Lycosidae females demonstrate meticulous maternal care of offspring by carrying egg sacs and juvenile spiderlings during the reproductive stage. Nuclear receptors(NRs), especially the ecdysone receptor(EcR) and ultras...Lycosidae females demonstrate meticulous maternal care of offspring by carrying egg sacs and juvenile spiderlings during the reproductive stage. Nuclear receptors(NRs), especially the ecdysone receptor(EcR) and ultraspiracle(USP), have attracted considerable attention in the regulation of arthropod development and reproduction due to their pivotal roles in ecdysteroid signaling cascades. In the present study, 23 NRs, including one EcR and two USPs, were identified in the genome of the predatory wolf spider Pardosa pseudoannulata. RNA interference(RNAi) targeting EcR and USP-1inhibited spiderling development and resulted in nonviable eggs in the egg sacs. EcR and USP-1responded to changes in ecdysteroid levels, and interference in ecdysteroid biosynthesis led to similar phenotypes as ds EcR and ds USP-1 treatments.These findings suggest that EcR/USP-1-mediated ecdysteroid signaling regulates P. pseudoannulata development and reproduction. The P.pseudoannulata females with suppressed ecdysteroid signaling proactively consumed their non-viable egg sacs, resulting in a 7.19 d shorter first reproductive cycle than the controls. Termination of the failed reproductive cycle enabled the spiders to produce a new egg sac more rapidly. This reproductive strategy may partially rescue the reduction in population growth due to non-viable eggs and compensate for the physiological expenditure of wasted maternal care, which would be beneficial for the conservation of P.pseudoannulata populations and their natural control of insect pests.展开更多
Objective To study the effect of Asparagus officinalis polysaccharide on the number and activity of erythrocyte complement receptor 1 in S180 mice.Methods Red blood cells from mice venous blood were labeled by rat ant...Objective To study the effect of Asparagus officinalis polysaccharide on the number and activity of erythrocyte complement receptor 1 in S180 mice.Methods Red blood cells from mice venous blood were labeled by rat anti-mouse CD35 monoclonal antibody and FITC-conjugated goat anti-mouse antibody.Using flow cytometry,we determined the number of ECR1.Using microscope,we studied the adherence between erythrocyte immunity and C3b receptor or tumor-cell by RBC-C3bRR and DTER.Results Comparing the mean value of the number of CR1 on each RBC of high and middle groups with control groups,the mean value of the number of CR1,RBC-C3bRR and DTER of Asparagus officinalis polysaccharide groups are increased significantly.Conclusions Asparagus officinalis polysaccharide can improve the erythrocyte function of S180 mice,which may be one of its most important antitumor mechanisms.展开更多
Henosepilachna vigintioctopunctata is a serious insect pest which attacks a large number of nightshades and cucurbits in Asian countries,Brazil and Australia.Prolonged application of traditional pesticides has caused ...Henosepilachna vigintioctopunctata is a serious insect pest which attacks a large number of nightshades and cucurbits in Asian countries,Brazil and Australia.Prolonged application of traditional pesticides has caused environmental pollution and exerted deleterious effects on human health.Finding new approaches with high target specificity and low environmental contamination has become an urgent task.RNA interference(RNAi)induced by double-stranded RNA(dsRNA)is expected to be applicable to managing this pest.Here we evaluated the effects of Escherichia co/Z-expressed dsRNAs targeting ecdvsone receptor(EcR)gene via dietary delivery in laboratory and foliar spraying in a greenhouse.The target transcript was successfully knocked down when the 4th-instar larvae had fed on potatofoliage dipped with dsEcR in a laboratory bioassay.Around 85%of the HvEcR RNAi larvae remained as prepupae or became abnormal pupae,and failed to emerge into adults.Ingestion of ds£c7?