To date,more and more transgenic varieties of upland cotton(Gossypium hirsutum L.) generated with transgenes,which derived from varies of alien species,are playing important role in agricultural production.Stacking of...To date,more and more transgenic varieties of upland cotton(Gossypium hirsutum L.) generated with transgenes,which derived from varies of alien species,are playing important role in agricultural production.Stacking of multi-transgenes has a potential for combining all the merits of展开更多
Since the complication of monitoring and evaluating the problems about the transgenic expression and its impacts on the receptor in the transgenic crop breeding and other relevant evaluated works,the authors in the pr...Since the complication of monitoring and evaluating the problems about the transgenic expression and its impacts on the receptor in the transgenic crop breeding and other relevant evaluated works,the authors in the present work tried to assess the differences of spectral parameters of the transgenic rice in contrast with its parent group quantitatively and qualitatively,fulfilling the growth monitoring of the transgenic samples.The spectral parameters(spectral morphological characteristics and indices) chosen are highly related to internal or external stresses to the receipts,and thus could be applied as indicators of biophysical or biochemical processes changes of plant.By ASD portable field spectroradiometer with high-density probe,fine foliar spectra of 8 groups were obtained.By analyzing spectral angle and continuum removal,the spectral morphological differences and their locations of sample spectra were found which could be as auxiliary priori knowledge for quantitative analysis.By investigating spectral indices of the samples,the quantitative differences of spectra were revealed about foliar chlorophyll a+b and carotenoid content.In this study both the spectral differences between transgenic and parent groups and among transgenic groups were investigated.The results show that hyperspectral technique is promising and a helpful auxiliary tool in the study of monitoring the transgenic crop and other relevant researches.By this technique,quantitative and qualitative results of sample spectra could be provided as prior knowledge,as certain orientation,for laboratory professional advanced transgenic breeding study.展开更多
In addition to the negative consequences of climate change,sucking pest complexes severely limited cotton yields in the recent past.Although the damage caused by bollworms was much reduced by utilizing Bt cotton,the e...In addition to the negative consequences of climate change,sucking pest complexes severely limited cotton yields in the recent past.Although the damage caused by bollworms was much reduced by utilizing Bt cotton,the emergence of sucking pests(such as aphids,thrips,and whiteflies)poses a serious threat to cotton production,as they reduce lint yield by 40%–60%finally.Additionally,these pests also caused yield losses by spreading viral diseases.Promoting innovative and thorough control methods is necessary to counter the threat posed by these sucking pests.Such initiatives necessitate a multifaceted strategy that combines next-generation breeding technology and pest management techniques to produce novel cotton cultivars that are resistant to sucking pests.The discovery of novel genes and regulatory factors linked to cotton’s resistance to sucking pests will be possible by the combination of next-generation breeding technologies and omics approaches and employing those tools on special resistant donors.Continuous research aimed at understanding the genetic basis of insect resistance and improving integrated pest management(IPM)techniques is crucial to the sustainability and resilience of cotton cropping systems.To this end,a sustainable and viable strategy to protect cotton fields from sucking pests is outlined.展开更多
Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with des...Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with desirable traits that wouldn’t be possible through conventional breeding methods.Transgenic crops have been developed for various traits globally.Whitefly,Bemisia tabaci(Gennadius)is one of the major sucking pests of cotton that cause significant damage to the cotton production.To combat whitefly infestations,researchers have developed four transgenic cotton lines expressing the fern protein.And those transgenic lines need to be evaluated for their performance against the target pest—whitefly.The evaluation was designed as controlled trials in polyhouse or muslin cloth cages under open-choice and no-choice conditions by comparing four transgenic cotton lines(A,B,C,and D)with three control groups,including untransformed cotton plants with a same genetic background of the transgenic line,conventionally bred whitefly-resistant cotton,and whitefly-susceptible cotton.In order to study the generational effect,the evaluation also involved studies on whitefly development in laboratory,muslin cloth cage,and polyhouse conditions.Results Both open-choice and no-choice experiments had shown that all the four transgenic cotton lines(A,B,C,and D)expressing the fern protein reduced adult whitefly numbers significantly compared with the control lines,except for the no-choice conditions in 2021,where the transgenic line C was non-significant different from the resistant control line.Notably,the nymphal population on the resistant control line was relatively low and nonsignificant different from the transgenic line C in 2021;and the transgenic lines A and C in 2022 under open-choice conditions.Under no-choice condition,the nymphal counts in the resistant control line was non-significant different from transgenic lines C and D in 2021;and transgenic line D in 2022.All transgenic lines showed significant decrease in egg hatching in 2021 and nymphal development in 2022,except for the transgenic line C which had no significant different in the nymphal development comparing with non-transgenic control lines in 2022.Adult emergence rates in both years of evaluation showed significant decrease in transgenic lines A and B comparing with the control lines.Additionally,the results showed a significant reduction in cotton leaf curl disease and sooty mold development in all the four transgenic lines compared with susceptible control under open-choice conditions,indicating potential benefits of transgenic lines beyond direct effect on whitefly control.Furthermore,the research explored the generational effects of the fern protein on whitefly which revealed the lowest fecundity in the transgenic line C across F0,F1 and F3 generations,lower egg hatching in F1 and F2 generations in transgenic lines A and B,shorter nymphal duration in F1 and F2 generations in transgenic line B,and the least total adult emergence in the transgenic line C in F0 and F3 generations.Conclusions These findings suggest that the transgenic cotton lines expressing fern protein disrupts whitefly populations and the life cycle to a certain extent.However,results are not consistent over generations and years of study,indicating these transgenic lines were not superior over control lines and need to be improved in future breeding.展开更多
