Insect Biochemistry最新文献

{"title":"Structure of the ecdysone glucoside formed by a baculovirus ecdysteroid UDP-glucosyltransferase","authors":"David R. O'Reilly , Oliver W. Howarth , Huw H. Rees , Lois K. Miller","doi":"10.1016/0020-1790(91)90121-T","DOIUrl":"https://doi.org/10.1016/0020-1790(91)90121-T","url":null,"abstract":"","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 7","pages":"795-801"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90121-T","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72261733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expression from two Drosophila promoters in embryos of the migratory locust","authors":"Swarna K. Mathi,&nbsp;Virginia K. Walker,&nbsp;Gerard R. Wyatt","doi":"10.1016/0020-1790(91)90032-A","DOIUrl":"10.1016/0020-1790(91)90032-A","url":null,"abstract":"<div><p>We have accomplished gene transfer into embryos of <em>Locusta migratoria</em>, the African migratory locust. Freshly oviposited eggs were injected with circular or linear plasmids containing the <em>Drosophila</em> hsp70 promoter and the choramphenicol acetyltransferase (CAT) reporter gene (hsp-cat), or with circular plasmid containing the <em>Drosophila</em> copia promoter fused to CAT (copia-cat). Southern blot analysis showed that the hsp-cat plasmid persisted extrachromosomally for at least 8 days after injection. There was no evidence for plasmid replication. Transient expression from the introduced promoters was determined by monitoring CAT enzyme activity. After injection of hsp-cat, activity was detected at varying levels in 6–8% of day 3 and day 9 embryos. Embryos injected with copia-cat, assayed on day 3, had a greater frequency but no higher level of expression. The described gene transfer system is promising for analysis of other promoters, including those of <em>Locusta</em>.</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 6","pages":"Pages 623-629"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90032-A","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86284837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glutathione S-transferase activities in phytophagous insects: Induction and inhibition by plant phototoxins and phenols","authors":"Keywan Lee","doi":"10.1016/0020-1790(91)90001-U","DOIUrl":"10.1016/0020-1790(91)90001-U","url":null,"abstract":"<div><p>The effects of two plant phototoxins (xanthotoxin and harmine) and three plant phenols (quercetin, ellagic acid, and juglone) on detoxification enzymes were studied in the polyphagous cabbage looper, <em>Trichoplusia ni</em>, and the oligophagous black swallowtail, <em>Papilio polyxenes</em>. In <em>P. polyxenes</em>, glutathione <em>S</em>-transferase (GST) activities toward 1-chloro-2,4-dinitrobenzene (CDNB) were 1840 and 1750 nmol CDNB conjugate/mg protein/min in the cytosolic fraction of midgut and fat body, respectively. Dietary xanthotoxin (0.1% fw) increased the activity 2.5 and 2.9-fold in the midgut and fat body, respectively. Xanthotoxin-conjugating GST activity was absent in both tissues. In <em>T. ni</em>, GST activity, 513 nmol CDNB conjugate/mg protein/min in the cytosolic fraction of midgut, was increased almost twofold by dietary xanthotoxin and harmine. Plant phenols effectively inhibited <em>in vitro</em> GST and Se-independent glutathione peroxidase (GPOX) activities in a dose-dependent manner in the two species. Both GST and GPOX of <em>P. polyxenes</em> were 2-fold less sensitive to phenol inhibitors than <em>T. ni</em>. GST inhibition differed according to the nature of the inhibitor in <em>P. polyxenes</em>. Quercetin is competitive with CDNB and is non-competitive with respect to GSH. In contrast, inhibition by ellagic acid is non-competitive with CDNB and competitive with GSH. Juglone showed competitive inhibition with both GSH and CDNB.</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 4","pages":"Pages 353-361"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90001-U","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78923083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Production of farnesoic acid and methyl farnesoate by mandibular organs of the crayfish, Procambarus clarkii","authors":"Q. Ding,&nbsp;S.S. Tobe","doi":"10.1016/0020-1790(91)90018-A","DOIUrl":"10.1016/0020-1790(91)90018-A","url":null,"abstract":"<div><p>The mandibular organs (MO) of crustaceans secrete methyl farnesoate (MF) and farnesoic acid (FA). To better understand the secretory activity of MO, the kinetics of production and release of both compounds were determined <em>in vitro</em> by following incorporation of [2-¹⁴C]acetate and <span>l</span>-[³H-methyl]methionine into MF and [2-¹⁴C]acetate into FA by MO of <em>Procambarus clarkii</em>. MO released more FA than MF but contained more MF. In medium lacking unlabeled acetate, the percentage incorporation of [¹⁴C]acetate into MF, relative to [³H]methionine, was between 21 and 40%, suggesting that there may be an alternative source of C₂ units.