Somatic embryogenesis(SE) plays a vital role in genetic transformation and massive propagation of important agronomical and economical crops.Here,we conducted a systematic assessment of the morphological,cytochemical,...Somatic embryogenesis(SE) plays a vital role in genetic transformation and massive propagation of important agronomical and economical crops.Here,we conducted a systematic assessment of the morphological,cytochemical,and cytogenetical characteristics of six culture strains with various embryogenic/regenerative potential during SE process in cotton.Results indicated that the six cell culture strains had stable ploidy levels,and did not reveal any relationship between the cytogenetic state and their morphogenetic potential.Moreover,the six culture strains were compared via double staining with Evans blue and Acetocarmine to efficiently distinguish embryogenic and non-embryogenic cells and determine the embryogenic nature of the calli.In addition,the kind of auxins added in medium affected not only growth property,color,size of cell clumps but also ploidy level and regeneration ability.By combining analysis of morphological,cytochemical,and cytogenetical characteristics of the cell cultures,we are able to obtain and maintain homogeneous cell population with high morphogenic and regeneration ability and establish efficient somatic embryogenesis and regeneration system from short-term cell cultures in upland cotton,which highlight the application of biotechnological approaches in crop breeding,and above all,to better understand totipotency of cells in higher plants.展开更多
Cichoric acid is the main phenolic compound in the root and rhizome of the medicinal part, Echinacea purpurea that is known for possessing immune enhancing characteristics. In this study, we analysis the the synthesis...Cichoric acid is the main phenolic compound in the root and rhizome of the medicinal part, Echinacea purpurea that is known for possessing immune enhancing characteristics. In this study, we analysis the the synthesis and storage sites of phenolic compound in E. purpurea. We used fluorescent microscopy, transmission electron microscopy, cytochemical and immunocytochemical localization to observe the distribution of phenolic compounds. Our results show that the phenolic compounds were mostly distributed in the cortex parenchyma cells, vascular parenchyma cells and pith parenchyma cells in the root and rhizome, and mainly present in the vacuoles, large intercellular spaces and their surrounding cell walls. No phenolic compounds were observed in the cytoplasm and the organelles. We concluded that the phenolic compounds were synthetized in the cortex parenchyma cells, vascular parenchyma cells and pith parenchyma cells in the root and rhizome, and stored in the vacuoles of parenchyma cells. The above results provided significantly cytological information for further approaching the metabolic regulation and transfer pathways of phenolic compounds in biochemistry and molecular biology.展开更多
The effects of growth factors and calcium concentrations present in different culture media on induction of terminal differentiation were investigated for four different epidermoid carcinoma cell lines, Hela, KB, A431...The effects of growth factors and calcium concentrations present in different culture media on induction of terminal differentiation were investigated for four different epidermoid carcinoma cell lines, Hela, KB, A431, and SCC-25, and their responses determined relative to those elicited by normal human keratinocytes subjected to these culture conditions. Differentiation status was determined cyto-chemically by a validated keratin protein staining method, and by autoradiographic analyses. Growth and differentiation promoting factors that influenced the direction of integrated control of growth and differentiation in normal human keratinocytes were found to be effective for some cell lines but not others. The factors examined were 1) high density arrest in serum-free and serum-containing media, 2) media shifts from high density culture in serum-containing media to low density growth factor-depleted or supplemented serum-free medium, and 3) the concentration of calcium in the media. The extent and degree of differentiation achieved varied among different cell lines depend on the presence or absence of serum, EGF and insulin protein growth factors. Certain growth media appear to sponsor keratin protein, cyto-chemically-detected differentiation, and evidence of quantal mitotic division in low density HeLa cell and SCC25 cell cultures. Epidermoid carcinoma cell lines retain limited capacity to commit to early stages of cell differentiation.展开更多
Pea seedlings (Pisum sativum L.) were used as materials to test the timings and compartments of hydrogen peroxide (H2O2) triggered by wounding and exogenous jasmonic acid (JA). The results showed that H2O2 could be sy...Pea seedlings (Pisum sativum L.) were used as materials to test the timings and compartments of hydrogen peroxide (H2O2) triggered by wounding and exogenous jasmonic acid (JA). The results showed that H2O2 could be systemically induced by wounding and exogenous JA. H2O2 increased within 1 h and reached the peak 3―5 h after wounding in either the wounded leaves or the unwounded leaves adjacent to the wounded ones and the inferior leaves far from the wounded ones. After this, H2O2 decreased and recovered to the control level 12 h after wounding. The activities of antioxidant enzymes, however, were rapidly increased by wounding. Diphenylene iodonium (DPI), an inhibitor of NADPH oxidase, could significantly inhibit H2O2 burst that was mediated by wounding and exogenous JA. Assay of H2O2 subcellular location showed that H2O2 in response to wounding and exogenous JA was predominantly accumulated in plasma membrane, cell wall and apoplasmic space. Numerous JA (gold particles) was found via immu- nogold electron microscopy to be located in cell wall and phloem zones of mesophyll cell after wounding.展开更多
