Background: In order to uncover the mechanism of significantly reduced insect resistance at the late developmental stage in cotton(Gossypium hirsutum L.),the relationship between boll setting rate under different plan...Background: In order to uncover the mechanism of significantly reduced insect resistance at the late developmental stage in cotton(Gossypium hirsutum L.),the relationship between boll setting rate under different planting densities and Bacillus thuringiensis(Bt)insecticidal concentrations in the boll wall were investigated in the present study.Two studies were arranged at Yangzhou,China during the 2017–2018 cotton growth seasons.Five planting densities(15000,25000,45000,60000 and 75000 plants per hectare)and the flower-removal treatment were imposed separately on Bt cotton cultivar Sikang3 to arrange different boll setting rates,and the boll setting rates and Bt toxin content were compared.Results: Higher boll setting rate together with lower Bt toxin contents in boll wall was observed under low planting density,whereas lower boll setting rate and higher Bt toxin contents were found under high planting density.Also,higher Bt protein concentration was associated with higher soluble protein content,glutamic-pyruvic transaminase(GPT),and glutamic oxaloacetate transaminase(GOT)activities,but lower amino acid content,and protease and peptidase activities.It was further confirmed that a higher boll setting rate with lower Bt protein content under flower-removal.Conclusions: This study demonstrated that the insecticidal efficacy of boll walls was significantly impacted by boll formation.Reduced protein synthesis and enhanced protein degradation were related to the reduced Bt toxin concentration.展开更多
OBJECTIVE To analyze the whole transcriptome of zoanthid Protopalythoa variabilis(P.variabilis),a cnidarian,and discover the potential toxic substances in P.variabilis.METHODS The P.variabilis RNA deep sequencing was ...OBJECTIVE To analyze the whole transcriptome of zoanthid Protopalythoa variabilis(P.variabilis),a cnidarian,and discover the potential toxic substances in P.variabilis.METHODS The P.variabilis RNA deep sequencing was performed using the HiSeq 2500 automatic sequencing platform.All the unigenes generated from the assembly process were functionally annotated based on the similarity with databases.The multiple alignments of translated toxin-related sequences were performed with Clustalw2,and amino acid identity and similarity highlighted by using BoxShade tool.Three different methods including ITASSER,PEP-FOLD and MODELLER were applied to predict tri-dimensional models of toxin-related polypeptides from translated transcript sequences of P.variabilis.The toxicity of one of the putative toxins,namely ShK/Aurelin-like peptide,was evaluated using zebrafish model.RESULTS A total of 67,549,914 pairs of quality-filtered,90-base-pair Illumina reads from an mRNA sample were obtained.The de novo assemblies yielded 276,526 contigs.The sequence comparison of 130,121 unigenes with entries in Toxin database showed that 1542 unigenes were potential peptide toxins at which 11 unigenes were related to Stichodactyla toxin(ShK)domain(Pfam ID:PF01549).ShK is a 35 residues peptide sequence that was firstly discovered from the sea anemone Stichodactyla helianthus.Here,we found out one ShK-like peptide that processed a relatively higher sequence similarity with known ShK(Uniprot ID:P29186)of Bunodosoma granuliferum(red warty sea anemone).The Protopalythoa Shk-like peptide was submitted to Probis server to detect probable binding site and found to match with a protein AURELIN(PDB id:2lg4,UniProt id:Q0MWV8)which possesses structural homology with previously identified antimicrobial peptides and K+-channel-blocking toxins.Our results showed that the ShK/Aurelin-like peptide was lethal to zebrafish embryos at concentrations above 30-μmol·L1,and could induce zebrafish locomotor deficit at 10μmol·L-1.CONCLUSION This study,for the first time,presented the whole transcriptome profile and a potential toxic peptide of P.variabilis.展开更多
Bacillus thuringiensis is a ubiquitous gram-positive, spore-forming bacterium that forms parasporal crystal during the stationary phase of its growth cycle. These crystal proteins, including Cry and Cyt protein, are t...Bacillus thuringiensis is a ubiquitous gram-positive, spore-forming bacterium that forms parasporal crystal during the stationary phase of its growth cycle. These crystal proteins, including Cry and Cyt protein, are toxic to certain insects. Lately, some problems about Cyt classification, structural characteristic, action mechanism and resistance to Cyt toxin are becoming new hotspots. We review the progress of above problems in several foreign labs.展开更多
T-2 toxin is the most widespread mycotoxin in crops,feed and food,which poses a serious threat to body health.Bone is the main target tissue for T-2 toxin accumulation.Ingestion of food contaminated by T-2 toxin is th...T-2 toxin is the most widespread mycotoxin in crops,feed and food,which poses a serious threat to body health.Bone is the main target tissue for T-2 toxin accumulation.Ingestion of food contaminated by T-2 toxin is the main cause of Kashin-Beck disease.However,the specific mechanism of bone damage caused by T-2 toxin is still unclear.In this study,a total of 40 male C57BL/6N mice were divided into four groups and orally treated with 0,0.5,1.0 and 2.0 mg·kg^(-1) body weight T-2 toxin for 28 days.The results showed that exposure to T-2 toxin led to weight loss,bone mineral density reduction and femoral structural damage of mice.In addition,osteoblast-mediated bone formation was inhibited,and osteoclast-mediated bone resorption was enhanced.Meanwhile,the levels of bone metabolism-related hormones including parathyroid hormone,calcitonin and 1,25-dihydroxyvitamin D3 were reduced.More importantly,it was found that the level of neuropeptide Y(a neurohormone)was decreased.These results provided a new perspetive for understanding the osteotoxicity of T-2 toxin.展开更多
基金Natural Science Research of Jiangsu Higher Education Institutions of China(17KJA210003)The Project#31671613 and#31901462 supported by National Natural Science Foundation of China,Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China(PAPD)+1 种基金Natural Science Foundation of Jiangsu Province(BK20191439)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX19_2106).
