The long-arm and short-arm genes of fibroin light chain (L-chain) of silkworm, Bombyx Mori L., and the gene of human acidic fibroblast growth factor were cloned respectively and subsequently inserted into a transfer v...The long-arm and short-arm genes of fibroin light chain (L-chain) of silkworm, Bombyx Mori L., and the gene of human acidic fibroblast growth factor were cloned respectively and subsequently inserted into a transfer vector pVL 1392 used as a tool to target the L-chain region of the silkworm genome. Genomic DNA from their offsprings was extracted and the expected targeting was detected using polymerase chain reaction and DNA sequencing, as well as protein analysis. The results showed that positive events occurred and that the FGF gene was integrated into the L-chain locus through homologous recombination.展开更多
Molecular systematic studies on mandarina silkworm (Bombyx mandarina M.) in 11 regions in China and 25 representative strains of domestic silkworm (Bombyx mori L.) were conducted using molecular biology techniques. Re...Molecular systematic studies on mandarina silkworm (Bombyx mandarina M.) in 11 regions in China and 25 representative strains of domestic silkworm (Bombyx mori L.) were conducted using molecular biology techniques. Results obtained from the analysis of DNA polymorphism and clustering of all the silkworm samples provide new evidence for the view that the domestic silkworm originated from the Chinese mandarina silkworm. On the basis of literature reviewing, a new hypothesis on the origin of the domestic silkworm was put forward. It was thought that the domestic silkworm was most probably domesticated from the Chinese mandarina silkworm of different ecotypes including monovoltinism, bivoltinism and multivoltinism; and that the domestic silkworm had the genetic background of monovoltinism, bivoltinism and multivoltinism at the very beginning of the domestication. The current strains of the domestic silkworm of different voltinism are the evolutionary results of thousands of years of rearing and artificial selections.展开更多
The posterior silk gland (PSG) of silkworm is an important organ where fibroin is synthesized and secreted exclusively. Because fibroin constitutes 75-80% of the silk filament, the mechanism governing fibroin secret...The posterior silk gland (PSG) of silkworm is an important organ where fibroin is synthesized and secreted exclusively. Because fibroin constitutes 75-80% of the silk filament, the mechanism governing fibroin secretion, quality and yield of cocoon can be elucidated by the study on the PSG. Using two-dimensional gel electrophoresis (2-DE) and image analysis system, the changes in the protein composition in the PSG cell were investigated on the day 1 (D1) and day 4 (D4) in the 5th instar stage from five different strains of silkworm (Bombyx mori). While differences at protein level between days and strains were far less than those observed at the gene level using EST analysis. The change trends in protein composition from D1 to D4 were diverse among the different strains. The results suggest that the secretion of fibroin is regulated by multiple proteins. The site of regulation and the proteins responsible for the regulation vary with the strain, which leads to differences between strains in the capacity of fibroin secretion in the PSG cell.展开更多
Two silkworm strains viz, B20 A (high cocoon shell ratio) and C. Nichi (low cocoon shell ratio) were sib mated for 10 generations to determine the homozygoeis. Both bulked segregant analysis (BSA) and near isogenic li...Two silkworm strains viz, B20 A (high cocoon shell ratio) and C. Nichi (low cocoon shell ratio) were sib mated for 10 generations to determine the homozygoeis. Both bulked segregant analysis (BSA) and near isogenic lines (NIL) studies were done to identify the RFLP markers doaely linked to cocoon shell parameters. Three hundred and fifty-two random clones were identified as the low copy number 'sequeiace and used for identification of Restriction Fragment Length Polyrnorphic (RFLP) marker linked to cocoon weight and cocoon shell character. In the bulk aegregant analysia, DNA from the parents (B20 A, C.Nichi), Fl and F2 progeny of high shell ratio (HSR) and low shell ratio (LSR) were screened for hybridization with the random clones. Polymorphic banding pattern achieved through southern hybridization with different probes indicated the probable correlation of polymorphism with high and low cocoon shell character which are possible landmarks in identifying the putative marker(s) for the cocoon shell character. Out of the 100 probes tried with parents, Fl, F2 and their bulks 10 probes were found to be closely linked to cocoon shell characters.展开更多
