[Objectives]In order to clarify the regulatory effects of insect hormones on the expression of BmSuc1 and provide a reference for further analysis of the function and expression regulation mechanism of BmSuc1,this stu...[Objectives]In order to clarify the regulatory effects of insect hormones on the expression of BmSuc1 and provide a reference for further analysis of the function and expression regulation mechanism of BmSuc1,this study explored the expression profiles of BmSuc1 in different tissues and periods of silkworm larvae and the expression changes of BmSuc1 after treatment with exogenous hormones.[Methods]By using the real-time fluorescence quantitative PCR technique,the expression characteristics of BmSuc1 were detected in different periods,different tissues and after treatment with exogenous hormones during the development of silkworm larvae.The expression of BmSuc1 and 20E receptor gene USP was detected after RNA interference with double-stranded RNA(dsRNA)of USP.[Results]The relative expression of BmSuc1 gene in the midgut was the highest,followed by the silk glands,epidermis and hemolymph.However,there was much lower or almost no expression in other tissues.In addition,the BmSuc1 expression profile exhibited a pulse-like pattern in silkworm larvae.The expression level of BmSuc1 was higher at each instar stage before molting,late fifth instar before cocooning and prepupal stage.Silkworm larvae at day 2 of the fifth instar were treated with 20-hydroxyecdysone(20E)and juvenile hormone(JH).It was found that the expression of BmSuc1 was extremely significantly higher at 12 and 18 h after 20E treatment than the control group injected with 0.1%dimethyl sulfoxide(DMSO)(P<0.01,the same below).But there were no significant difference in BmSuc1 expression between the JH treatment and the control group during the measurement time range(P>0.05).The dsRNA of USP was synthesized in vitro and injected into silkworm larvae at day 3 of the fifth instar.It was showed that the USP relative expression was extremely significantly down-regulated at 24 and 36 h after injection,which indicated that dsRNA interference was successful.RNAi of USP would block 20E signal transduction,and the expression of BmSuc1 was inhibited and significantly down-regulated at 24 and 36 h after injection of dsRNA of USP(P<0.05).[Conclusions]The BmSuc1 expression peaks appeared in the molting of silkworm larvae and the metamorphosis of larvae to pupae,which suggests that BmSuc1 may be involved in the metamorphic development process of silkworms.Treatment with exogenous ecdysone 20E can activate the expression of BmSuc1,but blocking the 20E signal transduction pathway may suppress expression of BmSuc1.It indicates that BmSuc1 as a downstream target gene in the 20E signal transduction pathway is directly or indirectly regulated by 20E signals.展开更多
In this study,silkworm strain T6,tolerant to fluoride,and silkworm strain 733xin,highly sensitive to fluoride,were used to construct the near-isogenic lines.300 random primers were used in RAPD amplification to DNAs o...In this study,silkworm strain T6,tolerant to fluoride,and silkworm strain 733xin,highly sensitive to fluoride,were used to construct the near-isogenic lines.300 random primers were used in RAPD amplification to DNAs of these lines.A molecular marker named S207 was found linked to the fluoride tolerance gene.Examination to F 2 segregated individuals of the above lines verified that this molecular marker was reliable.Subsequently,the molecular marker was cloned into a T vector (pUCm-T) for sequencing.Comparing with sequences available in the GenBank showed that this molecular marker was novel.We plan to convert it into a SCAR marker to facilitate establishment of a molecular marker assisted breeding system.展开更多
[Objective] The aim of this study was to investigate the efficient technique of artificial insemination for silkworm. [Method] Sperms were extracted from bursa copulatrix of female moths mated for 30 min through extru...[Objective] The aim of this study was to investigate the efficient technique of artificial insemination for silkworm. [Method] Sperms were extracted from bursa copulatrix of female moths mated for 30 min through extruding and centrifugal method, and then the semen was injected into other virgin moths with trypsinase. [ Result] A high-effective collection technology of spermatids from silkworm was established successfully, 50 μl semen could be collected by only one person in each hour. The survival rate of spermatids was over 80% in vito after collected from bursa copulatrix, while the obtained semen was quite pure and the average fertilization rate of silkworm was 76,5%. [ Conclusion] The establishment of high-effective semen extraction technique of silkworm provides the technical basis for studies on other related techniques for silkworm sperm.展开更多
[Objective] The aim was to investigate the expression level of recombinant gene P1-2A3C of FMDV Asia I in different Bombyx mori varieties,so as to screen out the B.mori varieties suitable for the foreign gene expressi...[Objective] The aim was to investigate the expression level of recombinant gene P1-2A3C of FMDV Asia I in different Bombyx mori varieties,so as to screen out the B.mori varieties suitable for the foreign gene expression.[Method] The recombinant B.mori baculovirus rBmNPV（P1-2A3C） are injected into pupae of original species and hybrids of B.mori respectively.Then,the expression of antigen is detected by ELISA method and compared.[Result] The expression level of P1-2A3C significantly differed in different B.mori varieties,in which,the hybrids of Qiufeng×TQ78 and Qiufeng×Sijiaojian could be considered as the effective bioreactors for high-level expression of foreign genes.[Conclusion] This study provided the basis for breeding special B.mori varieties which can highly express target protein of Asia I FMDV.展开更多