文摘Background: In order to uncover the mechanism of significantly reduced insect resistance at the late developmental stage in cotton(Gossypium hirsutum L.),the relationship between boll setting rate under different planting densities and Bacillus thuringiensis(Bt)insecticidal concentrations in the boll wall were investigated in the present study.Two studies were arranged at Yangzhou,China during the 2017–2018 cotton growth seasons.Five planting densities(15000,25000,45000,60000 and 75000 plants per hectare)and the flower-removal treatment were imposed separately on Bt cotton cultivar Sikang3 to arrange different boll setting rates,and the boll setting rates and Bt toxin content were compared.Results: Higher boll setting rate together with lower Bt toxin contents in boll wall was observed under low planting density,whereas lower boll setting rate and higher Bt toxin contents were found under high planting density.Also,higher Bt protein concentration was associated with higher soluble protein content,glutamic-pyruvic transaminase(GPT),and glutamic oxaloacetate transaminase(GOT)activities,but lower amino acid content,and protease and peptidase activities.It was further confirmed that a higher boll setting rate with lower Bt protein content under flower-removal.Conclusions: This study demonstrated that the insecticidal efficacy of boll walls was significantly impacted by boll formation.Reduced protein synthesis and enhanced protein degradation were related to the reduced Bt toxin concentration.
基金The project supported by grants from the Science and Technology Development Fund of Macao,China(058/2009and 078/2011/A3)Research Committee,University of Macao〔MYRG138(Y1-Y4)-ICMS12-LMY and MYRG139(Y1-Y4)-ICMS-LMY〕
文摘OBJECTIVE To analyze the whole transcriptome of zoanthid Protopalythoa variabilis(P.variabilis),a cnidarian,and discover the potential toxic substances in P.variabilis.METHODS The P.variabilis RNA deep sequencing was performed using the HiSeq 2500 automatic sequencing platform.All the unigenes generated from the assembly process were functionally annotated based on the similarity with databases.The multiple alignments of translated toxin-related sequences were performed with Clustalw2,and amino acid identity and similarity highlighted by using BoxShade tool.Three different methods including ITASSER,PEP-FOLD and MODELLER were applied to predict tri-dimensional models of toxin-related polypeptides from translated transcript sequences of P.variabilis.The toxicity of one of the putative toxins,namely ShK/Aurelin-like peptide,was evaluated using zebrafish model.RESULTS A total of 67,549,914 pairs of quality-filtered,90-base-pair Illumina reads from an mRNA sample were obtained.The de novo assemblies yielded 276,526 contigs.The sequence comparison of 130,121 unigenes with entries in Toxin database showed that 1542 unigenes were potential peptide toxins at which 11 unigenes were related to Stichodactyla toxin(ShK)domain(Pfam ID:PF01549).ShK is a 35 residues peptide sequence that was firstly discovered from the sea anemone Stichodactyla helianthus.Here,we found out one ShK-like peptide that processed a relatively higher sequence similarity with known ShK(Uniprot ID:P29186)of Bunodosoma granuliferum(red warty sea anemone).The Protopalythoa Shk-like peptide was submitted to Probis server to detect probable binding site and found to match with a protein AURELIN(PDB id:2lg4,UniProt id:Q0MWV8)which possesses structural homology with previously identified antimicrobial peptides and K+-channel-blocking toxins.Our results showed that the ShK/Aurelin-like peptide was lethal to zebrafish embryos at concentrations above 30-μmol·L1,and could induce zebrafish locomotor deficit at 10μmol·L-1.CONCLUSION This study,for the first time,presented the whole transcriptome profile and a potential toxic peptide of P.variabilis.
文摘Bacillus thuringiensis is a ubiquitous gram-positive, spore-forming bacterium that forms parasporal crystal during the stationary phase of its growth cycle. These crystal proteins, including Cry and Cyt protein, are toxic to certain insects. Lately, some problems about Cyt classification, structural characteristic, action mechanism and resistance to Cyt toxin are becoming new hotspots. We review the progress of above problems in several foreign labs.
基金Supported by the National Natural Science Foundation of China(31872530)。
文摘T-2 toxin is the most widespread mycotoxin in crops,feed and food,which poses a serious threat to body health.Bone is the main target tissue for T-2 toxin accumulation.Ingestion of food contaminated by T-2 toxin is the main cause of Kashin-Beck disease.However,the specific mechanism of bone damage caused by T-2 toxin is still unclear.In this study,a total of 40 male C57BL/6N mice were divided into four groups and orally treated with 0,0.5,1.0 and 2.0 mg·kg^(-1) body weight T-2 toxin for 28 days.The results showed that exposure to T-2 toxin led to weight loss,bone mineral density reduction and femoral structural damage of mice.In addition,osteoblast-mediated bone formation was inhibited,and osteoclast-mediated bone resorption was enhanced.Meanwhile,the levels of bone metabolism-related hormones including parathyroid hormone,calcitonin and 1,25-dihydroxyvitamin D3 were reduced.More importantly,it was found that the level of neuropeptide Y(a neurohormone)was decreased.These results provided a new perspetive for understanding the osteotoxicity of T-2 toxin.