-immersed foliage by the 3rd-instar larvae effectuated a comparable RNAi response and brought about more severe defects:all the resultant larvae arrested development,remained as prepupae and finally died.For assay in the greenhouse,a ds£c7?-contained E.coli suspension was directly sprayed to the foliage of greenhouse-growing potato plants and the 3rd-and 4th-instar larvae were transferred to the leaves.High RNAi efficacy was obtained and identical RNAi phenotypes were observed in treated larvae.In addition,spraying dsEcR reduced leaf damage.Our results indicate a possibility of practical application of dsEcR as an environmentally friendly RNA pesticide to control H.vigintioctopunctata larvae.展开更多
A heterodimer of two nuclear receptors,ecdysone receptor(EcR)and ultraspiracle,mediates 20‐hydroxyecdysone(20E)signaling to modulate many aspects in insect life,such as molting and metamorphosis,reproduction,diapause...A heterodimer of two nuclear receptors,ecdysone receptor(EcR)and ultraspiracle,mediates 20‐hydroxyecdysone(20E)signaling to modulate many aspects in insect life,such as molting and metamorphosis,reproduction,diapause and innate immunity.In the present paper,we intended to determine the isoform‐specific roles of EcR during larval–pupal–adult transition in the Colorado potato beetle.Double‐stranded RNAs(dsRNAs)were prepared using the common(dsEcR)or isoform‐specific(dsEcRA,dsEcRB1)regions of EcR as templates.Ingestion of either dsEcR or dsEcRA,rather than dsEcRB1,by the penultimate(3rd)and final(4th)instar larvae caused failure of larval–pupal and pupal–adult ecdysis.The RNA interference(RNAi)larvae remained as prepupae,or became deformed pupae and adults.Determination of messenger RNA(mRNA)levels of EcR isoforms found that LdEcRA regulates the expression of LdEcRB1.Moreover,silencing the two EcR transcripts,LdEcRA or LdEcRB1 reduced the mRNA levels of Ldspo and Ldsad,and lowered 20E titer.In contrast,the expression levels of HR3,HR4,E74 and E75 were significantly decreased in the LdEcR or LdEcRA RNAi larvae,but not in LdEcRB1 depleted specimens.Dietary supplement with 20E did not restore the expression of five 20E signaling genes(USP,HR3,HR4,E74 and E75),and only partially alleviated the pupation defects in dsEcR‐or dsEcRA‐fed beetles.These data suggest that EcR plays isoform‐specific roles in the regulation of ecdysteroidogenesis and the transduction of 20E signal in L.decemlineata.展开更多
基金supported by the National Natural Science Foundation of China(31972296,32172482)。
文摘Lycosidae females demonstrate meticulous maternal care of offspring by carrying egg sacs and juvenile spiderlings during the reproductive stage. Nuclear receptors(NRs), especially the ecdysone receptor(EcR) and ultraspiracle(USP), have attracted considerable attention in the regulation of arthropod development and reproduction due to their pivotal roles in ecdysteroid signaling cascades. In the present study, 23 NRs, including one EcR and two USPs, were identified in the genome of the predatory wolf spider Pardosa pseudoannulata. RNA interference(RNAi) targeting EcR and USP-1inhibited spiderling development and resulted in nonviable eggs in the egg sacs. EcR and USP-1responded to changes in ecdysteroid levels, and interference in ecdysteroid biosynthesis led to similar phenotypes as ds EcR and ds USP-1 treatments.These findings suggest that EcR/USP-1-mediated ecdysteroid signaling regulates P. pseudoannulata development and reproduction. The P.pseudoannulata females with suppressed ecdysteroid signaling proactively consumed their non-viable egg sacs, resulting in a 7.19 d shorter first reproductive cycle than the controls. Termination of the failed reproductive cycle enabled the spiders to produce a new egg sac more rapidly. This reproductive strategy may partially rescue the reduction in population growth due to non-viable eggs and compensate for the physiological expenditure of wasted maternal care, which would be beneficial for the conservation of P.pseudoannulata populations and their natural control of insect pests.
