The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera (Hübner).The cDNA contains a 444 bp open reading frame,...The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera (Hübner).The cDNA contains a 444 bp open reading frame,encoding a protein with 147 amino acids,namely HarmOBP5.HarmOBP5 was expressed in Escherichia coli and the recombinant protein was purified by affinity chromatography.SDS-PAGE and Western blot analysis demonstrated that the purified protein can be used for further investigation of its binding characteristics.Competitive binding assays with 113 odorant chemicals indicated that HarmOBP5 has strong affinity to some special plant volatiles,including (E)-β-farnesene,ethyl butyrate,ethyl heptanoate,and acetic acid 2-methylbutyl ester.Based on three-dimensional (3D) model of AaegOBP1 from Aedes aegypti,a 3D model of HarmOBP5 was predicted.The model revealed that some key binding residues in HarmOBP5 may play important roles in odorant perception of H.armigera.This study provides clues for better understanding physiological functions of OBPs in H.armigera and other insects.展开更多
The dual-choices tests of behavioral test were used to study the gustatory behavioral responses to caffeine of Helicoverpa armigera larvae and H. assulta larvae. Electrophysiological responses were studied by electrop...The dual-choices tests of behavioral test were used to study the gustatory behavioral responses to caffeine of Helicoverpa armigera larvae and H. assulta larvae. Electrophysiological responses were studied by electrophysiological tip recording. Behavioral experiments showed that caffeine was a feeding deterrent for both larvae, but it showed a stronger feeding deterring effect on the oligophagous H. assulta . The electrophysiological tip-recording results showed that both H. armigera larvae and H. assulta larvae had one caffeine-sensitive feeding deterrent neuron at the medial sensilla, and the electrophysiological pulse response of H. assulta larvae was significantly stronger than that of H. armigera larvae. Therefore, caffeine had a stronger feeding deterring effect on the oligophagous H. assulta than the polyphagous H. armigera . The difference in behavioral effect was closely related to the sensitivity of to caffeine the feeding deterrent neurons at the medial sensilla.展开更多
Plants have evolved sophisticated defense mechanisms against herbivores to help them adapt to the environment. Understanding the defense mechanisms in plants can help us control insects in a more effective manner. In ...Plants have evolved sophisticated defense mechanisms against herbivores to help them adapt to the environment. Understanding the defense mechanisms in plants can help us control insects in a more effective manner. In this study, we found that compared with Tianlong 2(a cultivated soybean with insect susceptibility), ED059(a wild soybean line with insect resistance)contains sharper pubescence tips, as well as lower transcript levels of wound-induced protein kinase(WIPK) and salicylic acid-induced protein kinase(SIPK), which are important mitogen-activated protein kinases involved in early defense response to herbivores. The observed lower transcript levels of WIPK and SIPK induced higher levels of jasmonic acid(JA), JA biosynthesis enzymes(AOC3) and some secondary metabolites in ED059. Functional analysis of the KTI1 gene via Agrobacterium-mediated transformation in Arabidopsis thaliana indicated that it plays an important role in herbivore defense in ED059. We further investigated the molecular response of third-instar Helicoverpa armigera(Hübner) larvae to Tianlong 2 and ED059. We found apoptotic cells only in the midguts of larvae that fed on ED059. Compared with larvae reared on the susceptible cultivar Tianlong 2, transcript levels of catalase(CAT) and glutathione S-transferase(GST) were up-regulated, whereas those of CAR, CHSB, and TRY were down-regulated in larvae that fed on the highly resistant variety ED059. We propose that these differences underlie the different herbivore defense responses of ED059 and Tianlong 2.展开更多
Here we use amplified fragment length polymorphism (AFLP) to assess genetic differentiation of Helicoverpa armigera and H. assulta. The results indicated that both species-specific fingerprints and cluster analysis ...Here we use amplified fragment length polymorphism (AFLP) to assess genetic differentiation of Helicoverpa armigera and H. assulta. The results indicated that both species-specific fingerprints and cluster analysis showed the ability of AFLP technique to discriminate the two sibling species; among a total 1963 AFLP markers amplified from nine primer combinations: 777 (39.6%) were H. armigera-specific, 602 (30.7%) were H. assulta- specific, and 584 (29.7%) were common bands. The mean number ofH. armigera-specific bands was significantly more than that of H. assulta-specific bands for nine primer combinations (P 〈 0.05); the intraspecific distance of H. armigera and H. assulta was 0.123 0 and 0.110 7 respectively, and the interspecific distance was 0.178 3. In addition, the percentage of polymorphic loci and estimated average heterozygosity were used to estimate genetic diversity of the two species. This study therefore demonstrates that AFLP analysis is a sensitive and reliable technique to study genetic differentiation and genetic relationships between species and provides sufficient molecular markers for future linkage map conslruction, location and eventual cloning of genes involved in traits differentiation.展开更多
基金supported by the National Basic Research Program of China(2012CB114104)the National Natural Science Foundation of China(30871640,31071694)+1 种基金the National High-Tech R&D Program of China(2008AA02Z307)the International Cooperation and Exchange Foundation of NSFC-RS of China(31111130203).