PiggyBac transposon has demonstrated its long-term and stable transposition on genomes of various species but lacking of the evidence on farm animal genomes. In this study, we constructed a piggyBac transposon marked ...PiggyBac transposon has demonstrated its long-term and stable transposition on genomes of various species but lacking of the evidence on farm animal genomes. In this study, we constructed a piggyBac transposon marked with enhanced green fluorescent protein （eGFP） and showed efficient transposition in porcine somatic cells and cloned embryos. Our results demonstrated that piggyBac transposase could efficiently catalyze transposition in porcine fetal fibroblast cells, as well as in embryos. PiggyBac transposition generated 18-fold more eGFP-positive cell colonies compared to pEGFP-C1 random insertion mutagenesis, but excessive transposase might affect the transfection rate. Also piggyBac mediated 4-fold more eGFP expression than random insertion in cells and 17-fold in cloned embryos at mRNA level. When the mutagenized cells were used for somatic cell nuclear transfer （SCNT）, the cleavage rate and blastocyst rate of constructed embryos harboring piggyBac transposition had no difference with random insertion group. This study provides key information on the piggyBac transposon system as a tool for creating transgenic pigs.展开更多
Engineered minichromosomes have been constructed as novel artificial chromosome platforms for future genetic engineering in maize.We demonstrated that minichromosomes could be created by telomere-mediated chromosomal ...Engineered minichromosomes have been constructed as novel artificial chromosome platforms for future genetic engineering in maize.We demonstrated that minichromosomes could be created by telomere-mediated chromosomal truncation of both normal A chromosomes and the supernumerary展开更多
Background Chitinase is an enzyme that hydrolyzes chitin,a major component of the exoskeleton of insects,including plant pests like whiteflies.The present study aimed to investigate the expression of chemically synthe...Background Chitinase is an enzyme that hydrolyzes chitin,a major component of the exoskeleton of insects,including plant pests like whiteflies.The present study aimed to investigate the expression of chemically synthesized barley ch1 and chi2 genes in cotton(Gossypium hirsutum)through Agrobacterium-mediated transformation.Fifty-five putative transgenic cotton plants were obtained,out of which fifteen plants successfully survived and were shifted to the field.Using gene-specific primers,amplification of 447 bp and 401 bp fragments confirmed the presence of the ch1 and chi2 genes in five transgenic cotton plants of the T0 generation.These five plants were further evalu-ated for their mRNA expression levels.The T0 transgenic cotton plants with the highest mRNA expression level and better yield performance in field,were selected to raise their subsequent progenies.Results The T1 cotton plants showed the highest mRNA expression levels of 3.5-fold in P10(2)for the ch1 gene and 3.7-fold in P2(1)for the chi2 gene.Fluorescent in situ hybridization(FISH)confirmed a single copy number of ch1 and chi2(hemizygous)on chromosome no.6.Furthermore,the efficacy of transgenes on whitefly was evaluated through an insect bioassay,where after 96 h of infestation,mortality rates of whitefly were calculated to be 78%–80%in transgenic cotton plants.The number of eggs on transgenic cotton plants were calculated to be 0.1%–0.12 per plant compared with the non-transgenic plants where egg number was calculated to be 0.90–1.00 per plant.Conclusion Based on these findings,it can be concluded that the chemically synthesized barley chitinase genes(ch1 and chi2)have the potential to be effective against insects with chitin exoskeletons,including whiteflies.The transgenic cotton plants expressing these genes showed increased resistance to whiteflies,resulting in reduced egg numbers and higher mortality rates.展开更多
The domesticated chicken has important roles in basic and applied research. The vector based on scaffold matrix attachment region （S/MAR） appears to be sufficient to maintain long-term expression in an episomal stat...The domesticated chicken has important roles in basic and applied research. The vector based on scaffold matrix attachment region （S/MAR） appears to be sufficient to maintain long-term expression in an episomal state in various mammalian cells. To explore the practical use of episomal vector in transgene technology of agricultural chickens, we fused the S/MAR of the human r-interferon gene into the pEGFP vector and transduced it into chickens by sperm-mediated gene transfer （SMGT）. PCR detection indicated the positive rate of transgene chickens was 60%. The RT-PCR detection and fluorescence observation confirmed the expression of the GFP and indicated the existence of the GFP during the chicken embryogenesis and fetal development. The PCR detection and rescue experiments confirmed the episomal state of the pEPI-EGFP in chick embryos and chicks. These results showed that the S/MAR-based vector could function properly in chicken embryos and was a practicable tool combined with the SMGT to study the development of chickens.展开更多
