Aphids are major insect pests in agriculture and forestry worldwide.Following attacks by natural enemies,many aphids release an alarm pheromone to protect their population.In most aphids,the main component of the aphi...Aphids are major insect pests in agriculture and forestry worldwide.Following attacks by natural enemies,many aphids release an alarm pheromone to protect their population.In most aphids,the main component of the aphid alarm pheromone(AAP)is the sesquiterpene hydrocarbon(E)-β-farnesene(EβF).However,the mechanisms behind its biosynthesis and regulation remain poorly understood.In this study,we used the bird cherry–oat aphid Rhopalosiphum padi,which is an important wheat aphid,to investigate the regulatory mechanisms of EβF biosynthesis.Our results showed that EβF biosynthesis occurs during the mature embryo period and the molting period of the 1st-and 2nd-instar nymphs.Triglycerides provide the prerequisite material for EβF production and release.Based on transcriptome sequencing,RNAi analysis,hormone treatments,and quantitative measurements,we found that the biosynthesis of EβF utilizes acetyl coenzyme A produced from fatty acid degradation,which can be suppressed by juvenile hormone but it is promoted by 20-hydroxyecdysone through the modulation of fatty acid metabolism.This is the first systemic study on the modulation of EβF production in aphids.The results of our study provide insights into the molecular regulatory mechanisms of AAP biosynthesis,as well as valuable information for designing potential aphid control strategies.展开更多
Aphids are major agricultural pests that cause significant yield losses of crop plants each year. Excessive dependence on insec- ticides for long-term aphid control is undesirable because of the development of insecti...Aphids are major agricultural pests that cause significant yield losses of crop plants each year. Excessive dependence on insec- ticides for long-term aphid control is undesirable because of the development of insecticide resistance, the potential negative effects on non-target organisms and environmental pollution. Transgenic crops engineered for resistance to aphids via a non-toxic mode of action could be an efficient alternative strategy. （E）-β-Farnesene （EβF） synthases catalyze the formation of EβF, which for many pest aphids is the main component of the alarm pheromone involved in the chemical communication within these species. EβF can also be synthesized by certain plants but is then normally contaminated with inhibitory compounds. Engineering of crop plants capable ofsynthesizing and emitting EβF could cause repulsion of aphids and also the attraction of natural enemies that use EβF as a foraging cue, thus minimizing aphid infestation. In this review, the effects of aphids on host plants, plants＇ defenses against aphid herbivory and the recruitment of natural enemies for aphid control in an agricultural setting are briefly introduced. Furthermore, the plant-derived EβF synthase genes cloned to date along with their potential roles in generating novel aphid resistance via genetically modified approaches are discussed.展开更多
Terpenoids have tremendous biological activities and are widely employed in food,healthcare and pharmaceutical industries.Using synthetic biology to product terpenoids from microbial cell factories presents a promisin...Terpenoids have tremendous biological activities and are widely employed in food,healthcare and pharmaceutical industries.Using synthetic biology to product terpenoids from microbial cell factories presents a promising alternative route compared to conventional methods such as chemical synthesis or phytoextraction.The red yeast Rhodotorula mucilaginosa has been widely studied due to its natural production capacity of carotenoid and lipids,indicating a strong endogenous isoprene pathway with readily available metabolic intermediates.This study constructed several engineered strains of R.mucilaginosa with the aim of producing different terpenoids.Monoterpeneα-terpineol was produced by expressing theα-terpineol synthase from Vitis vinifera.The titer ofα-terpineol was further enhanced to 0.39 mg/L by overexpressing the endogenous rate-limiting gene of the MVA pathway.Overexpression ofα-farnesene synthase from Malus domestica,in combination with MVA pathway rate-limiting gene resulted in significant increase inα-farnesene production,reaching a titer of 822 mg/L.The carotenoid degradation productβ-ionone was produced at a titer of 0.87 mg/L by expressing theβ-ionone synthase from Petunia hybrida.This study demonstrates the potential of R.mucilaginosa as a platform host for the direct biosynthesis of various terpenoids and provides insights for further development of such platforms.展开更多
Ants use species-specific trail pheromones to coordinate their sophisticated foraging behavior.During the past decades,many trail pheromone components with various structures have been identified in ants,including the...Ants use species-specific trail pheromones to coordinate their sophisticated foraging behavior.During the past decades,many trail pheromone components with various structures have been identified in ants,including the red imported fire ant,Solenopsis invicta,a notorious invasive species worldwide.Four compounds,Z,E-(ZEF)and E,E-α-farnesene(EEF),Z,E-(ZEHF)and E,E-α-homofarnesene(EEHF),have been reported as components of S.invicta trail pheromone.However,another study reported an analog ofα-farnesene,Z,Z,Z-allofarnesene,as a key trail pheromone component.These contrasting results caused some uncertainty about the trail pheromone composition in S.invicta.In this study,we synthesized ZEF and EEF,ZEHF and EEHF,and reanalyzed the chemicals in the Dufour gland extract and in the trail pheromone fraction of S.invicta worker body extract.The reported isomers of farnesene and homofarnesene were detected and showed trail-following activity,with ZEF as the major compound,while no allofarnesene was found,neither in the Dufour gland extract nor in the whole-body extract.Our results confirm ZEF and EEF,ZEHF and EEHF as trail pheromone components of S.invicta.展开更多
基金supported by the National Natural Science Foundation of China(31972267 and 3227253)the Chinese Universities Scientific Fund(2023TC109)。
文摘Aphids are major insect pests in agriculture and forestry worldwide.Following attacks by natural enemies,many aphids release an alarm pheromone to protect their population.In most aphids,the main component of the aphid alarm pheromone(AAP)is the sesquiterpene hydrocarbon(E)-β-farnesene(EβF).However,the mechanisms behind its biosynthesis and regulation remain poorly understood.In this study,we used the bird cherry–oat aphid Rhopalosiphum padi,which is an important wheat aphid,to investigate the regulatory mechanisms of EβF biosynthesis.Our results showed that EβF biosynthesis occurs during the mature embryo period and the molting period of the 1st-and 2nd-instar nymphs.Triglycerides provide the prerequisite material for EβF production and release.Based on transcriptome sequencing,RNAi analysis,hormone treatments,and quantitative measurements,we found that the biosynthesis of EβF utilizes acetyl coenzyme A produced from fatty acid degradation,which can be suppressed by juvenile hormone but it is promoted by 20-hydroxyecdysone through the modulation of fatty acid metabolism.This is the first systemic study on the modulation of EβF production in aphids.The results of our study provide insights into the molecular regulatory mechanisms of AAP biosynthesis,as well as valuable information for designing potential aphid control strategies.