文摘The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera (Hübner).The cDNA contains a 444 bp open reading frame,encoding a protein with 147 amino acids,namely HarmOBP5.HarmOBP5 was expressed in Escherichia coli and the recombinant protein was purified by affinity chromatography.SDS-PAGE and Western blot analysis demonstrated that the purified protein can be used for further investigation of its binding characteristics.Competitive binding assays with 113 odorant chemicals indicated that HarmOBP5 has strong affinity to some special plant volatiles,including (E)-β-farnesene,ethyl butyrate,ethyl heptanoate,and acetic acid 2-methylbutyl ester.Based on three-dimensional (3D) model of AaegOBP1 from Aedes aegypti,a 3D model of HarmOBP5 was predicted.The model revealed that some key binding residues in HarmOBP5 may play important roles in odorant perception of H.armigera.This study provides clues for better understanding physiological functions of OBPs in H.armigera and other insects.
基金Supported by the National Natural Science Foundation of China(31201750)Hunan Provincial Natural Science Foundation of China(2016JJ4009)
文摘The dual-choices tests of behavioral test were used to study the gustatory behavioral responses to caffeine of Helicoverpa armigera larvae and H. assulta larvae. Electrophysiological responses were studied by electrophysiological tip recording. Behavioral experiments showed that caffeine was a feeding deterrent for both larvae, but it showed a stronger feeding deterring effect on the oligophagous H. assulta . The electrophysiological tip-recording results showed that both H. armigera larvae and H. assulta larvae had one caffeine-sensitive feeding deterrent neuron at the medial sensilla, and the electrophysiological pulse response of H. assulta larvae was significantly stronger than that of H. armigera larvae. Therefore, caffeine had a stronger feeding deterring effect on the oligophagous H. assulta than the polyphagous H. armigera . The difference in behavioral effect was closely related to the sensitivity of to caffeine the feeding deterrent neurons at the medial sensilla.
基金funded by the China Agriculture Research System(CAAS-04-PS08)the National Transgenic Project of China(2014ZX08004-005)the Agricultural Science and Technology Innovation Program of China
文摘Plants have evolved sophisticated defense mechanisms against herbivores to help them adapt to the environment. Understanding the defense mechanisms in plants can help us control insects in a more effective manner. In this study, we found that compared with Tianlong 2(a cultivated soybean with insect susceptibility), ED059(a wild soybean line with insect resistance)contains sharper pubescence tips, as well as lower transcript levels of wound-induced protein kinase(WIPK) and salicylic acid-induced protein kinase(SIPK), which are important mitogen-activated protein kinases involved in early defense response to herbivores. The observed lower transcript levels of WIPK and SIPK induced higher levels of jasmonic acid(JA), JA biosynthesis enzymes(AOC3) and some secondary metabolites in ED059. Functional analysis of the KTI1 gene via Agrobacterium-mediated transformation in Arabidopsis thaliana indicated that it plays an important role in herbivore defense in ED059. We further investigated the molecular response of third-instar Helicoverpa armigera(Hübner) larvae to Tianlong 2 and ED059. We found apoptotic cells only in the midguts of larvae that fed on ED059. Compared with larvae reared on the susceptible cultivar Tianlong 2, transcript levels of catalase(CAT) and glutathione S-transferase(GST) were up-regulated, whereas those of CAR, CHSB, and TRY were down-regulated in larvae that fed on the highly resistant variety ED059. We propose that these differences underlie the different herbivore defense responses of ED059 and Tianlong 2.
基金We thank Si-Ping Li for technical contributions to this study, Dr Shi-Liang Zhou (Institute of Botany, Chinese Academy of Sciences), Jian-Cheng Shen and Qing-Bo Tang for data processing, and Li Feng for help in rearing insects. We are particularly grateful to Dr De-Xing Zhang for his constructive comments that greatly improved the manuscript. Also we appreciate thoughtful discussions with Professor Li-Huang Zhu (Institute of Genetics and Developmental Biology, Chinese Academy of Sciences). This work was supported by the National Natural Science Foundation of China (Grant Nos. 30330100 and 30471148).
文摘Here we use amplified fragment length polymorphism (AFLP) to assess genetic differentiation of Helicoverpa armigera and H. assulta. The results indicated that both species-specific fingerprints and cluster analysis showed the ability of AFLP technique to discriminate the two sibling species; among a total 1963 AFLP markers amplified from nine primer combinations: 777 (39.6%) were H. armigera-specific, 602 (30.7%) were H. assulta- specific, and 584 (29.7%) were common bands. The mean number ofH. armigera-specific bands was significantly more than that of H. assulta-specific bands for nine primer combinations (P 〈 0.05); the intraspecific distance of H. armigera and H. assulta was 0.123 0 and 0.110 7 respectively, and the interspecific distance was 0.178 3. In addition, the percentage of polymorphic loci and estimated average heterozygosity were used to estimate genetic diversity of the two species. This study therefore demonstrates that AFLP analysis is a sensitive and reliable technique to study genetic differentiation and genetic relationships between species and provides sufficient molecular markers for future linkage map conslruction, location and eventual cloning of genes involved in traits differentiation.