OBJECTIVE To explore the potential effect and mechanisms of protopanaxadiol deriva.tive 1-(3,4-dimethoxyphenethyl)-3-(3-dehydroxyl-20(s)-protopa-naxadiol-3 b-yl)-urea(DDPU) in the treatment of Alzheimer disease.METHOD...OBJECTIVE To explore the potential effect and mechanisms of protopanaxadiol deriva.tive 1-(3,4-dimethoxyphenethyl)-3-(3-dehydroxyl-20(s)-protopa-naxadiol-3 b-yl)-urea(DDPU) in the treatment of Alzheimer disease.METHODS ELISA assay was performed in both HEK293-APPswe and CHO-APP cells to demonstrate the efficacy of DDPU in reducing Ab level.SH-SY5 Y,primary neurons and astrocyte cellswereused to study the regulation of DDPU against the signaling pathways involved in Aβ/ER-stress pathology.APP/PS1 transgenic mice wereusedto study the regulation of DDPU against ADL and cognitive deficits.APP/PS1 transgenic mice were randomly placed into three groups(n=10):The two 6-month transgenic groups were administrated with 30 mg·kg^(-1) DDPU or vehicle and the 6-month non-transgenic group was administrated with vehicle for 100 days by intraperitonealinjec.tion.After 100-day administration,nest construction assay and Morris water maze(MWM) assay were applied to evaluate the daily living activities and cognitive abilities of the mice with continuous DDPU treatment.Upon completion of behavior assays,mice were euthanized,and the brains were removed and bisected in mid-sagittal plane.The right hemispheres were frozen and stored at-80°C,and the left hemispheres were fixed in 4% paraformaldehyde.RESULTS DDPU effectively improved learning and memory impairments in APP/PS1 transgenic mice,and the underlying mechanisms have been inten.sively investigated.DDPU reduced Ab production by inhibiting the PERK/eIF2 a signaling-mediated BACE1 translation,while promoted Ab clearance as a PI3K inhibitor thus negatively regulating PI3K/AKT/mTOR signaling in promotion of autophagy.Moreover,DDPU also exhibited neuroprotective effect by attenuating ER stress.Therefore,all findings have clearly demonstrated the crosstalk between Ab and ER stress,and confirmed that targeting ER stress should be a potential target for innovative anti-AD drug development,while highlighted the potential of DDPU in the treatment of AD.展开更多
TaqMan quantitative PCR technique was used to detect the copies of exogenous CaMV35S flanks sequence in transgenic soybean. With soybean lectin as the endogenous reference gene, and gene complex DNA in non-GMO soybean...TaqMan quantitative PCR technique was used to detect the copies of exogenous CaMV35S flanks sequence in transgenic soybean. With soybean lectin as the endogenous reference gene, and gene complex DNA in non-GMO soybeans as the endogenous reference standard, the gradient dilution method was used to separately calculate Ct value of endogenous reference gene and plasmid DNA and correlation standard curve equation of logarithm of copies, and then to calculate the copies of samples through substituting thus-obtained Ct into the standard curve equation. The standard curve equation of endogenous reference gene was y =–3.422x＋35.201, R2=0.998; the standard curve equation of exogenous gene was y =–3.495x＋35.303, R2=0.999. The sample copies was got by putting Ct value into the standard curve equation, and it was the ratio of exogenous gene and reference gene. We found that CaMV35S gene in transgenic soy was single copy.展开更多
Working on screening and identification of moreimportant genes will improve understanding ofthe fiber development mechanism and may alsolead to the development of transgenic cotton thatcould improve cotton fiber quant...Working on screening and identification of moreimportant genes will improve understanding ofthe fiber development mechanism and may alsolead to the development of transgenic cotton thatcould improve cotton fiber quantity and quality.Many efforts have been directed toward theisolation of fiber specific genes,however,only afew genes have been cloned out of the展开更多
Dongnong50 was overexpressing TaDREB3, a stress-tolerance gene, and transgenic progenies with TaDREB3 showing stable heredity characters were obtained in this study. The seeds of T4 generation were sowed on saline lan...Dongnong50 was overexpressing TaDREB3, a stress-tolerance gene, and transgenic progenies with TaDREB3 showing stable heredity characters were obtained in this study. The seeds of T4 generation were sowed on saline land of which salt concentration was 0.19% and pH was 8.43, and agronomic traits including growth period, plant height, numbers of main nodes, branching numbers, pods per plant, numbers of seeds per plant, and weight of 100-seed were collected and comparing to control plants Dongnong50 were made. The impacts of TaDREB3 gene on agronomic traits of soybeans under high concentration of salt were discussed. The results showed that the growth period was not altered in transgenic line with TaDREB3 under high concentration of saline and alkali, the extremely significant or significant increase in the numbers of main nodes, pods per plant and in branching numbers and other agronomic traits in transgenic lines in comparing with non-transgenic lines was an indicator of their resistance to saline-alkali stress展开更多
A PCR-ELISA method for detecting the glyphosate resistant transgenic soybean was established and optimized. The results showed that the key parameters of PCR-ELISA were as follows： the concentration of digoxin tag pr...A PCR-ELISA method for detecting the glyphosate resistant transgenic soybean was established and optimized. The results showed that the key parameters of PCR-ELISA were as follows： the concentration of digoxin tag probe was 0.5 μmol · L^-1, the time of hybridization reaction was 15 min and the chromogenic reaction should last for 30 min. The sensitivity and the repeatability of our PCR-ELISA method were evaluated, and the results showed that it could be detected when the concentration of DNA template from transgenic soybean samples was 0.01% or higher, and the coefficient of variation of this method was less than 5% in our research condition. These results suggested that PCR-ELISA method establishment in this study had good repeatability and high precision for detecting the transgenic soybean samples.展开更多
Background:Soil salinity seriously affects cotton growth,leading to the reduction of yield and fiber quality.Recently,genetic engineering has become an efficient tool to increase abiotic stress tolerance in crops.Resu...Background:Soil salinity seriously affects cotton growth,leading to the reduction of yield and fiber quality.Recently,genetic engineering has become an efficient tool to increase abiotic stress tolerance in crops.Results:In this study,isopentyl transferase(IPT),a key enzyme involved in cytokinin(CTK) biosynthesis from Agrobacterium tumefaciens,was selected to generate transgenic cotton via Agrobacterium-mediated transformation.A senescence-inducible SAG12 promoter from Arabidopsis was fused with the IPT gene.Ectopic-expression of SAG12::IPT significantly promoted seed germination or seedling tolerance to salt stress.Two IPTtransgenic lines,OE3 as a tolerant line during seed germination,and OE8 as a tolerant line at seedling stage,were selected for further physiological analysis.The data showed that ectopic-expression of SAG12::IPT induced the accumulation of CTKs not only in leaves and roots,but also in germinating seeds.Moreover,ectopic-expressing IPT increased the activity of antioxidant enzymes,which was associated with the less reactive oxygen species(ROS) accumulation compared with control plants.Also,ectopic-expression of IPT produced higher K^+/Na^+ratio in cotton shoot and root Conclusion:The senescence-induced CTK accumulation in cotton seeds and seedlings positively regulates salt stress partially by elevating ROS scavenging capability.展开更多
