Fruit ripening is a complex process and is regulated by many factors. Ethylene and polygalacturonase （PG）, lipoxygenase （LOX）, expansin （EXP） are all critical regulating factors in fruit ripening and softening p...Fruit ripening is a complex process and is regulated by many factors. Ethylene and polygalacturonase （PG）, lipoxygenase （LOX）, expansin （EXP） are all critical regulating factors in fruit ripening and softening process. With antisense ACS tomato, Nr mutant tomato and cultivated tomato as materials, Northern blot hybridization showed that PG, LeEXP1 and LOXexpressed differently in different parts of cultivated tomato fruit during ripening, which was related to fruit ripening. The ripening process of columella and radial pericarp was faster than pericarp. In both Nr mutant and antisense ACS transgenic tomato fruit, expression levels ofPG, LeEXPI and LOXwere generally lower than those in cultivated fruit but still related to fruit ripening. The expression levels ofPG, LeEXP1 and LOX increased in the mature green tomato fruits after 0.5 h treatment with ethylene （100 μL/L）. These results indicate that gene expression ofPG, LeEXP1 and LOXwere positively regulated by ethylene. The time and cumulative effect of the concentration exists in the expression of PG regulated by ethylene. The regulation of LOX expression mainly depended on the fruit development after great amount of ethylene was produced. PG played a major role in ripening and softening of tomato fruit, and cooperated with the regulation of EXP and LOX.展开更多
We investigated the developmental expression pattern of AmphiCaM in cephalochordate amphioxus （Branchiostoma belcheri tsingtauense）. We cultured and sampled the animals at different developmental stages （eggs and l...We investigated the developmental expression pattern of AmphiCaM in cephalochordate amphioxus （Branchiostoma belcheri tsingtauense）. We cultured and sampled the animals at different developmental stages （eggs and larvae）, and used in-situ hybridization and northern blotting to document the spatial and temporal changes in AmphiCaM expression. The alimentary tract dominates the development from the late neurula stage to the adult stage. AmphiCaM expression increased significantly in the alimentary tract during the late neurula stage and remained elevated in the adults. Our results indicate that AmphiCaM is involved in the differentiation of the alimentary tract in amphioxus; and furthermore, provide an insight into the change in function of CaM genes during evolution.展开更多
The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length c DNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 219...The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length c DNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 2194 bp in length with a 981 bp open reading frame encoding 327 amino acids. With real-time PCR analysis, it was detected that Cf-sox2 was expressed in unfertilized oocytes, fertilized eggs and all the tested embryos and larvae. The expression level increased significantly(P < 0.01) in embryos from 2-cell to blastula, and then decreased significantly(P < 0.01) and reached the minimum in umbo larva. Moreover, location of the Cfsox2 expression was revealed using whole mount in situ hybridization technique. Positive hybridization signal could be detected in the central region of unfertilized oocytes and fertilized eggs, and then strong signals dispersed throughout the embryos from 2-cell to gastrula. During larval development, the signals were concentrated and strong signals were restricted to 4 regions of viscera mass in veliger larva. In umbo larva, weak signals could be detected in regions where presumptive visceral and pedal ganglia may be formed. The expression pattern of Cf-sox2 during embryogenesis was similar to that of mammal sox2, which implied that Cf-SOX2 may participate in the regulation of early development of C. farreri.展开更多
Nanopore has been developed to be a powerful,single-molecule analytical tool for sensing ions,small organic molecules and biomacromolecules such as proteins and DNAs.Generally,the identity of the analyte can be reveal...Nanopore has been developed to be a powerful,single-molecule analytical tool for sensing ions,small organic molecules and biomacromolecules such as proteins and DNAs.Generally,the identity of the analyte can be revealed by current amplitude changes and mean dwell time of the analyte binding events.In some cases,generation of highly characteristic current events affords an alternative way of analyte determination with high confidence level.However,we found that secondary structures in DNA/RNA hybrids might severely hinder the generation of signature events during their translocation through?-hemolysin nanopore.In this report,we propose a strategy to add a certain concentration of urea in the buffer solution for single channel recordings and validate that low concentration of urea can effectively denature the secondary structures in DNA hybrids and recover the generation of signature events.This finding might be useful in other secondary structure-related nanopore sensing activities.展开更多
基金Supported by National Project of Scientific and Technical Supporting Programs Funded by Ministry of Science and Technology of China (No.2006BAD22B01)National Natural Science Foundation of China (No.30800767)Postdoctoral Fund of China (No.20080430725)
文摘Fruit ripening is a complex process and is regulated by many factors. Ethylene and polygalacturonase （PG）, lipoxygenase （LOX）, expansin （EXP） are all critical regulating factors in fruit ripening and softening process. With antisense ACS tomato, Nr mutant tomato and cultivated tomato as materials, Northern blot hybridization showed that PG, LeEXP1 and LOXexpressed differently in different parts of cultivated tomato fruit during ripening, which was related to fruit ripening. The ripening process of columella and radial pericarp was faster than pericarp. In both Nr mutant and antisense ACS transgenic tomato fruit, expression levels ofPG, LeEXPI and LOXwere generally lower than those in cultivated fruit but still related to fruit ripening. The expression levels ofPG, LeEXP1 and LOX increased in the mature green tomato fruits after 0.5 h treatment with ethylene （100 μL/L）. These results indicate that gene expression ofPG, LeEXP1 and LOXwere positively regulated by ethylene. The time and cumulative effect of the concentration exists in the expression of PG regulated by ethylene. The regulation of LOX expression mainly depended on the fruit development after great amount of ethylene was produced. PG played a major role in ripening and softening of tomato fruit, and cooperated with the regulation of EXP and LOX.