This paper summarized the diversity and prominent characteristics of naturally colored cocoon resources of Bombyx mori, and introduced the production methods of colored cocoons, the development and utilization of natu...This paper summarized the diversity and prominent characteristics of naturally colored cocoon resources of Bombyx mori, and introduced the production methods of colored cocoons, the development and utilization of naturally colored cocoon resources at home and abroad as well as the variety breeding instances, based on which suggestions were proposed for the development of colored cocoon industry.展开更多
[Objective] This study aimed to develop a new Bombyx mori variety Shuhuang No.1 and investigate its characteristics.[Method] The new variety was developed through cross breeding and pedigree separation.Its characteris...[Objective] This study aimed to develop a new Bombyx mori variety Shuhuang No.1 and investigate its characteristics.[Method] The new variety was developed through cross breeding and pedigree separation.Its characteristics were identified by laboratory tests and rural promotion practices in Sichuan Province.[Result]The cocoon produced by the new variety Shuhuang No.1 was golden-yellow and radiantly beautiful.Shuhuang No.1 was strong and easy to rear,uniform in development.The male and female ones could be distinguished by their larval color and markings.The cocoon yield per 10 000 the 4th instar larvae reached 20.30 kg; the length of a cocoon filament was about 1 115.0 m,and a non-broken filament was 882.95 mm long,accounting for 79.15％ of the total length.The raw silk ratio of fresh cocoon was 18.39％,and the neatness was 91.25 point.The main economic features of Shuhuang No.1 were better than those of the control.[Conclusion] The new variety had been approved by Sichuan Silkworm Evaluation Commission.It can be promoted in parent silkworm rearing areas Sichuan,Chongqing,Yangtze River basin.展开更多
基金Supported by The Special Agricultural Basic Cooperative Research Program of Yunnan Province(202301BD070001-229)Yunnan Fundamental Research Projects(202201AT070226)The Special Basic Cooperative Research Programs of Yunnan Provincial Undergraduate Universities Association(2021BA070001-070).
文摘[Objectives]In order to clarify the regulatory effects of insect hormones on the expression of BmSuc1 and provide a reference for further analysis of the function and expression regulation mechanism of BmSuc1,this study explored the expression profiles of BmSuc1 in different tissues and periods of silkworm larvae and the expression changes of BmSuc1 after treatment with exogenous hormones.[Methods]By using the real-time fluorescence quantitative PCR technique,the expression characteristics of BmSuc1 were detected in different periods,different tissues and after treatment with exogenous hormones during the development of silkworm larvae.The expression of BmSuc1 and 20E receptor gene USP was detected after RNA interference with double-stranded RNA(dsRNA)of USP.[Results]The relative expression of BmSuc1 gene in the midgut was the highest,followed by the silk glands,epidermis and hemolymph.However,there was much lower or almost no expression in other tissues.In addition,the BmSuc1 expression profile exhibited a pulse-like pattern in silkworm larvae.The expression level of BmSuc1 was higher at each instar stage before molting,late fifth instar before cocooning and prepupal stage.Silkworm larvae at day 2 of the fifth instar were treated with 20-hydroxyecdysone(20E)and juvenile hormone(JH).It was found that the expression of BmSuc1 was extremely significantly higher at 12 and 18 h after 20E treatment than the control group injected with 0.1%dimethyl sulfoxide(DMSO)(P<0.01,the same below).But there were no significant difference in BmSuc1 expression between the JH treatment and the control group during the measurement time range(P>0.05).The dsRNA of USP was synthesized in vitro and injected into silkworm larvae at day 3 of the fifth instar.It was showed that the USP relative expression was extremely significantly down-regulated at 24 and 36 h after injection,which indicated that dsRNA interference was successful.RNAi of USP would block 20E signal transduction,and the expression of BmSuc1 was inhibited and significantly down-regulated at 24 and 36 h after injection of dsRNA of USP(P<0.05).[Conclusions]The BmSuc1 expression peaks appeared in the molting of silkworm larvae and the metamorphosis of larvae to pupae,which suggests that BmSuc1 may be involved in the metamorphic development process of silkworms.Treatment with exogenous ecdysone 20E can activate the expression of BmSuc1,but blocking the 20E signal transduction pathway may suppress expression of BmSuc1.It indicates that BmSuc1 as a downstream target gene in the 20E signal transduction pathway is directly or indirectly regulated by 20E signals.