OBJECTIVE Transgenic mouse model has been widely used in pathogenesis study and preclinical drug evaluation in Alzheimer disease(AD).However,key differences are found between current animal models and clinical AD pati...OBJECTIVE Transgenic mouse model has been widely used in pathogenesis study and preclinical drug evaluation in Alzheimer disease(AD).However,key differences are found between current animal models and clinical AD patients regarding phenotypes.Lack of complete models that recapitulate broad spectrum of human AD neuropathology restricts efficacy of research projects and leads to frequent failure in AD drug development at clinical trial stages.This study aims to develop better mouse models of AD through modifying key phenotype insufficiency.METHODS By crossing different single and double transgenic mice with different mutations of APP/PS1 or tau and under prion,Thy1 or PDGF-β promoter,as well as selected knockout mice,I produced a dozen of bigenic models for neuropathology screening.Further neurochemical,behavioral and pharmacological validations were conducted in the optimized mouse model.RESULTS Neuropathology phenotyping found remarkable differences in tau pathology and neurodegeneration among individual APP/PS1/tau transgenic models.I had identified a triple mouse model named FADT that showed(1) huge mature tau pathology in hippocampus and cortex;(2) abundant tau truncation,as seen in human AD brain;(3)progressive neurodegeneration;(4)selective brain atrophy in hippocampus and entorhinal cortex;(5) reproducible and late onset spatial memory defects,etc.Importantly,remarkable tau pathology in this FADT model is mainly driven by beta-amyloid pathology,which differs from high expression of tau in rTg4510 model.CONCLUSION I had developed a new triple transgenic mouse model that recapitulates broad spectrum of human AD neuropathology features.This study will not only establish a solid model basis for AD pathophysiology investigation and drug development,but also reveal important clues on the interaction of beta-amyloid and tau pathologies in the brain.展开更多
Apolipoprotein CⅢ(ApoCⅢ)has been implicated in hypertriglyceridemia and plasma ApoCⅢ is independently predicted as risk factor for coronary heart disease.Hypertriglyceridemia in patients are demonstrated to correla...Apolipoprotein CⅢ(ApoCⅢ)has been implicated in hypertriglyceridemia and plasma ApoCⅢ is independently predicted as risk factor for coronary heart disease.Hypertriglyceridemia in patients are demonstrated to correlate with elevated plasma ApoCⅢ levels and reduced lipoprotein lipase(LPL)activity,while展开更多
OBJECTIVE Alzheimer disease(AD) is the most common type of senile dementia. The anti-aging gene Klotho is reported to decline in the brain of patients and animals with AD. However, the role of Klotho in the progressio...OBJECTIVE Alzheimer disease(AD) is the most common type of senile dementia. The anti-aging gene Klotho is reported to decline in the brain of patients and animals with AD. However, the role of Klotho in the progression of AD remains elusive. The present study explored the effects and underlying mechanism of Klotho in amyloid precursor protein/presenilin 1(APP/PS1) transgenic mice. METHODS The upregulation of cerebral Klotho expression was mediated by intracerebroventricular administration of a lentiviral vector that encoded Klotho(LV-KL) in APP/PS1 transgenicmice.RESULTS LV-KL significantly increased Klotho overexpression and effectively ameliorated cognitive deficits and AD-like pathology in aged AD mice. LV-KL might induce autophagy activation and protein kinase B/mammalian target of rapamycin inhibition in both AD mice and cultured BV2 murine microglia. Meanwhile, LV-KL altered the expression of low density lipoprotein receptor-related protein 1(LRP-1), receptor for advanced glycation end products, P-glycoprotein and ABCA1 both at the brain microvascular and choroid plexus as well as the contents of plasma s LRP-1 in aged AD mice.CONCLUSION The current results indicate that Klotho plays a crucial role in the clearance of cerebral amyloid β protein and the progression of AD in mice. These findings highlight the preventive and therapeutic potential of Klotho for the treatment of AD.展开更多
Verticillium(V.dahliae Kleb.) and Fusarium(F.Oxysporum f.sp.vasinfectum)wilt aretwo major fungal diseases in cotton productionwhich cause great crop damage and yield lossworld wide.Breeding and application ofresistant...Verticillium(V.dahliae Kleb.) and Fusarium(F.Oxysporum f.sp.vasinfectum)wilt aretwo major fungal diseases in cotton productionwhich cause great crop damage and yield lossworld wide.Breeding and application ofresistant varieties have effectively controlledFusarium wilt.However,the Verticillium wilt-展开更多
Competitions of light,nutrient and water between transgenic glyphosate resistant soybean and weed were evaluated with different herbicides(glyphosate,acetochlor,and the mixture of fomesafen and quizalofop-p-ethyl)in f...Competitions of light,nutrient and water between transgenic glyphosate resistant soybean and weed were evaluated with different herbicides(glyphosate,acetochlor,and the mixture of fomesafen and quizalofop-p-ethyl)in filed,which displayed that the application of the mixture of fomesafen and quizalofop-p-ethyl on soybeans had the best anti-herbicidal effect while glyphosate had the weakest effect.The half-life extended by herbicide mixture would affect the soil nutrients.Weed-soybean competitions affected the absorption of nutrients on soybean and yield.However,effective control of weeds could significantly reduce the weed density,improve the field through different layers of light transmittance and the absorption of nutrients on soybean,and enhance the comprehensive competitiveness of soybean.展开更多
文摘To date,more and more transgenic varieties of upland cotton(Gossypium hirsutum L.) generated with transgenes,which derived from varies of alien species,are playing important role in agricultural production.Stacking of multi-transgenes has a potential for combining all the merits of
基金supported by The Research Grants Council,Hong Kong:Competitive Earmarked Research Grant,No.461907
