INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY
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2015
·
IF 3.45
Lulu Dai,Mingyuan Ma,Chunyan Wang,Qi Shi,Ranran Zhang,Hui Chen
Bark beetles oxidize the defensive allelochemicals from their host trees to both detoxify and convert these materials into components of their pheromone system. The ability of this insect to adapt to its chemical environment might be explained by the action of major detoxification enzymes such as cytochrome P450s (or CYPs). Sixty-four sequences coding for P450s were identified, and most of the transcripts were found to be expressed in the larvae, pupae and adults of Dendroctonus armandi . To gain information on how these genes help D. armandi overcome the host defense, differential transcript levels of the CYP genes were observed between sexes and within the sexes. Significant differences were observed among developmental stages, in feeding on the phloem of Pinus armandi and in exposure to stimuli ((±)-α-pinene, (S)-(−)-α-pinene, (S)-(−)-β-pinene, (+)-3-carene, (±)-limonene and turpentine oil) for 8 h. We investigated the effect of sex and generations on the survivorship of individual D. armandi that were exposed to host volatiles at concentrations comparable to constitutive and induced levels of defense using fumigant exposure to understand the ability of the beetles to tolerate host defensive chemicals. The differential transcript accumulation patterns of CYP genes of these bark beetle provided insight into the ecological interactions of D. armandi with its host pine.
研究领域:
昆虫学
·
分子生物学
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DOI
高影响因子
PEST MANAGEMENT SCIENCE
·
2018
·Vol. 75
·期 4
·986-997
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IF 3.249
Lulu Dai,Haiming Gao,Jiaqi Ye,Danyang Fu,Yaya Sun,Hui Chen
BACKGROUND Bark beetles rely on detoxifying enzymes to resist the defensive terpenoids of their host trees. Research on carboxylesterases (CarEs) has focused on their multiple functions in the metabolic detoxification of pesticides and plant allelochemicals, drug resistance, and juvenile hormone and pheromone degradation. RESULT We identified eight new CarE genes in the Chinese white pine beetle ( Dendroctonus armandi ) and carried out bioinformatics analysis on the deduced full-length amino acid sequences. Differential transcript levels of CarE genes were observed between sexes; within these levels, significant differences were found among the different development stages, and between insects fed on the phloem of Pinus armandi and exposed to five stimuli [(−)-α-pinene, (−)-β-pinene, (+)-3-carene, limonene and turpentine] at 8 and 24 h. CONCLUSION Transcription levels of CarE genes suggest some relationship with the detoxification of terpenoids released by host trees. The functions of bark beetle esterase are mainly in hydrolyzing the host chemical defense and degrading odorant molecules during host selection and colonization. © 2018 Society of Chemical Industry
研究领域:
昆虫学
·
分子生物学
·
生物化学
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产品关联
DOI
PubMed
高影响因子
Insects
·
2021
·Vol. 12
·期 10
·926
·
IF 2.769
Lulu Dai,Haiming Gao,Hui Chen
Simple SummaryThe bark beetle is the most well-known pest in coniferous trees worldwide. These insects only leave the host pine bark when they disperse to locate a new host. Determining howDendroctonus armandiovercome the trees’ terpene-based defense systems has been the key problem in the study of bark beetles. Therefore, the aim of this study was to discover the molecular mechanism of insect detoxification enzymes’ ability to confer resistance to terpenes. For this purpose, the genes of cytochrome P450s, glutathione S-transferases, and carboxylesterases were studied in beetles given diets containing terpenes. The results suggest that beetles express different genes in response to terpenoids, and the responses of multiple detoxifying enzymes indicate these insects’ adaption to their chemical environment.AbstractBark beetles overcome the toxic terpenoids produced by pine trees by both detoxifying and converting them into a pheromone system. Detoxification enzymes such as cytochrome P450s, glutathione S-transferases, and carboxylesterases are involved in the ability ofDendroctonus armandito adapt to its chemical environment. Ten genes from these three major classes of detoxification enzymes were selected to study how these enzymes helpD. armandito respond to the host defenses. The expression profile of these detoxification enzyme genes was observed in adult beetles after feeding on different types of diet. Significant differences were observed between two types of seminatural diet containing the phloem of pines, and a purely artificial diet containing five monoterpenes ((−)-α-pinene, (−)-β-pinene, (+)-3-carene, (±)-limonene, and turpentine oil) also caused differential transcript levels in the detoxification enzyme genes. The results suggest that monoterpenes enter the beetles through different routes (i.e., respiratory and digestive systems) and cause the expression of different genes in response, which might be involved in pheromone metabolism. In addition, the xenobiotic metabolism in bark beetles should be considered as a system comprising multiple detoxifying enzymes.Keywords:artificial feeding;chemical defense;Chinese white pine beetle;cytochrome P450;real-time qPCR
研究领域:
昆虫学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PEST MANAGEMENT SCIENCE
·
2015
·Vol. 72
·期 4
·816-827
·
IF 2.694
Lulu Dai,Junning Ma,Mingyuan Ma,Haoqiang Zhang,Qi Shi,Ranran Zhang,Hui Chen
BACKGROUND Bark beetles rely on their detoxifying enzymes to resist the defensive terpenoids of host trees. Glutathione S -transferases (GSTs) conjugate xenobiotic compounds with a glutathione moiety (GSH) and often work in tandem with cytochromes P450 or other enzymes that aid in the detoxification, sequestration or excretion of toxic compounds. RESULT We identified nine new GST genes in the Chinese white pine beetle ( Dendroctonus armandi ) and carried out a bioinformatics analysis on the deduced full-length amino acid sequences. These genes belong to four different classes (epsilon, sigma, omega and theta). Differential transcript levels of each class of GST genes were observed between sexes, and, within these levels, significant differences were found among the different adult substages that were fed phloem of Pinus armandi and exposed to six stimuli [(±)- α -pinene, (−)- α -pinene, (−)- β -pinene, (+)-3-carene, (±)-limonene and turpentine] at 8 and 24 h. CONCLUSION The increased transcription levels of GST genes suggested that they have some relationship with the detoxification of terpenoids that are released by host trees. The mediating oxidative stress that is caused by monoterpene might be the main role of the bark beetle GSTs. © 2015 Society of Chemical Industry
研究领域:
昆虫学
·
分子生物学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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