文摘In this study,silkworm strain T6,tolerant to fluoride,and silkworm strain 733xin,highly sensitive to fluoride,were used to construct the near-isogenic lines.300 random primers were used in RAPD amplification to DNAs of these lines.A molecular marker named S207 was found linked to the fluoride tolerance gene.Examination to F 2 segregated individuals of the above lines verified that this molecular marker was reliable.Subsequently,the molecular marker was cloned into a T vector (pUCm-T) for sequencing.Comparing with sequences available in the GenBank showed that this molecular marker was novel.We plan to convert it into a SCAR marker to facilitate establishment of a molecular marker assisted breeding system.
文摘[Objective] The aim of this study was to investigate the efficient technique of artificial insemination for silkworm. [Method] Sperms were extracted from bursa copulatrix of female moths mated for 30 min through extruding and centrifugal method, and then the semen was injected into other virgin moths with trypsinase. [ Result] A high-effective collection technology of spermatids from silkworm was established successfully, 50 μl semen could be collected by only one person in each hour. The survival rate of spermatids was over 80% in vito after collected from bursa copulatrix, while the obtained semen was quite pure and the average fertilization rate of silkworm was 76,5%. [ Conclusion] The establishment of high-effective semen extraction technique of silkworm provides the technical basis for studies on other related techniques for silkworm sperm.
基金Supported by863Project for Development and Production of New FMDV accine for Livestock(2011AA10A211)Fund for Agricultural Since and Technology Achievements Transformation(2009GB23260437)~~
文摘[Objective] The aim was to investigate the expression level of recombinant gene P1-2A3C of FMDV Asia I in different Bombyx mori varieties,so as to screen out the B.mori varieties suitable for the foreign gene expression.[Method] The recombinant B.mori baculovirus rBmNPV（P1-2A3C） are injected into pupae of original species and hybrids of B.mori respectively.Then,the expression of antigen is detected by ELISA method and compared.[Result] The expression level of P1-2A3C significantly differed in different B.mori varieties,in which,the hybrids of Qiufeng×TQ78 and Qiufeng×Sijiaojian could be considered as the effective bioreactors for high-level expression of foreign genes.[Conclusion] This study provided the basis for breeding special B.mori varieties which can highly express target protein of Asia I FMDV.
文摘This paper summarized the diversity and prominent characteristics of naturally colored cocoon resources of Bombyx mori, and introduced the production methods of colored cocoons, the development and utilization of naturally colored cocoon resources at home and abroad as well as the variety breeding instances, based on which suggestions were proposed for the development of colored cocoon industry.
文摘[Objective] This study aimed to develop a new Bombyx mori variety Shuhuang No.1 and investigate its characteristics.[Method] The new variety was developed through cross breeding and pedigree separation.Its characteristics were identified by laboratory tests and rural promotion practices in Sichuan Province.[Result]The cocoon produced by the new variety Shuhuang No.1 was golden-yellow and radiantly beautiful.Shuhuang No.1 was strong and easy to rear,uniform in development.The male and female ones could be distinguished by their larval color and markings.The cocoon yield per 10 000 the 4th instar larvae reached 20.30 kg; the length of a cocoon filament was about 1 115.0 m,and a non-broken filament was 882.95 mm long,accounting for 79.15％ of the total length.The raw silk ratio of fresh cocoon was 18.39％,and the neatness was 91.25 point.The main economic features of Shuhuang No.1 were better than those of the control.[Conclusion] The new variety had been approved by Sichuan Silkworm Evaluation Commission.It can be promoted in parent silkworm rearing areas Sichuan,Chongqing,Yangtze River basin.
