Conogethes punctiferalis is a crop and fruit pest that has caused serious economic losses to agricultural production.This pest relies heavily on its sex pheromone to ensure sexual encounters and subsequent mating succ...Conogethes punctiferalis is a crop and fruit pest that has caused serious economic losses to agricultural production.This pest relies heavily on its sex pheromone to ensure sexual encounters and subsequent mating success.However,the molecular mechanism underlying sex pheromone biosynthesis in this species remains elusive.The present study investigated the detailed mechanism underlying PBAN-regulated sex pheromone biosynthesis in C.punctiferalis by transcriptome sequencing of the C.punctiferalis pheromone glands(PGs)and subsequent functional identification of the target genes.The results showed that female mating started from the first scotophase,and peaked at the second to fifth scotophases in accordance with the release of sex pheromones.PBAN regulated sex pheromone biosynthesis by employing Ca^(2+)and cAMP as secondary messengers,as demonstrated by RNA interference(RNAi),pharmacological inhibitors,and behavioral assays.Further investigation revealed that calcineurin(CaN)and acetyl-CoA carboxylase(ACC)were activated by PBAN/Ca^(2+)signaling,and the RNAimediated knockdown of CaN and ACC transcripts significantly reduced sex pheromone production,ultimately leading to a significantly reduced ability of females to attract males.Importantly,hexokinase(HK)was found to regulate sex pheromone biosynthesis in response to the PBAN/cAMP/PKA signaling pathway,as demonstrated by RNAi,enzyme activity,and pharmacological inhibitor assays.Furthermore,Far2 and Desaturase1 were found to participate in PBAN-regulated sex pheromone biosynthesis.Altogether,our findings revealed that PBAN regulates sex pheromone biosynthesis through the PBANR/Ca^(2+)/CaN/ACC and PBANR/cAMP/PKA/HK pathways in C.punctiferalis,which enriches our comprehension of the details of sex pheromone biosynthesis in moths.展开更多
Helicoverpa zea is a major target pest of pyramided transgenic crops expressing Cry1,Cry2 and/or Vip3Aa proteins from Bacillus thuringiensis(Bt)in the United States.Laboratory-selected Cry1Ac/Cry2Ab cross resistance a...Helicoverpa zea is a major target pest of pyramided transgenic crops expressing Cry1,Cry2 and/or Vip3Aa proteins from Bacillus thuringiensis(Bt)in the United States.Laboratory-selected Cry1Ac/Cry2Ab cross resistance and fieldevolved practical dual resistance of H.zea to these two toxins have been widely reported.Whether the widespread Cry1Ac/Cy2Ab dual resistance of H.zea has resulted from the selection of one shared or two independent resistance mechanisms by pyramided Bt crops remains unclear.Cadherin is a well-confirmed receptor of Cry1Ac and a suggested receptor of Cry2Ab in at least three Lepidopteran species.To test whether cadherin may serve as one shared mechanism for the cross and dual resistance of H.zea to Cry1Ac and Cry2Ab,we cloned H.zea cadherin(HzCadherin)cDNA and studied its functional roles in the mode of action of Cry1Ac and Cry2Ab by gain-and lossof-function analyses.Heterologous expression of HzCadherin in H.zea midgut,H.zea fat body and Sf9 cells made all three of these cell lines more susceptible to activated Cry1Ac but not activated Cry2Ab,whereas silencing HzCadherin of H.zea midgut and fat body cells significantly reduced the susceptibility to Cry1Ac but not Cry2Ab.Likewise,suppressing HzCadherin with siRNA made H.zea larvae resistant to Cry1Ac.These results clearly demonstrate that HzCadherin is not a receptor for Cry2Ab,and thus it is unlikely to serve as one shared mechanism for the cross and dual resistance of H.zea to Cry1Ac and Cry2Ab.展开更多
While CrylAc has been known to bind with larval midgut proteins cad- herin, APN （amino peptidase N）, ALP （alkaline phosphatase） and ABCC2 （adenosine triphosphate-binding cassette transporter subfamily C2）, littl...While CrylAc has been known to bind with larval midgut proteins cad- herin, APN （amino peptidase N）, ALP （alkaline phosphatase） and ABCC2 （adenosine triphosphate-binding cassette transporter subfamily C2）, little is known about the recep- tors of Cry2Ab. To provide a clue to the receptors of Cry2Ab, we tested the baseline cytotoxicity of activated Cry 1Ac and Cry2Ab against the midgut and fat body cell lines of Helicoverpa zea and the ovary cell line ofSpodopterafrugiperda （SFg）. As expected, the descending order of cytotoxicity of CrylAc against the three cell lines in terms of 50% lethal concetration （LC50） was midgut （31.0μg/mL） 〉 fat body （59.0μg/mL） and SF9 cell （99.6μg/mL）. By contrast, the fat body cell line （LC50 = 7.55μg/mL） was about twice more susceptible to Cry2Ab than the midgut cell line （16.0/xg/mL）, the susceptibility of which was not significantly greater than that of SF9 cells （27.0μg/mL）. Further, ligand blot showed the binding differences between CrylAc and Cry2Ab in the three cell lines. These results indicated that the receptors of Cry2Ab were enriched in fat body cells and thus largely different from the receptors of CrylAc, which were enriched in midgut cells.展开更多