文摘Since the complication of monitoring and evaluating the problems about the transgenic expression and its impacts on the receptor in the transgenic crop breeding and other relevant evaluated works,the authors in the present work tried to assess the differences of spectral parameters of the transgenic rice in contrast with its parent group quantitatively and qualitatively,fulfilling the growth monitoring of the transgenic samples.The spectral parameters(spectral morphological characteristics and indices) chosen are highly related to internal or external stresses to the receipts,and thus could be applied as indicators of biophysical or biochemical processes changes of plant.By ASD portable field spectroradiometer with high-density probe,fine foliar spectra of 8 groups were obtained.By analyzing spectral angle and continuum removal,the spectral morphological differences and their locations of sample spectra were found which could be as auxiliary priori knowledge for quantitative analysis.By investigating spectral indices of the samples,the quantitative differences of spectra were revealed about foliar chlorophyll a+b and carotenoid content.In this study both the spectral differences between transgenic and parent groups and among transgenic groups were investigated.The results show that hyperspectral technique is promising and a helpful auxiliary tool in the study of monitoring the transgenic crop and other relevant researches.By this technique,quantitative and qualitative results of sample spectra could be provided as prior knowledge,as certain orientation,for laboratory professional advanced transgenic breeding study.
基金M/s.RASI Seeds Pvt.Ltd.,Attur,Tamil Nadu,India for their generous financial assistance in setting up a MAS study in cotton for genetic improvement of sucking pest resistance.
文摘In addition to the negative consequences of climate change,sucking pest complexes severely limited cotton yields in the recent past.Although the damage caused by bollworms was much reduced by utilizing Bt cotton,the emergence of sucking pests(such as aphids,thrips,and whiteflies)poses a serious threat to cotton production,as they reduce lint yield by 40%–60%finally.Additionally,these pests also caused yield losses by spreading viral diseases.Promoting innovative and thorough control methods is necessary to counter the threat posed by these sucking pests.Such initiatives necessitate a multifaceted strategy that combines next-generation breeding technology and pest management techniques to produce novel cotton cultivars that are resistant to sucking pests.The discovery of novel genes and regulatory factors linked to cotton’s resistance to sucking pests will be possible by the combination of next-generation breeding technologies and omics approaches and employing those tools on special resistant donors.Continuous research aimed at understanding the genetic basis of insect resistance and improving integrated pest management(IPM)techniques is crucial to the sustainability and resilience of cotton cropping systems.To this end,a sustainable and viable strategy to protect cotton fields from sucking pests is outlined.
文摘Background Transgenic research in crops involves using genetic engineering techniques to introduce specific genes of interest from other organisms,or even entirely new genes into plant genomes to create crops with desirable traits that wouldn’t be possible through conventional breeding methods.Transgenic crops have been developed for various traits globally.Whitefly,Bemisia tabaci(Gennadius)is one of the major sucking pests of cotton that cause significant damage to the cotton production.To combat whitefly infestations,researchers have developed four transgenic cotton lines expressing the fern protein.And those transgenic lines need to be evaluated for their performance against the target pest—whitefly.The evaluation was designed as controlled trials in polyhouse or muslin cloth cages under open-choice and no-choice conditions by comparing four transgenic cotton lines(A,B,C,and D)with three control groups,including untransformed cotton plants with a same genetic background of the transgenic line,conventionally bred whitefly-resistant cotton,and whitefly-susceptible cotton.In order to study the generational effect,the evaluation also involved studies on whitefly development in laboratory,muslin cloth cage,and polyhouse conditions.Results Both open-choice and no-choice experiments had shown that all the four transgenic cotton lines(A,B,C,and D)expressing the fern protein reduced adult whitefly numbers significantly compared with the control lines,except for the no-choice conditions in 2021,where the transgenic line C was non-significant different from the resistant control line.Notably,the nymphal population on the resistant control line was relatively low and nonsignificant different from the transgenic line C in 2021;and the transgenic lines A and C in 2022 under open-choice conditions.Under no-choice condition,the nymphal counts in the resistant control line was non-significant different from transgenic lines C and D in 2021;and transgenic line D in 2022.All transgenic lines showed significant decrease in egg hatching in 2021 and nymphal development in 2022,except for the transgenic line C which had no significant different in the nymphal development comparing with non-transgenic control lines in 2022.Adult emergence rates in both years of evaluation showed significant decrease in transgenic lines A and B comparing with the control lines.Additionally,the results showed a significant reduction in cotton leaf curl disease and sooty mold development in all the four transgenic lines compared with susceptible control under open-choice conditions,indicating potential benefits of transgenic lines beyond direct effect on whitefly control.Furthermore,the research explored the generational effects of the fern protein on whitefly which revealed the lowest fecundity in the transgenic line C across F0,F1 and F3 generations,lower egg hatching in F1 and F2 generations in transgenic lines A and B,shorter nymphal duration in F1 and F2 generations in transgenic line B,and the least total adult emergence in the transgenic line C in F0 and F3 generations.Conclusions These findings suggest that the transgenic cotton lines expressing fern protein disrupts whitefly populations and the life cycle to a certain extent.However,results are not consistent over generations and years of study,indicating these transgenic lines were not superior over control lines and need to be improved in future breeding.