文摘Objective To study the effect of Asparagus officinalis polysaccharide on the number and activity of erythrocyte complement receptor 1 in S180 mice.Methods Red blood cells from mice venous blood were labeled by rat anti-mouse CD35 monoclonal antibody and FITC-conjugated goat anti-mouse antibody.Using flow cytometry,we determined the number of ECR1.Using microscope,we studied the adherence between erythrocyte immunity and C3b receptor or tumor-cell by RBC-C3bRR and DTER.Results Comparing the mean value of the number of CR1 on each RBC of high and middle groups with control groups,the mean value of the number of CR1,RBC-C3bRR and DTER of Asparagus officinalis polysaccharide groups are increased significantly.Conclusions Asparagus officinalis polysaccharide can improve the erythrocyte function of S180 mice,which may be one of its most important antitumor mechanisms.
基金This research was supported by the N ational Key R&D Program of China(2017YFD0200900)China A griculture Research System(CARS-09-P22).
文摘Henosepilachna vigintioctopunctata is a serious insect pest which attacks a large number of nightshades and cucurbits in Asian countries,Brazil and Australia.Prolonged application of traditional pesticides has caused environmental pollution and exerted deleterious effects on human health.Finding new approaches with high target specificity and low environmental contamination has become an urgent task.RNA interference(RNAi)induced by double-stranded RNA(dsRNA)is expected to be applicable to managing this pest.Here we evaluated the effects of Escherichia co/Z-expressed dsRNAs targeting ecdvsone receptor(EcR)gene via dietary delivery in laboratory and foliar spraying in a greenhouse.The target transcript was successfully knocked down when the 4th-instar larvae had fed on potatofoliage dipped with dsEcR in a laboratory bioassay.Around 85%of the HvEcR RNAi larvae remained as prepupae or became abnormal pupae,and failed to emerge into adults.Ingestion of ds£c7?-immersed foliage by the 3rd-instar larvae effectuated a comparable RNAi response and brought about more severe defects:all the resultant larvae arrested development,remained as prepupae and finally died.For assay in the greenhouse,a ds£c7?-contained E.coli suspension was directly sprayed to the foliage of greenhouse-growing potato plants and the 3rd-and 4th-instar larvae were transferred to the leaves.High RNAi efficacy was obtained and identical RNAi phenotypes were observed in treated larvae.In addition,spraying dsEcR reduced leaf damage.Our results indicate a possibility of practical application of dsEcR as an environmentally friendly RNA pesticide to control H.vigintioctopunctata larvae.
文摘A heterodimer of two nuclear receptors,ecdysone receptor(EcR)and ultraspiracle,mediates 20‐hydroxyecdysone(20E)signaling to modulate many aspects in insect life,such as molting and metamorphosis,reproduction,diapause and innate immunity.In the present paper,we intended to determine the isoform‐specific roles of EcR during larval–pupal–adult transition in the Colorado potato beetle.Double‐stranded RNAs(dsRNAs)were prepared using the common(dsEcR)or isoform‐specific(dsEcRA,dsEcRB1)regions of EcR as templates.Ingestion of either dsEcR or dsEcRA,rather than dsEcRB1,by the penultimate(3rd)and final(4th)instar larvae caused failure of larval–pupal and pupal–adult ecdysis.The RNA interference(RNAi)larvae remained as prepupae,or became deformed pupae and adults.Determination of messenger RNA(mRNA)levels of EcR isoforms found that LdEcRA regulates the expression of LdEcRB1.Moreover,silencing the two EcR transcripts,LdEcRA or LdEcRB1 reduced the mRNA levels of Ldspo and Ldsad,and lowered 20E titer.In contrast,the expression levels of HR3,HR4,E74 and E75 were significantly decreased in the LdEcR or LdEcRA RNAi larvae,but not in LdEcRB1 depleted specimens.Dietary supplement with 20E did not restore the expression of five 20E signaling genes(USP,HR3,HR4,E74 and E75),and only partially alleviated the pupation defects in dsEcR‐or dsEcRA‐fed beetles.These data suggest that EcR plays isoform‐specific roles in the regulation of ecdysteroidogenesis and the transduction of 20E signal in L.decemlineata.