为探讨辛基酚对鳞翅目模式昆虫家蚕生长发育的影响,使用添加0.01~0.08 g·kg-1辛基酚(4-tert-octylphenol,4-t-OP)的人工饲料饲养家蚕(Bombyx mori L.),研究了4-t-OP对家蚕幼虫和蛹的生长发育速度、生长量、发育整齐度和生命力等影...为探讨辛基酚对鳞翅目模式昆虫家蚕生长发育的影响,使用添加0.01~0.08 g·kg-1辛基酚(4-tert-octylphenol,4-t-OP)的人工饲料饲养家蚕(Bombyx mori L.),研究了4-t-OP对家蚕幼虫和蛹的生长发育速度、生长量、发育整齐度和生命力等影响。结果表明:连续取食0.01 g·kg-1以上浓度4-t-OP的饲料,家蚕幼虫和蛹的生长发育速度(幼虫期和蛹期发育经过时间)、生长量(幼虫期体质量和蛹期茧层量)、生命力(3龄起蚕绝食生命时数、4龄起蚕结茧率、蚕茧的死笼率和羽化率)等都明显下降,抑制眠蚕体质量。4-t-OP对家蚕幼虫生长发育后期、化蛹及羽化等发育变态期的影响更加明显,其在家蚕体内可能有累积效应。添食0.08 g·kg-14-t-OP的家蚕不能完成生活史。研究表明,4-t-OP对家蚕生长发育毒性影响有显著的浓度效应和时间效应。展开更多
The economic importance of silkworm has moved biologists to explore various intricate mechanisms of the action of vertebrate hormones. The dietary administration of several vertebrate hormones and prostaglandins enhan...The economic importance of silkworm has moved biologists to explore various intricate mechanisms of the action of vertebrate hormones. The dietary administration of several vertebrate hormones and prostaglandins enhanced both developmental and metabolic processes of silkworm, Bombyx mori L. The main objective of sericulture research is to apply the results to achieve superior quality silk and greater output, to apply lab findings to achieve desirable ecenomic results.展开更多
This study reports the molecular detection of Bombyx mori nucleopolyhedrovirus (BmNPV) in silkworm strains of the Universidade Estadual de Maringá Brazilian Germplasm Bank (UBGB). DNA extraction was carried out b...This study reports the molecular detection of Bombyx mori nucleopolyhedrovirus (BmNPV) in silkworm strains of the Universidade Estadual de Maringá Brazilian Germplasm Bank (UBGB). DNA extraction was carried out by using six Bombyx mori female moths of each strain, followed by PCR amplification. A pair of primers was designed based on a specific sequence of the baculovirus genome related to the BmNPV ORF 14. Another pair of primers was used to amplify the silkworm Actin A3 gene segment, which was used as positive control. Twenty gene pools were analyzed, and fifteen revealed a fragment of 443 base pairs (bp), which indicated the presence of the BmNPV. The frequency of contaminated moths was as following: 100% for silkworm strains M18-2, M12-2 and J1;83% for C25, C75 and C24 strains;66% for KR01;50% for M11-A;33% for AS3, B106, M8 and M11 and 16% for C211, E8 and Hindu strains. These are promising results for the identification of contaminated B. mori moths by BmNPV, which may prevent virus proliferation in subsequent generations. We also analyzed DNA samples extracted from B. mori eggs, but the results were not conclusive regarding the detection of the fragments of the expected size (443 bp). The difficulty in detecting BmNPV contamination in B. mori eggs may be due to the low concentration of virus in samples.展开更多
Silkworm powder containing 1-deoxynojirimycin (DNJ) has α-glucosidase inhibitory activity and is promising as a complementary and alternative medicine (CAM) agent in Japan. Silkworm powder produced in Korea was extra...Silkworm powder containing 1-deoxynojirimycin (DNJ) has α-glucosidase inhibitory activity and is promising as a complementary and alternative medicine (CAM) agent in Japan. Silkworm powder produced in Korea was extracted with 75% ethanol. The extract was derivatized with 9-fluorenylmethyl chloroformate (FMOC-Cl), and DNJ-FMOC content was measured by HPLC. Then, alfa-glucosidase inhibition by silkworm and mulberry powder in pig liver crude enzyme was assayed using 4-nitrophenyl-alfa-D-glucopyranoside as a substrate. Silkworm powder DNJ content (0.39 to 0.58%) was higher than that in mulberry powder (0.08 to 0.12%). The alfa-glucosidase inhibitory activity of silkworm powder was more potent than that of mulberry leaves and green tea. Silkworm powder DNJ was stable upon heating to 121?C for up to 15 min.展开更多