基金Some work mentioned in this review is partly funded by the Research Initiative on Development of Disease and Insect Resistance Transgenic Wheat Plants supported by the Chinese Ministry of Agriculture (2008ZX08002-001)Natural Science Foundation of China (31171618)+1 种基金the EU FP7 OPTICHINA Project (266045)Rothamsted Research receives grant-aided support from the Biotechnology and Biological Sciences Research Council (BBSRC) of the UK
文摘Aphids are major agricultural pests that cause significant yield losses of crop plants each year. Excessive dependence on insec- ticides for long-term aphid control is undesirable because of the development of insecticide resistance, the potential negative effects on non-target organisms and environmental pollution. Transgenic crops engineered for resistance to aphids via a non-toxic mode of action could be an efficient alternative strategy. （E）-β-Farnesene （EβF） synthases catalyze the formation of EβF, which for many pest aphids is the main component of the alarm pheromone involved in the chemical communication within these species. EβF can also be synthesized by certain plants but is then normally contaminated with inhibitory compounds. Engineering of crop plants capable ofsynthesizing and emitting EβF could cause repulsion of aphids and also the attraction of natural enemies that use EβF as a foraging cue, thus minimizing aphid infestation. In this review, the effects of aphids on host plants, plants＇ defenses against aphid herbivory and the recruitment of natural enemies for aphid control in an agricultural setting are briefly introduced. Furthermore, the plant-derived EβF synthase genes cloned to date along with their potential roles in generating novel aphid resistance via genetically modified approaches are discussed.
基金National Key Research and Development Program of China(2021YFA0910600)National Natural Science Foundation of China(22308350,22238010)+1 种基金Liaoning Revitalization Talents Program(XLYC2002089)Science and Technology Bureau of Dalian City(2021RT04).
文摘Terpenoids have tremendous biological activities and are widely employed in food,healthcare and pharmaceutical industries.Using synthetic biology to product terpenoids from microbial cell factories presents a promising alternative route compared to conventional methods such as chemical synthesis or phytoextraction.The red yeast Rhodotorula mucilaginosa has been widely studied due to its natural production capacity of carotenoid and lipids,indicating a strong endogenous isoprene pathway with readily available metabolic intermediates.This study constructed several engineered strains of R.mucilaginosa with the aim of producing different terpenoids.Monoterpeneα-terpineol was produced by expressing theα-terpineol synthase from Vitis vinifera.The titer ofα-terpineol was further enhanced to 0.39 mg/L by overexpressing the endogenous rate-limiting gene of the MVA pathway.Overexpression ofα-farnesene synthase from Malus domestica,in combination with MVA pathway rate-limiting gene resulted in significant increase inα-farnesene production,reaching a titer of 822 mg/L.The carotenoid degradation productβ-ionone was produced at a titer of 0.87 mg/L by expressing theβ-ionone synthase from Petunia hybrida.This study demonstrates the potential of R.mucilaginosa as a platform host for the direct biosynthesis of various terpenoids and provides insights for further development of such platforms.
基金supported by National Key R&D Program of China(Grant No.2021YFD1000500)National Natural Science Foundation of China(Grant Nos.31702050 and 32070488)the State Key Laboratory of Integrated Management of Pest Insects and Rodents(Grant No.ChineseIPM1410).
文摘Ants use species-specific trail pheromones to coordinate their sophisticated foraging behavior.During the past decades,many trail pheromone components with various structures have been identified in ants,including the red imported fire ant,Solenopsis invicta,a notorious invasive species worldwide.Four compounds,Z,E-(ZEF)and E,E-α-farnesene(EEF),Z,E-(ZEHF)and E,E-α-homofarnesene(EEHF),have been reported as components of S.invicta trail pheromone.However,another study reported an analog ofα-farnesene,Z,Z,Z-allofarnesene,as a key trail pheromone component.These contrasting results caused some uncertainty about the trail pheromone composition in S.invicta.In this study,we synthesized ZEF and EEF,ZEHF and EEHF,and reanalyzed the chemicals in the Dufour gland extract and in the trail pheromone fraction of S.invicta worker body extract.The reported isomers of farnesene and homofarnesene were detected and showed trail-following activity,with ZEF as the major compound,while no allofarnesene was found,neither in the Dufour gland extract nor in the whole-body extract.Our results confirm ZEF and EEF,ZEHF and EEHF as trail pheromone components of S.invicta.