基金Supported by the National Projects of Genetic Modified Organism Breeding Technology (2008ZX08006-002)the State Transgenic Research Programme of China (2008ZX08006-002)
文摘PiggyBac transposon has demonstrated its long-term and stable transposition on genomes of various species but lacking of the evidence on farm animal genomes. In this study, we constructed a piggyBac transposon marked with enhanced green fluorescent protein （eGFP） and showed efficient transposition in porcine somatic cells and cloned embryos. Our results demonstrated that piggyBac transposase could efficiently catalyze transposition in porcine fetal fibroblast cells, as well as in embryos. PiggyBac transposition generated 18-fold more eGFP-positive cell colonies compared to pEGFP-C1 random insertion mutagenesis, but excessive transposase might affect the transfection rate. Also piggyBac mediated 4-fold more eGFP expression than random insertion in cells and 17-fold in cloned embryos at mRNA level. When the mutagenized cells were used for somatic cell nuclear transfer （SCNT）, the cleavage rate and blastocyst rate of constructed embryos harboring piggyBac transposition had no difference with random insertion group. This study provides key information on the piggyBac transposon system as a tool for creating transgenic pigs.
文摘Engineered minichromosomes have been constructed as novel artificial chromosome platforms for future genetic engineering in maize.We demonstrated that minichromosomes could be created by telomere-mediated chromosomal truncation of both normal A chromosomes and the supernumerary
文摘Background Chitinase is an enzyme that hydrolyzes chitin,a major component of the exoskeleton of insects,including plant pests like whiteflies.The present study aimed to investigate the expression of chemically synthesized barley ch1 and chi2 genes in cotton(Gossypium hirsutum)through Agrobacterium-mediated transformation.Fifty-five putative transgenic cotton plants were obtained,out of which fifteen plants successfully survived and were shifted to the field.Using gene-specific primers,amplification of 447 bp and 401 bp fragments confirmed the presence of the ch1 and chi2 genes in five transgenic cotton plants of the T0 generation.These five plants were further evalu-ated for their mRNA expression levels.The T0 transgenic cotton plants with the highest mRNA expression level and better yield performance in field,were selected to raise their subsequent progenies.Results The T1 cotton plants showed the highest mRNA expression levels of 3.5-fold in P10(2)for the ch1 gene and 3.7-fold in P2(1)for the chi2 gene.Fluorescent in situ hybridization(FISH)confirmed a single copy number of ch1 and chi2(hemizygous)on chromosome no.6.Furthermore,the efficacy of transgenes on whitefly was evaluated through an insect bioassay,where after 96 h of infestation,mortality rates of whitefly were calculated to be 78%–80%in transgenic cotton plants.The number of eggs on transgenic cotton plants were calculated to be 0.1%–0.12 per plant compared with the non-transgenic plants where egg number was calculated to be 0.90–1.00 per plant.Conclusion Based on these findings,it can be concluded that the chemically synthesized barley chitinase genes(ch1 and chi2)have the potential to be effective against insects with chitin exoskeletons,including whiteflies.The transgenic cotton plants expressing these genes showed increased resistance to whiteflies,resulting in reduced egg numbers and higher mortality rates.
基金Supported by the National Natural Science Foundation of China(31101033)the Doctoral Research Foundation of Northeast Agricultural University(2009RC56)the Scientific Research Fund of Heilongjiang Provincial Education Department(11551039)
文摘The domesticated chicken has important roles in basic and applied research. The vector based on scaffold matrix attachment region （S/MAR） appears to be sufficient to maintain long-term expression in an episomal state in various mammalian cells. To explore the practical use of episomal vector in transgene technology of agricultural chickens, we fused the S/MAR of the human r-interferon gene into the pEGFP vector and transduced it into chickens by sperm-mediated gene transfer （SMGT）. PCR detection indicated the positive rate of transgene chickens was 60%. The RT-PCR detection and fluorescence observation confirmed the expression of the GFP and indicated the existence of the GFP during the chicken embryogenesis and fetal development. The PCR detection and rescue experiments confirmed the episomal state of the pEPI-EGFP in chick embryos and chicks. These results showed that the S/MAR-based vector could function properly in chicken embryos and was a practicable tool combined with the SMGT to study the development of chickens.