</p><p>MO produce similar amounts of MF at concentrations of acetate from 0.08 to 10 mM. However, the addition of exogenous unlabelled FA to incubation media did not stimulate the biosynthesis of MF, raising the possibility that unlike JH biosynthesis in insects, the last step in MF production may be rate-limiting. Nonetheless, exogenous FA significantly reduced the incorporation of [¹⁴C]acetate into MF, suggesting that the glands use exogenous FA to synthesize MF. The absence of stimulation of FA production by exogenous FA indicates that there is no feedback effect of this product on the early steps in the biosynthetic pathway.</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 3","pages":"Pages 285-291"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90018-A","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74638744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Properties of glycosidases from the maize weevil, Sitophilus zeamais","authors":"J.E. Baker","doi":"10.1016/0020-1790(91)90031-9","DOIUrl":"10.1016/0020-1790(91)90031-9","url":null,"abstract":"<div><p>A survey of glycosidase activity in adults of the maize weevil, <em>Sitophilus zeamais</em> Motschulsky, indicated a complex of enzymes qualitatively sufficient to hydrolyze the free di- and oligosaccharides in their cereal diets as well as the maltose and oligomaltodextrins produced by the action of α-amylase on ingested starch. Glycosidase activity was found primarily in the soluble fraction (105,000 <em>g</em> supernatant) of gut (foregut, midgut and contents) homogenates and was most active in buffers with slightly acidic pH. α-Glucosidase activity was detected by using <span><math><mtext>p-</mtext><mtext>nitrophenyl</mtext><mtext>-α-</mtext><mtext>d</mtext><mtext>-glucopyranoside</mtext></math></span> (NPαGlu), maltose, sucrose and melezitose as substrates. Based on differences in pH optima, there may be a specific α-trehalase. β-Glucosidase activity was detected with <span><math><mtext>p-</mtext><mtext>nitrophenyl</mtext><mtext>-β-</mtext><mtext>d</mtext><mtext>-glucopyranoside</mtext></math></span> and cellobiose. <span><math><mtext>p-</mtext><mtext>Nitrophenyl</mtext><mtext>-α-</mtext><mtext>d</mtext><mtext>-galactopyranoside</mtext></math></span> was not hydrolyzed but the slow hydrolysis of melibiose indicated the presence of an α-galactosidase. β-Galactosidase was detected with <span><math><mtext>p-</mtext><mtext>nitrophenyl</mtext><mtext>-β-</mtext><mtext>d</mtext><mtext>-galactopyranoside</mtext></math></span>. Raffinose was slowly hydrolyzed. The molecular mass of α-glucosidase, partially purified from adult weevils by ammonium sulfate precipitation and ion exchange chromatography, was estimated to be 130 kDa under non-dissociating conditions. α-Glucosidase activity was detected at <em>R</em>_m 0.43 on 7.5% acrylamide gels with 4-methyl-umbelliferyl-α-<span>d</span>-glucoside as substrate. pI was estimated to be 4.9 by isoelectric focusing. Two fractions with activity against <span><math><mtext>p-</mtext><mtext>nitrophenyl</mtext><mtext>-α-</mtext><mtext>d</mtext><mtext>-glucopyranoside</mtext></math></span> were resolved by high performance liquid chromatography. One fraction (peak No. 2) was highly specific for maltose, had <em>K</em>_m values of 12.9 mM for NPαGlu and 14 mM for maltose, and hydrolyzed oligomaltodextrins up to at least maltoheptaose</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 6","pages":"Pages 615-621"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90031-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90162607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reverse endocrinology, or “hormones” seeking functions","authors":"Rene Lafont","doi":"10.1016/0020-1790(91)90112-R","DOIUrl":"10.1016/0020-1790(91)90112-R","url":null,"abstract":"<div><p>Traditionally, endocrinologists have discovered hormones by identifying, thanks to a suitable bioassay, which effectors are involved in the control of a given biological function. By contrast, “Reverse Endocrinologists” first obtain the evidence for “hormones” by using available biochemical methods, and then try to determine what their function may be, usually by analogy with what has been formerly established in other animal groups by “Classical Endocrinologists”.</p><p>This problem is exemplified by ecdysteroids and vertebrate-type steroids, that are widespread among invertebrates. In many cases, it is not known whether these compounds are endogenously synthesized or if they originate from the food. Little is known concerning their possible hormonal functions, with the exception, of course, of ecdysteroids in Arthropods, where they were originally discovered.</p><p>Up to now, searching for the possible hormonal function of molecules isolated with “heterologous” tools, i.e. performing “reverse endocrinology”, has appeared a disappointing approach for the identification of physiological regulators.</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 7","pages":"Pages 697-721"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90112-R","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76306235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cuticle proteins of the boll weevil, Anthonomus grandis, abdomen: Structural similarities and glycosylation","authors":"Brad Stiles","doi":"10.1016/0020-1790(91)90014-6","DOIUrl":"10.1016/0020-1790(91)90014-6","url":null,"abstract":"<div><p>Cuticle proteins are thought to be important in defining the structural and functional differences occurring in insect cuticle. In order to explain and better understand the structural similarities among the cuticle proteins of the cotton boll weevil, <em>Anthonomus grandis</em> Boheman, described in a previous study (Stiles and Leopold, 1990, <em>Insect Biochem.