INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY
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2019
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IF 3.618
Xiao-Jin Pei,Nan Chen,Yu Bai,Jian-Wen Qiao,Sheng Li,Yong-Liang Fan,Tong-Xian Liu
Insect cuticular hydrocarbons (CHCs), the evolutionary products of aquatic hexapod ancestors expanding to terrestrial environment, are deposited on the surface of insect integument and originally functioned primarily as waterproofing agents. CHCs are derived from the conserved fatty acid synthesis pathway in insects. However, the pivotal fatty acid synthase (FAS) involved in hydrocarbon (HC) biosynthesis remains unknown in many insect orders including the primitive Blattodea . Here, we investigated functional FAS genes that modulate cuticular lipid biogenesis in the German cockroach , Blattella germanica (L.). Based on our full-length transcriptomic data and the available genomic data, seven FAS genes ( BgFas1–7 ) were identified from B. germanica . Tissue-specific expression analysis revealed that BgFas1 , BgFas3 , BgFas4 and BgFas7 were highly expressed in the integument, whereas BgFas2 was dominantly expressed in the fat body. BgFas5 /6 mRNA was almost negligible in the tested tissues. Systemic RNAi screen was performed against BgFas1–7 , we found that only RNAi knockdown of BgFas1 caused a dramatic reduction of methyl-branched HCs (mbHCs) and a slight decrease of straight-chain HCs (scHCs) for both internal and external HCs. Significant reduction of cuticular free fatty acids (cFFAs) was also detected within BgFas1 -repressed cockroaches, while repression of CYP4G19 resulted in dramatic increase of cFFAs. Moreover, we found that BgFas1 mRNA levels were correlated with insect molting cycles, and could be induced by long-term mild dryness treatment. Furthermore, desiccation assay revealed that BgFas1 suppression accelerated water loss and led to early death of cockroaches under desiccation. Our results indicate that BgFas1 is necessary for both HC and cFFA biosynthesis in B. germanica . In addition, our study also confirms that cuticular lipids, particularly mbCHCs, are critical for desiccation resistance in B. germanica .
研究领域:
昆虫学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Insect Science
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2023
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IF 4
Xiaojin Pei,Tiantian Bai,Yuan Luo,Zhanfeng Zhang,Sheng Li,Yongliang Fan,Tong-Xian Liu
Lipid and sugar homeostasis is critical for insect development and survival. In this study, we characterized an acetyl coenzyme A carboxylase gene in Blattella germanica ( BgACC ) that is involved in both lipogenesis and sugar homeostasis. We found that BgACC was dominantly expressed in the fat body and integument, and was significantly upregulated after molting. Knockdown of BgACC in 5th-instar nymphs did not affect their normal molting to the next nymphal stage, but it caused a lethal phenotype during adult emergence. BgACC -RNA interference (RNAi) significantly downregulated total free fatty acid (FFA) and triacylglycerol (TAG) levels, and also caused a significant decrease of cuticular hydrocarbons (CHCs). Repression of BgACC in adult females affected the development of oocytes and resulted in sterile females, but BgACC -RNAi did not affect the reproductive ability of males. Interestingly, knockdown of BgACC also changed the expression of insulin-like peptide genes ( BgILP s), which mimicked a physiological state of high sugar uptake. In addition, BgACC was upregulated when B. germanica were fed on a high sucrose diet, and repression of BgACC upregulated the expression of the glycogen synthase gene ( BgGlyS ). Moreover, BgACC -RNAi increased the circulating sugar levels and glycogen storage, and a longevity assay suggested that BgACC was important for the survival of B. germanica under conditions of high sucrose uptake. Our results confirm that BgACC is involved in multiple lipid biogenesis and sugar homeostasis processes, which further modulates insect reproduction and sugar tolerance. This study benefits our understanding of the crosstalk between lipid and sugar metabolism.
研究领域:
昆虫学
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分子生物学
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生理学
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生物化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ASIA-PACIFIC ENTOMOLOGY
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2021
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IF 1.303
Yalei Li,Xiaoying Lan,Kun Qian,Jinlin Liu,Zongqing Wang
Bait formulations are widely used for controlling the German cockroach, but cockroaches increasingly come into aversion and resistance to bait formulations. To optimize baits and delay insecticides resistance to Blattella germanica , five insecticides with different mechanisms of action were selected to test the stomach toxicity of B. germanica , and twelve nutrient-rich foods were selected to test the palatability of B. germanica in the research. The results revealed that flufiprole and dinotefuran had a significant effect on the decrease of B. germanica population, whereas hydramethylnon, permethrin did not work well in 72 h stomach toxicity and acrinathrin had a short potency in pesticide formulation because of its semi-volatile physical properties. Furthermore, B. germanica prefers the poison bait to rat feed. This research represents the bait consisting of peanut powder and maltose (9:1) has the best palatability to B. germanica , and flufiprole and dinotefuran have a lot of potential in baits development and application.