基金supported by National Natural Science Foundation of China(81220108025,81473141) NSFC-TRF collaboration projects(81561148011,DBG5980001)+3 种基金 Drug Innovation Project of SIMM(CASIMM0120154035) Personalized Medicine-Molecular Signature-based Drug Discovery and Development, Strategic Priority Research Program of Chinese Academy of Sciences (XDA12040303) the Project Funded by the Priority Aca-demic Program Development of Jiangsu Higher Education Institutions (Integration of Chinese and Western Medi-cine17KJA350002) National Natural Science Foundation for Young Scientists of China (81703806)
文摘OBJECTIVE To explore the potential effect and mechanisms of protopanaxadiol deriva.tive 1-(3,4-dimethoxyphenethyl)-3-(3-dehydroxyl-20(s)-protopa-naxadiol-3 b-yl)-urea(DDPU) in the treatment of Alzheimer disease.METHODS ELISA assay was performed in both HEK293-APPswe and CHO-APP cells to demonstrate the efficacy of DDPU in reducing Ab level.SH-SY5 Y,primary neurons and astrocyte cellswereused to study the regulation of DDPU against the signaling pathways involved in Aβ/ER-stress pathology.APP/PS1 transgenic mice wereusedto study the regulation of DDPU against ADL and cognitive deficits.APP/PS1 transgenic mice were randomly placed into three groups(n=10):The two 6-month transgenic groups were administrated with 30 mg·kg^(-1) DDPU or vehicle and the 6-month non-transgenic group was administrated with vehicle for 100 days by intraperitonealinjec.tion.After 100-day administration,nest construction assay and Morris water maze(MWM) assay were applied to evaluate the daily living activities and cognitive abilities of the mice with continuous DDPU treatment.Upon completion of behavior assays,mice were euthanized,and the brains were removed and bisected in mid-sagittal plane.The right hemispheres were frozen and stored at-80°C,and the left hemispheres were fixed in 4% paraformaldehyde.RESULTS DDPU effectively improved learning and memory impairments in APP/PS1 transgenic mice,and the underlying mechanisms have been inten.sively investigated.DDPU reduced Ab production by inhibiting the PERK/eIF2 a signaling-mediated BACE1 translation,while promoted Ab clearance as a PI3K inhibitor thus negatively regulating PI3K/AKT/mTOR signaling in promotion of autophagy.Moreover,DDPU also exhibited neuroprotective effect by attenuating ER stress.Therefore,all findings have clearly demonstrated the crosstalk between Ab and ER stress,and confirmed that targeting ER stress should be a potential target for innovative anti-AD drug development,while highlighted the potential of DDPU in the treatment of AD.
基金Supported by the Program of Technology Bureau of Harbin (2010RFQXN101)the Subproject of Transgenic Significant Specific Project (20112X08004-002-002-004)
文摘TaqMan quantitative PCR technique was used to detect the copies of exogenous CaMV35S flanks sequence in transgenic soybean. With soybean lectin as the endogenous reference gene, and gene complex DNA in non-GMO soybeans as the endogenous reference standard, the gradient dilution method was used to separately calculate Ct value of endogenous reference gene and plasmid DNA and correlation standard curve equation of logarithm of copies, and then to calculate the copies of samples through substituting thus-obtained Ct into the standard curve equation. The standard curve equation of endogenous reference gene was y =–3.422x＋35.201, R2=0.998; the standard curve equation of exogenous gene was y =–3.495x＋35.303, R2=0.999. The sample copies was got by putting Ct value into the standard curve equation, and it was the ratio of exogenous gene and reference gene. We found that CaMV35S gene in transgenic soy was single copy.
文摘Working on screening and identification of moreimportant genes will improve understanding ofthe fiber development mechanism and may alsolead to the development of transgenic cotton thatcould improve cotton fiber quantity and quality.Many efforts have been directed toward theisolation of fiber specific genes,however,only afew genes have been cloned out of the
基金Supported by Project of Education Department of Heilongjiang Province (11551048)
文摘Dongnong50 was overexpressing TaDREB3, a stress-tolerance gene, and transgenic progenies with TaDREB3 showing stable heredity characters were obtained in this study. The seeds of T4 generation were sowed on saline land of which salt concentration was 0.19% and pH was 8.43, and agronomic traits including growth period, plant height, numbers of main nodes, branching numbers, pods per plant, numbers of seeds per plant, and weight of 100-seed were collected and comparing to control plants Dongnong50 were made. The impacts of TaDREB3 gene on agronomic traits of soybeans under high concentration of salt were discussed. The results showed that the growth period was not altered in transgenic line with TaDREB3 under high concentration of saline and alkali, the extremely significant or significant increase in the numbers of main nodes, pods per plant and in branching numbers and other agronomic traits in transgenic lines in comparing with non-transgenic lines was an indicator of their resistance to saline-alkali stress
文摘A PCR-ELISA method for detecting the glyphosate resistant transgenic soybean was established and optimized. The results showed that the key parameters of PCR-ELISA were as follows： the concentration of digoxin tag probe was 0.5 μmol · L^-1, the time of hybridization reaction was 15 min and the chromogenic reaction should last for 30 min. The sensitivity and the repeatability of our PCR-ELISA method were evaluated, and the results showed that it could be detected when the concentration of DNA template from transgenic soybean samples was 0.01% or higher, and the coefficient of variation of this method was less than 5% in our research condition. These results suggested that PCR-ELISA method establishment in this study had good repeatability and high precision for detecting the transgenic soybean samples.