Thirty-five SSR markers were used to construct 96 silkworm races fingerprint. All the SSR markers were polymorphic and unambiguously separated silkworm strains from each other. A total of 467 alleles were detected wit...Thirty-five SSR markers were used to construct 96 silkworm races fingerprint. All the SSR markers were polymorphic and unambiguously separated silkworm strains from each other. A total of 467 alleles were detected with a mean value of 13.34 alleles/locus (range 3-28). The mean polymorphism index content (PIC) was 0.71 (range 0.299-0.919). UPGMA cluster analysis of Nei's genetic distance grouped silkworm strains on the basis of their origin. The results indicated that SSR markers are efficient tools for fingerprinting cultivars and conducting genetic diversity studies in the silkworm.展开更多
基金Project supported by the ScientificResearch Foundation for
Returned Overseas Chinese Scholars,Education Ministry of Chinaand the Natural Science Foundation of Zhejiang Province (No.301306), China
文摘The long-arm and short-arm genes of fibroin light chain (L-chain) of silkworm, Bombyx Mori L., and the gene of human acidic fibroblast growth factor were cloned respectively and subsequently inserted into a transfer vector pVL 1392 used as a tool to target the L-chain region of the silkworm genome. Genomic DNA from their offsprings was extracted and the expected targeting was detected using polymerase chain reaction and DNA sequencing, as well as protein analysis. The results showed that positive events occurred and that the FGF gene was integrated into the L-chain locus through homologous recombination.
基金supported by the National Natural Science Foundation of China(No.39870603)the Special Funding Program of the Ministry of Education for Ph.D.Degree Awarding Units.
文摘Molecular systematic studies on mandarina silkworm (Bombyx mandarina M.) in 11 regions in China and 25 representative strains of domestic silkworm (Bombyx mori L.) were conducted using molecular biology techniques. Results obtained from the analysis of DNA polymorphism and clustering of all the silkworm samples provide new evidence for the view that the domestic silkworm originated from the Chinese mandarina silkworm. On the basis of literature reviewing, a new hypothesis on the origin of the domestic silkworm was put forward. It was thought that the domestic silkworm was most probably domesticated from the Chinese mandarina silkworm of different ecotypes including monovoltinism, bivoltinism and multivoltinism; and that the domestic silkworm had the genetic background of monovoltinism, bivoltinism and multivoltinism at the very beginning of the domestication. The current strains of the domestic silkworm of different voltinism are the evolutionary results of thousands of years of rearing and artificial selections.
文摘The posterior silk gland (PSG) of silkworm is an important organ where fibroin is synthesized and secreted exclusively. Because fibroin constitutes 75-80% of the silk filament, the mechanism governing fibroin secretion, quality and yield of cocoon can be elucidated by the study on the PSG. Using two-dimensional gel electrophoresis (2-DE) and image analysis system, the changes in the protein composition in the PSG cell were investigated on the day 1 (D1) and day 4 (D4) in the 5th instar stage from five different strains of silkworm (Bombyx mori). While differences at protein level between days and strains were far less than those observed at the gene level using EST analysis. The change trends in protein composition from D1 to D4 were diverse among the different strains. The results suggest that the secretion of fibroin is regulated by multiple proteins. The site of regulation and the proteins responsible for the regulation vary with the strain, which leads to differences between strains in the capacity of fibroin secretion in the PSG cell.
