Insect growth regulators play an important role in integrated pest management strategies.The FGLa–allatostatins（ASTs）are a family of neuropeptides that can inhibit juvenile hormone（JH）biosynthesis by the corpora ...Insect growth regulators play an important role in integrated pest management strategies.The FGLa–allatostatins（ASTs）are a family of neuropeptides that can inhibit juvenile hormone（JH）biosynthesis by the corpora allata（CA）of Diploptera punctata in vitro,are regarded as insect growth regulator candidates.In the search for new potential mimics and to explore the effect of linker length on inhibiting JH biosynthesis,a series of AST analogs were synthesized by modifying the linker of K24,which was found to have a significant effect on JH biosynthesis in vitro in our previous study.Functional evaluation demonstrated that all the target compounds can activate the Dippu-Ast R,albeit with different potencies.Analog L6 with the longest linker（n=5）,exhibited not only a promising effect on inhibition of JH biosynthesis both in vitro and in vivo,but also good activity in inhibiting basal oocyte growth.Structure–activity relationships（SAR）studies showed that longer linkers provided greater contribution to activity.展开更多
Vitellogenin receptor(VgR)is crucial for vitellogenin(Vg)uptake by oocytes.VgR is less known in Arachnida,especially in spiders.Different from only one VgR in an arthropod species,two VgRs,VgR-1 and VgR-2,were found i...Vitellogenin receptor(VgR)is crucial for vitellogenin(Vg)uptake by oocytes.VgR is less known in Arachnida,especially in spiders.Different from only one VgR in an arthropod species,two VgRs,VgR-1 and VgR-2,were found in the pond wolf spider,Pardosa pseudoannulata.Both VgRs had the typical domains of the low-density lipoprotein receptor family except for the absence of the ligand-binding domain 1 in VgR-2.Spatiotemporal expression profiles showed that two VgR genes were consistently highly expressed in females and their ovaries,but VgR-1 was 48-fold that of VgR-2 in ovaries.The transcriptional level of VgR-1 was significantly downregulated by RNAi,but it did not work for VgR-2 although several trials were performed.Vg-1 and Vg-2 might be the ligands of VgR-1 because their expressions were also decreased in the dsVgR-1-treated females.Silencing VgR-1 prolonged the pre-oviposition period by 56 h.The expression of VgRs and Vgs were upregulated by juvenile hormones(JHs),which suggested that JHs were the essential factors to vitellogenesis in the spider.The present study revealed the importance of VgR-1 in the spider oviposition,which will improve the understanding on VgR physiological functions in spiders.展开更多
基金supported by the National Natural Science Foundation of China (No. 21372257)the National Basic Research Program of China (973 Program, No. 2010CB126104)+1 种基金the Natural Sciences and Engineering Research Council of Canadasupported by China Scholarship Council (CSC) to study in the laboratory of SST at University of Toronto,Canada
文摘Insect growth regulators play an important role in integrated pest management strategies.The FGLa–allatostatins（ASTs）are a family of neuropeptides that can inhibit juvenile hormone（JH）biosynthesis by the corpora allata（CA）of Diploptera punctata in vitro,are regarded as insect growth regulator candidates.In the search for new potential mimics and to explore the effect of linker length on inhibiting JH biosynthesis,a series of AST analogs were synthesized by modifying the linker of K24,which was found to have a significant effect on JH biosynthesis in vitro in our previous study.Functional evaluation demonstrated that all the target compounds can activate the Dippu-Ast R,albeit with different potencies.Analog L6 with the longest linker（n=5）,exhibited not only a promising effect on inhibition of JH biosynthesis both in vitro and in vivo,but also good activity in inhibiting basal oocyte growth.Structure–activity relationships（SAR）studies showed that longer linkers provided greater contribution to activity.
基金supported by the Fundamental Research Funds for the Central Universities(grant number:KJQN201809)the National Natural Science Foundation(grant number:31772185,31972296).
文摘Vitellogenin receptor(VgR)is crucial for vitellogenin(Vg)uptake by oocytes.VgR is less known in Arachnida,especially in spiders.Different from only one VgR in an arthropod species,two VgRs,VgR-1 and VgR-2,were found in the pond wolf spider,Pardosa pseudoannulata.Both VgRs had the typical domains of the low-density lipoprotein receptor family except for the absence of the ligand-binding domain 1 in VgR-2.Spatiotemporal expression profiles showed that two VgR genes were consistently highly expressed in females and their ovaries,but VgR-1 was 48-fold that of VgR-2 in ovaries.The transcriptional level of VgR-1 was significantly downregulated by RNAi,but it did not work for VgR-2 although several trials were performed.Vg-1 and Vg-2 might be the ligands of VgR-1 because their expressions were also decreased in the dsVgR-1-treated females.Silencing VgR-1 prolonged the pre-oviposition period by 56 h.The expression of VgRs and Vgs were upregulated by juvenile hormones(JHs),which suggested that JHs were the essential factors to vitellogenesis in the spider.The present study revealed the importance of VgR-1 in the spider oviposition,which will improve the understanding on VgR physiological functions in spiders.