基金Supported in part by Shandong Entry-Exit Inspection and Quarantine Bureau （SK200807） We thank Dr. LI Xiangning, who works in the CSR （Center for Scientific Review） of NIH （National Institutes of Health）, USA, for his critical reading of the manuscript.
文摘We investigated the developmental expression pattern of AmphiCaM in cephalochordate amphioxus （Branchiostoma belcheri tsingtauense）. We cultured and sampled the animals at different developmental stages （eggs and larvae）, and used in-situ hybridization and northern blotting to document the spatial and temporal changes in AmphiCaM expression. The alimentary tract dominates the development from the late neurula stage to the adult stage. AmphiCaM expression increased significantly in the alimentary tract during the late neurula stage and remained elevated in the adults. Our results indicate that AmphiCaM is involved in the differentiation of the alimentary tract in amphioxus; and furthermore, provide an insight into the change in function of CaM genes during evolution.
基金supported by the National High Technology Research and Development Program of China(863 Program)(2012AA10A402)
文摘The SOX2 protein is an important transcription factor functioning during the early development of animals. In this study, we isolated a full-length c DNA sequence of scallop Chlamys farreri sox2, Cf-sox2 which was 2194 bp in length with a 981 bp open reading frame encoding 327 amino acids. With real-time PCR analysis, it was detected that Cf-sox2 was expressed in unfertilized oocytes, fertilized eggs and all the tested embryos and larvae. The expression level increased significantly(P < 0.01) in embryos from 2-cell to blastula, and then decreased significantly(P < 0.01) and reached the minimum in umbo larva. Moreover, location of the Cfsox2 expression was revealed using whole mount in situ hybridization technique. Positive hybridization signal could be detected in the central region of unfertilized oocytes and fertilized eggs, and then strong signals dispersed throughout the embryos from 2-cell to gastrula. During larval development, the signals were concentrated and strong signals were restricted to 4 regions of viscera mass in veliger larva. In umbo larva, weak signals could be detected in regions where presumptive visceral and pedal ganglia may be formed. The expression pattern of Cf-sox2 during embryogenesis was similar to that of mammal sox2, which implied that Cf-SOX2 may participate in the regulation of early development of C. farreri.
基金the National Basic Research Program of China (2013CB932800)the National Natural Science Foundation of China (21175135, 21375130, 21205119, 21475132)the CAS Hundred Talents Program
文摘Nanopore has been developed to be a powerful,single-molecule analytical tool for sensing ions,small organic molecules and biomacromolecules such as proteins and DNAs.Generally,the identity of the analyte can be revealed by current amplitude changes and mean dwell time of the analyte binding events.In some cases,generation of highly characteristic current events affords an alternative way of analyte determination with high confidence level.However,we found that secondary structures in DNA/RNA hybrids might severely hinder the generation of signature events during their translocation through?-hemolysin nanopore.In this report,we propose a strategy to add a certain concentration of urea in the buffer solution for single channel recordings and validate that low concentration of urea can effectively denature the secondary structures in DNA hybrids and recover the generation of signature events.This finding might be useful in other secondary structure-related nanopore sensing activities.
