of theMetgene requires that we know whether these alleles are hypomorphic, producing some functional gene product, or amorphic, producing no functional gene product. This determination was made by comparing the methoprene‐resistance phenotype produced by representativeMetalleles with that produced by a chromosome carrying a deficiency that deletes theMetgene. The level of resistance to either the toxic or the morphogenetic effect of methoprene was similar among flies heterozygous for either the deficiency chromosome or for any of the alleles. The results provide genetic evidence that theMetalleles recovered to date are amorphic and suggest that theMetgene may not be mutable to a more severeMetallele that affects the viability, development, or reproduction of the flies. © 1996 Wil

ISSN:0739-4462    

DOI:10.1002/(SICI)1520-6327(1996)32:3/4<641::AID-ARCH35>3.0.CO;2-A

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractDifferent juvenile hormone mimics were compared regarding their efficacy against larval and pupal stages of the dipteraAedes aegypti, Musca domestica,andLucilia cuprinaas well as the cat fleaCtenocephalides felis.Structure‐activity relationship of a series of new diphenylethers was analyzed and compared to juvenoids like methoprene, hydroprene, and fenoxycarb. Selected compounds were taken for a competition binding assay and their effect on JH‐degradation by esterases was examined. The results indicate that neither high affinity to JH‐binding proteins nor interference with JH breakdown are responsible for the extraordinary efficacy of the diphenylethers investigated. Two superior diphenylethers, however, proved to be more resistant to UV‐radiation than methoprene. © 1996 Wiley

ISSN:0739-4462    

DOI:10.1002/(SICI)1520-6327(1996)32:3/4<651::AID-ARCH36>3.0.CO;2-9

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

摘要:

AbstractApplying the proinsecticide principle developed earlier for neurotoxic carbamate insecticides, a series of newN‐sulfenylated,N‐sulfinylated, andN‐sulfonylated derivatives of fenoxycarb were synthesized and evaluated for juvenile hormone mimicking activity. Laboratory evaluations of the compounds usingPieris brassicaeandSitophilus oryzae,as well as field experiments usingBemisia tabaci,showed that several symmetricalbiscarbamates with either a sulfenyl or sulfinyl bridge possessed higher activity than the parent carbamate. From the unsymmetrical compounds containing biologically inert derivatizing moieties, one of the sulfenylatedbiscarbamates also showed improved activity againstP. brassicae.The changes in the biological activity of the sulfur‐containing derivatives compared to that of the parent compound are attributed to the modified physicochemical characteristics, i.e., increased lipophilicity facilitating penetration, transport, as well as protection of the compound from metabolism. © 1996 Wiley

ISSN:0739-4462    

DOI:10.1002/(SICI)1520-6327(1996)32:3/4<659::AID-ARCH37>3.0.CO;2-9

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY

ISSN:0739-4462    

DOI:10.1002/1520-6327(1996)32:3/4<::AID-ARCH940320301>3.0.CO;2-L

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1996

数据来源: WILEY