</em><strong>20</strong>, 113–125) three series of monoclonal antibody producing hybridoma cell lines were produced. Larval, pupal or adult cuticle proteins were used as antigens. While some of the monoclonal antibodies were specific for one or two cuticle proteins from a single developmental stage, the majority showed multiple cuticle protein binding patterns on Western blots. To determine whether this cross-reaction was due to common oligosaccharide chains bound to the proteins, lectins were used to probe Western blots. Many of the cuticle proteins were found to be glycosylated. The majority of the Con A reactive carbohydrate could be removed from the protein by <em>N</em>-glycosidase F digestion (specific for <em>N</em>-asparagine linked carbohydrate). <em>N</em>-glycosidase F digestion did not reduce the multiple cross-reactions of the monoclonal antibodies, nor did periodate oxidation of the CP. The carbohydrate remaining after enzyme digestion is presumably <em>O</em>-linked to serine/threonine.</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 3","pages":"Pages 249-258"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90014-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86416185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of inhibitors and activators on the activity of two diaphorases from Drosophila virilis","authors":"T.G. Georgieva,&nbsp;B.C. Dunkov,&nbsp;K.H. Ralchev","doi":"10.1016/0020-1790(91)90044-F","DOIUrl":"10.1016/0020-1790(91)90044-F","url":null,"abstract":"<div><p>The effect of some inhibitors and activators of mammalian DT-diaphorase on diaphorase-1 (DIA-1) and diaphorase-2′ (DIA-2′) purified from <em>Drosophila virilis</em> was studied. The inhibitors and activators changed the activity of these diaphorases in a different way, revealing a similarity between mammalian DT-diaphorase and <em>D. virilis</em> DIA-1 on the one hand and on the other between the <em>D. virilis</em> DIA-1 and the diaphorase purified from <em>Bombyx mori</em> eggs. These effects also confirm the independent genetic control of DIA-1 and DIA-2′ in <em>D. virilis</em> and make possible the differentiation of these diaphorase activities in crude enzyme extracts.</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 2","pages":"Pages 145-147"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90044-F","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75879768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Incorporation of arylphorins (LSP-1) and LSP-2 like protein into the integument of Ceratitis capitata during pupariation","authors":"Sotiris Tsakas,&nbsp;Panagiotis G. Katsoris,&nbsp;Kostas Bourtzis,&nbsp;Vassilis J. Marmaras","doi":"10.1016/0020-1790(91)90104-M","DOIUrl":"10.1016/0020-1790(91)90104-M","url":null,"abstract":"<div><p>The arylphorins and LSP-2 like polypeptide were detected by immunoblotting analysis during development in the integument of <em>C. capitata</em>. <em>In vitro</em> translation of total RNA from fat body and integument during pupariation, clearly revealed that the polypeptides under consideration were exclusively synthesized in the fat body. Furthermore, <em>in vitro</em> experiments demonstrated that radiolabeled arylphorins and LSP-2 like polypeptide were taken up by the integument, in an undegraded state. Immunofluorescence experiments in cross sections of wandering stage larvae and white pupae revealed that the LSP-2 like polypeptide was mainly localized in the epidermal cells, and a very weak signal was also given by the cuticle. Furthermore, the presented results indicated that a small portion of the extracted proteins exist in high molecular weight aggregate(s).</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 5","pages":"Pages 507-515"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90104-M","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86136051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alkaline phosphatase from the excretory system of the grasshopper, Poekilocerus bufonius","authors":"Samir M. Khoja","doi":"10.1016/0020-1790(91)90012-4","DOIUrl":"10.1016/0020-1790(91)90012-4","url":null,"abstract":"<div><p>Alkaline phosphatase from the excretory system of the grasshopper, <em>Poekilocerus bufonius</em> was purified with ammonium sulphate fractionation and chromatography on Bio-Gel A-0.5 m. The specific activity of the enzyme is 152 units/mg of protein. The enzyme is a tetramer and the <em>M</em>_r value of the subunit is 72,000 ± 2500 as shown by gel filtration and SDS-polyacrylamide gel electrophoresis. The enzyme has a pH optimum of 9.6 and an apparent <em>K</em>_m value of 0.28 × 10⁻³ M. The activity of the enzyme reached a maximum at 75°C and the enzyme showed stability at 65°C. The enzyme was inhibited by Ca²⁺, Na⁺ and Fe³⁺ and was stimulated by Zn²⁺, Mn²⁺ and Mg²⁺.</p></div>","PeriodicalId":13955,"journal":{"name":"Insect Biochemistry","volume":"21 3","pages":"Pages 239-242"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0020-1790(91)90012-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77219052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}