基金supported by The Genetically Modified Organisms Breeding Major Projects of China Grant(2016ZX08005-004)
文摘Background:Soil salinity seriously affects cotton growth,leading to the reduction of yield and fiber quality.Recently,genetic engineering has become an efficient tool to increase abiotic stress tolerance in crops.Results:In this study,isopentyl transferase(IPT),a key enzyme involved in cytokinin(CTK) biosynthesis from Agrobacterium tumefaciens,was selected to generate transgenic cotton via Agrobacterium-mediated transformation.A senescence-inducible SAG12 promoter from Arabidopsis was fused with the IPT gene.Ectopic-expression of SAG12::IPT significantly promoted seed germination or seedling tolerance to salt stress.Two IPTtransgenic lines,OE3 as a tolerant line during seed germination,and OE8 as a tolerant line at seedling stage,were selected for further physiological analysis.The data showed that ectopic-expression of SAG12::IPT induced the accumulation of CTKs not only in leaves and roots,but also in germinating seeds.Moreover,ectopic-expressing IPT increased the activity of antioxidant enzymes,which was associated with the less reactive oxygen species(ROS) accumulation compared with control plants.Also,ectopic-expression of IPT produced higher K^+/Na^+ratio in cotton shoot and root Conclusion:The senescence-induced CTK accumulation in cotton seeds and seedlings positively regulates salt stress partially by elevating ROS scavenging capability.
基金Science and Technology Development Fund of Shanghai Pudong New District (PKJ2017-Y37)Shanghai Natural Science Foundation(18ZR1417900).
文摘OBJECTIVE Transgenic mouse model has been widely used in pathogenesis study and preclinical drug evaluation in Alzheimer disease(AD).However,key differences are found between current animal models and clinical AD patients regarding phenotypes.Lack of complete models that recapitulate broad spectrum of human AD neuropathology restricts efficacy of research projects and leads to frequent failure in AD drug development at clinical trial stages.This study aims to develop better mouse models of AD through modifying key phenotype insufficiency.METHODS By crossing different single and double transgenic mice with different mutations of APP/PS1 or tau and under prion,Thy1 or PDGF-β promoter,as well as selected knockout mice,I produced a dozen of bigenic models for neuropathology screening.Further neurochemical,behavioral and pharmacological validations were conducted in the optimized mouse model.RESULTS Neuropathology phenotyping found remarkable differences in tau pathology and neurodegeneration among individual APP/PS1/tau transgenic models.I had identified a triple mouse model named FADT that showed(1) huge mature tau pathology in hippocampus and cortex;(2) abundant tau truncation,as seen in human AD brain;(3)progressive neurodegeneration;(4)selective brain atrophy in hippocampus and entorhinal cortex;(5) reproducible and late onset spatial memory defects,etc.Importantly,remarkable tau pathology in this FADT model is mainly driven by beta-amyloid pathology,which differs from high expression of tau in rTg4510 model.CONCLUSION I had developed a new triple transgenic mouse model that recapitulates broad spectrum of human AD neuropathology features.This study will not only establish a solid model basis for AD pathophysiology investigation and drug development,but also reveal important clues on the interaction of beta-amyloid and tau pathologies in the brain.
文摘Apolipoprotein CⅢ(ApoCⅢ)has been implicated in hypertriglyceridemia and plasma ApoCⅢ is independently predicted as risk factor for coronary heart disease.Hypertriglyceridemia in patients are demonstrated to correlate with elevated plasma ApoCⅢ levels and reduced lipoprotein lipase(LPL)activity,while
文摘OBJECTIVE Alzheimer disease(AD) is the most common type of senile dementia. The anti-aging gene Klotho is reported to decline in the brain of patients and animals with AD. However, the role of Klotho in the progression of AD remains elusive. The present study explored the effects and underlying mechanism of Klotho in amyloid precursor protein/presenilin 1(APP/PS1) transgenic mice. METHODS The upregulation of cerebral Klotho expression was mediated by intracerebroventricular administration of a lentiviral vector that encoded Klotho(LV-KL) in APP/PS1 transgenicmice.RESULTS LV-KL significantly increased Klotho overexpression and effectively ameliorated cognitive deficits and AD-like pathology in aged AD mice. LV-KL might induce autophagy activation and protein kinase B/mammalian target of rapamycin inhibition in both AD mice and cultured BV2 murine microglia. Meanwhile, LV-KL altered the expression of low density lipoprotein receptor-related protein 1(LRP-1), receptor for advanced glycation end products, P-glycoprotein and ABCA1 both at the brain microvascular and choroid plexus as well as the contents of plasma s LRP-1 in aged AD mice.CONCLUSION The current results indicate that Klotho plays a crucial role in the clearance of cerebral amyloid β protein and the progression of AD in mice. These findings highlight the preventive and therapeutic potential of Klotho for the treatment of AD.
文摘Verticillium(V.dahliae Kleb.) and Fusarium(F.Oxysporum f.sp.vasinfectum)wilt aretwo major fungal diseases in cotton productionwhich cause great crop damage and yield lossworld wide.Breeding and application ofresistant varieties have effectively controlledFusarium wilt.However,the Verticillium wilt-
基金Supported by Environmental Safety Assessment of Key Research Projects of Ministry of Agriculture(2016ZX08011-003)
文摘Competitions of light,nutrient and water between transgenic glyphosate resistant soybean and weed were evaluated with different herbicides(glyphosate,acetochlor,and the mixture of fomesafen and quizalofop-p-ethyl)in filed,which displayed that the application of the mixture of fomesafen and quizalofop-p-ethyl on soybeans had the best anti-herbicidal effect while glyphosate had the weakest effect.The half-life extended by herbicide mixture would affect the soil nutrients.Weed-soybean competitions affected the absorption of nutrients on soybean and yield.However,effective control of weeds could significantly reduce the weed density,improve the field through different layers of light transmittance and the absorption of nutrients on soybean,and enhance the comprehensive competitiveness of soybean.