基金supported by the National Natural Science Foundation of China(31970472,32272547)the National Science Fund of Henan Province for Distinguished Young Scholars,China(202300410191)+3 种基金the Basic Research Project of the Key Scientific Research Projects of Universities in Henan Province,China(21zx013)the Henan Agricultural Research System,China(HARS-2209-G3)the Henan Special Support for High-Level Talents Central Plains Science and Technology Innovation Leading Talents,China(224200510018)the earmarked fund for China Agricultural Research System(CARS-27)。
文摘Conogethes punctiferalis is a crop and fruit pest that has caused serious economic losses to agricultural production.This pest relies heavily on its sex pheromone to ensure sexual encounters and subsequent mating success.However,the molecular mechanism underlying sex pheromone biosynthesis in this species remains elusive.The present study investigated the detailed mechanism underlying PBAN-regulated sex pheromone biosynthesis in C.punctiferalis by transcriptome sequencing of the C.punctiferalis pheromone glands(PGs)and subsequent functional identification of the target genes.The results showed that female mating started from the first scotophase,and peaked at the second to fifth scotophases in accordance with the release of sex pheromones.PBAN regulated sex pheromone biosynthesis by employing Ca^(2+)and cAMP as secondary messengers,as demonstrated by RNA interference(RNAi),pharmacological inhibitors,and behavioral assays.Further investigation revealed that calcineurin(CaN)and acetyl-CoA carboxylase(ACC)were activated by PBAN/Ca^(2+)signaling,and the RNAimediated knockdown of CaN and ACC transcripts significantly reduced sex pheromone production,ultimately leading to a significantly reduced ability of females to attract males.Importantly,hexokinase(HK)was found to regulate sex pheromone biosynthesis in response to the PBAN/cAMP/PKA signaling pathway,as demonstrated by RNAi,enzyme activity,and pharmacological inhibitor assays.Furthermore,Far2 and Desaturase1 were found to participate in PBAN-regulated sex pheromone biosynthesis.Altogether,our findings revealed that PBAN regulates sex pheromone biosynthesis through the PBANR/Ca^(2+)/CaN/ACC and PBANR/cAMP/PKA/HK pathways in C.punctiferalis,which enriches our comprehension of the details of sex pheromone biosynthesis in moths.
基金funded by the USDA National Institute of Food and Agriculture (Hatch Grant ARZT-1360890-H31-164 and multi-state grant ARZ-T1370680-R31-172 (NC246))the National Natural Science Foundation of China (NSFC)–Henan Joint Major Grant (U2004206)+2 种基金the State Key Laboratory of Cotton Biology Open Fund, Zhengzhou University, China (CB2020A06)the Henan Agriculture Research System, China (HARS22-09-G3)the earmarked fund for China Agriculture Research System (CARS-27)
文摘Helicoverpa zea is a major target pest of pyramided transgenic crops expressing Cry1,Cry2 and/or Vip3Aa proteins from Bacillus thuringiensis(Bt)in the United States.Laboratory-selected Cry1Ac/Cry2Ab cross resistance and fieldevolved practical dual resistance of H.zea to these two toxins have been widely reported.Whether the widespread Cry1Ac/Cy2Ab dual resistance of H.zea has resulted from the selection of one shared or two independent resistance mechanisms by pyramided Bt crops remains unclear.Cadherin is a well-confirmed receptor of Cry1Ac and a suggested receptor of Cry2Ab in at least three Lepidopteran species.To test whether cadherin may serve as one shared mechanism for the cross and dual resistance of H.zea to Cry1Ac and Cry2Ab,we cloned H.zea cadherin(HzCadherin)cDNA and studied its functional roles in the mode of action of Cry1Ac and Cry2Ab by gain-and lossof-function analyses.Heterologous expression of HzCadherin in H.zea midgut,H.zea fat body and Sf9 cells made all three of these cell lines more susceptible to activated Cry1Ac but not activated Cry2Ab,whereas silencing HzCadherin of H.zea midgut and fat body cells significantly reduced the susceptibility to Cry1Ac but not Cry2Ab.Likewise,suppressing HzCadherin with siRNA made H.zea larvae resistant to Cry1Ac.These results clearly demonstrate that HzCadherin is not a receptor for Cry2Ab,and thus it is unlikely to serve as one shared mechanism for the cross and dual resistance of H.zea to Cry1Ac and Cry2Ab.
文摘While CrylAc has been known to bind with larval midgut proteins cad- herin, APN （amino peptidase N）, ALP （alkaline phosphatase） and ABCC2 （adenosine triphosphate-binding cassette transporter subfamily C2）, little is known about the recep- tors of Cry2Ab. To provide a clue to the receptors of Cry2Ab, we tested the baseline cytotoxicity of activated Cry 1Ac and Cry2Ab against the midgut and fat body cell lines of Helicoverpa zea and the ovary cell line ofSpodopterafrugiperda （SFg）. As expected, the descending order of cytotoxicity of CrylAc against the three cell lines in terms of 50% lethal concetration （LC50） was midgut （31.0μg/mL） 〉 fat body （59.0μg/mL） and SF9 cell （99.6μg/mL）. By contrast, the fat body cell line （LC50 = 7.55μg/mL） was about twice more susceptible to Cry2Ab than the midgut cell line （16.0/xg/mL）, the susceptibility of which was not significantly greater than that of SF9 cells （27.0μg/mL）. Further, ligand blot showed the binding differences between CrylAc and Cry2Ab in the three cell lines. These results indicated that the receptors of Cry2Ab were enriched in fat body cells and thus largely different from the receptors of CrylAc, which were enriched in midgut cells.