文摘Two silkworm strains viz, B20 A (high cocoon shell ratio) and C. Nichi (low cocoon shell ratio) were sib mated for 10 generations to determine the homozygoeis. Both bulked segregant analysis (BSA) and near isogenic lines (NIL) studies were done to identify the RFLP markers doaely linked to cocoon shell parameters. Three hundred and fifty-two random clones were identified as the low copy number 'sequeiace and used for identification of Restriction Fragment Length Polyrnorphic (RFLP) marker linked to cocoon weight and cocoon shell character. In the bulk aegregant analysia, DNA from the parents (B20 A, C.Nichi), Fl and F2 progeny of high shell ratio (HSR) and low shell ratio (LSR) were screened for hybridization with the random clones. Polymorphic banding pattern achieved through southern hybridization with different probes indicated the probable correlation of polymorphism with high and low cocoon shell character which are possible landmarks in identifying the putative marker(s) for the cocoon shell character. Out of the 100 probes tried with parents, Fl, F2 and their bulks 10 probes were found to be closely linked to cocoon shell characters.
文摘The economic importance of silkworm has moved biologists to explore various intricate mechanisms of the action of vertebrate hormones. The dietary administration of several vertebrate hormones and prostaglandins enhanced both developmental and metabolic processes of silkworm, Bombyx mori L. The main objective of sericulture research is to apply the results to achieve superior quality silk and greater output, to apply lab findings to achieve desirable ecenomic results.
基金supported by CAPES,CNPq,FINEP/Fundacao Araucaria and Secretaria de Estado da Ciencia,Tecnologia e Ensino Superior—FUNDO PARANA.
文摘This study reports the molecular detection of Bombyx mori nucleopolyhedrovirus (BmNPV) in silkworm strains of the Universidade Estadual de Maringá Brazilian Germplasm Bank (UBGB). DNA extraction was carried out by using six Bombyx mori female moths of each strain, followed by PCR amplification. A pair of primers was designed based on a specific sequence of the baculovirus genome related to the BmNPV ORF 14. Another pair of primers was used to amplify the silkworm Actin A3 gene segment, which was used as positive control. Twenty gene pools were analyzed, and fifteen revealed a fragment of 443 base pairs (bp), which indicated the presence of the BmNPV. The frequency of contaminated moths was as following: 100% for silkworm strains M18-2, M12-2 and J1;83% for C25, C75 and C24 strains;66% for KR01;50% for M11-A;33% for AS3, B106, M8 and M11 and 16% for C211, E8 and Hindu strains. These are promising results for the identification of contaminated B. mori moths by BmNPV, which may prevent virus proliferation in subsequent generations. We also analyzed DNA samples extracted from B. mori eggs, but the results were not conclusive regarding the detection of the fragments of the expected size (443 bp). The difficulty in detecting BmNPV contamination in B. mori eggs may be due to the low concentration of virus in samples.
文摘Silkworm powder containing 1-deoxynojirimycin (DNJ) has α-glucosidase inhibitory activity and is promising as a complementary and alternative medicine (CAM) agent in Japan. Silkworm powder produced in Korea was extracted with 75% ethanol. The extract was derivatized with 9-fluorenylmethyl chloroformate (FMOC-Cl), and DNJ-FMOC content was measured by HPLC. Then, alfa-glucosidase inhibition by silkworm and mulberry powder in pig liver crude enzyme was assayed using 4-nitrophenyl-alfa-D-glucopyranoside as a substrate. Silkworm powder DNJ content (0.39 to 0.58%) was higher than that in mulberry powder (0.08 to 0.12%). The alfa-glucosidase inhibitory activity of silkworm powder was more potent than that of mulberry leaves and green tea. Silkworm powder DNJ was stable upon heating to 121?C for up to 15 min.
文摘Thirty-five SSR markers were used to construct 96 silkworm races fingerprint. All the SSR markers were polymorphic and unambiguously separated silkworm strains from each other. A total of 467 alleles were detected with a mean value of 13.34 alleles/locus (range 3-28). The mean polymorphism index content (PIC) was 0.71 (range 0.299-0.919). UPGMA cluster analysis of Nei's genetic distance grouped silkworm strains on the basis of their origin. The results indicated that SSR markers are efficient tools for fingerprinting cultivars and conducting genetic diversity studies in the silkworm.