基金supported by the National Key R&D Program of China (2016YFD0100306)the National Natural Science Fundation of China (31401428)+1 种基金the Fok Ying-Tong Education Foundation of China (151024)the Taishan Scholar Talent Project from China (tsqn20161018)
文摘Somatic embryogenesis(SE) plays a vital role in genetic transformation and massive propagation of important agronomical and economical crops.Here,we conducted a systematic assessment of the morphological,cytochemical,and cytogenetical characteristics of six culture strains with various embryogenic/regenerative potential during SE process in cotton.Results indicated that the six cell culture strains had stable ploidy levels,and did not reveal any relationship between the cytogenetic state and their morphogenetic potential.Moreover,the six culture strains were compared via double staining with Evans blue and Acetocarmine to efficiently distinguish embryogenic and non-embryogenic cells and determine the embryogenic nature of the calli.In addition,the kind of auxins added in medium affected not only growth property,color,size of cell clumps but also ploidy level and regeneration ability.By combining analysis of morphological,cytochemical,and cytogenetical characteristics of the cell cultures,we are able to obtain and maintain homogeneous cell population with high morphogenic and regeneration ability and establish efficient somatic embryogenesis and regeneration system from short-term cell cultures in upland cotton,which highlight the application of biotechnological approaches in crop breeding,and above all,to better understand totipotency of cells in higher plants.
文摘Cichoric acid is the main phenolic compound in the root and rhizome of the medicinal part, Echinacea purpurea that is known for possessing immune enhancing characteristics. In this study, we analysis the the synthesis and storage sites of phenolic compound in E. purpurea. We used fluorescent microscopy, transmission electron microscopy, cytochemical and immunocytochemical localization to observe the distribution of phenolic compounds. Our results show that the phenolic compounds were mostly distributed in the cortex parenchyma cells, vascular parenchyma cells and pith parenchyma cells in the root and rhizome, and mainly present in the vacuoles, large intercellular spaces and their surrounding cell walls. No phenolic compounds were observed in the cytoplasm and the organelles. We concluded that the phenolic compounds were synthetized in the cortex parenchyma cells, vascular parenchyma cells and pith parenchyma cells in the root and rhizome, and stored in the vacuoles of parenchyma cells. The above results provided significantly cytological information for further approaching the metabolic regulation and transfer pathways of phenolic compounds in biochemistry and molecular biology.
文摘The effects of growth factors and calcium concentrations present in different culture media on induction of terminal differentiation were investigated for four different epidermoid carcinoma cell lines, Hela, KB, A431, and SCC-25, and their responses determined relative to those elicited by normal human keratinocytes subjected to these culture conditions. Differentiation status was determined cyto-chemically by a validated keratin protein staining method, and by autoradiographic analyses. Growth and differentiation promoting factors that influenced the direction of integrated control of growth and differentiation in normal human keratinocytes were found to be effective for some cell lines but not others. The factors examined were 1) high density arrest in serum-free and serum-containing media, 2) media shifts from high density culture in serum-containing media to low density growth factor-depleted or supplemented serum-free medium, and 3) the concentration of calcium in the media. The extent and degree of differentiation achieved varied among different cell lines depend on the presence or absence of serum, EGF and insulin protein growth factors. Certain growth media appear to sponsor keratin protein, cyto-chemically-detected differentiation, and evidence of quantal mitotic division in low density HeLa cell and SCC25 cell cultures. Epidermoid carcinoma cell lines retain limited capacity to commit to early stages of cell differentiation.
基金This work was supported by the National Natural Science Foundation of China(Grant No.30270918)the National High Technology Research and Development Program of China(863 ProgramGrant No.2003AA241170).
文摘Pea seedlings (Pisum sativum L.) were used as materials to test the timings and compartments of hydrogen peroxide (H2O2) triggered by wounding and exogenous jasmonic acid (JA). The results showed that H2O2 could be systemically induced by wounding and exogenous JA. H2O2 increased within 1 h and reached the peak 3―5 h after wounding in either the wounded leaves or the unwounded leaves adjacent to the wounded ones and the inferior leaves far from the wounded ones. After this, H2O2 decreased and recovered to the control level 12 h after wounding. The activities of antioxidant enzymes, however, were rapidly increased by wounding. Diphenylene iodonium (DPI), an inhibitor of NADPH oxidase, could significantly inhibit H2O2 burst that was mediated by wounding and exogenous JA. Assay of H2O2 subcellular location showed that H2O2 in response to wounding and exogenous JA was predominantly accumulated in plasma membrane, cell wall and apoplasmic space. Numerous JA (gold particles) was found via immu- nogold electron microscopy to be located in cell wall and phloem zones of mesophyll cell after wounding.