研究领域:
昆虫学
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害虫控制
✓ 已验证
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2023
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IF 6.1
Yun-Feng Ma,Lang-Lang Gong,Meng-Qi Zhang,Xuan-Zheng Liu,Huan Guo,J. Joe Hull,Gui-Jun Long,Hong Wang,Youssef Dewer,Fan Zhang,Ming He,Peng He
Insects have evolved an extremely sensitive olfactory system that is essential for a series of physiological and behavioral activities. Some carboxylesterases (CCEs) comprise a major subfamily of odorant-degrading enzymes (ODEs) playing a crucial role in odorant signal inactivation to maintain the odorant receptor sensitivity. In this study, 93 CCEs were annotated in the genome of the German cockroach Blattella germanica, a serious urban pest. Phylogenetic and digital tissue expression pattern analyses identified two antenna-enriched CCEs, BgerCCE021e3 and BgerCCE021d1, as candidate ODEs. RNA interference (RNAi)-mediated knockdown of BgerCCE021e3 and BgerCCE021d1 resulted in partial anosmia with experimental insects exhibiting reduced attraction to ester volatile resources and slower olfactory responses than controls. Furthermore, enzymatic conversion of geranyl acetate by crude male antennal extracts from BgerCCE021e3 and BgerCCE021d1 RNAi insects was also significantly reduced. Our results provide evidence for CCE function in German cockroach olfaction and provide a basis for further exploring behavioral inhibitors that target olfactory-related CCEs.
研究领域:
昆虫学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Arthropod-Borne Diseases
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2012
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IF 0
Wei Xiang Zhu,Kun Zhao,Sha Sha Chu,Zhi Long Liu
Background: The efficacy of essential oil of Chenopodium ambrosioides flowering aerial parts and its three main active ingredients was evaluated against Blattella germanica male adults. Methods: Composition of essential oil was determined by GC-MS. Topical application bioassay was used to evaluate contact toxicity of essential oil and three main components. Fumigant toxicity of essential oil and its main components was measured using a sealed space method. Results: Twenty-two components were identified in the essential oil and the main components were ( Z )-ascaridole (29.7%), isoascaridole (13.0%), ρ-cymene (12.7%) and piperitone (5.0%). The essential oil and ( Z )-ascaridole, isoascaridole and ρ-cymene possessed fumigant toxicity against male German cockroaches with LC 50 values of 4.13, 0.55, 2.07 and 6.92 mg/L air, respectively. Topical application bioassay showed that all the three compounds were toxic to male German cockroaches and ( Z )-ascaridole was the strongest with a LD 50 value of 22.02 μg/adult while the crude oil with a LD 50 value of 67.46 μg/adult. Conclusion: The essential oil from Chinese C. ambrosioides and its three main active ingredients may be explored as natural potential insecticides in the control of cockroaches.
研究领域:
昆虫学
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植物化学
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天然产物研究
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DOI
PubMed
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2024
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IF 5.7
Jian Zhu,Yunyan Lai,Yinhua Wu,Jiali Wang,Jiaqi Wei,Hanhong Xu
We screened the contact activity of 32 commercial essential oils (EOs) and their synergistic effect with β-cypermethrin against Blattella germanica. Results showed that the most effective EOs against B. germanica were from Illicium verum, Syzygium aromaticum, and Cinnamomum camphora, with LD50 values of less than 500 μg/insect. The most potent synergistic effects of β-cypermethrin on B. germanica were from Dysphania ambrosioides and Mentha canadensis. Both oils have a co-toxic factor of 133.33. The results of the major compound testing of the EOs showed that trans-anisaldehyde and thymol have the best insecticidal activity against B. germanica, with LD50 values of 141.30 and 138.61 μg/insect, respectively. The compounds with the best synergistic effect on β-cypermethrin were γ-terpinene and linalool at a concentration of 0.5%. The co-toxic factors for γ-terpinene and linalool were 150 and 133.33, respectively, which were similar to the synergistic effect observed with 2% piperonyl butoxide.
研究领域:
昆虫学
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植物化学
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害虫管理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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