The Experts below are selected from a list of 60765 Experts worldwide ranked by ideXlab platform
Motomi Ito - One of the best experts on this subject based on the ideXlab platform.
-
gene expression profiling using cdna microarray analysis of the Sexual Reproduction stage of the unicellular charophycean alga closterium peracerosum strigosum littorale complex
Plant Physiology, 2006Co-Authors: Hiroyuki Sekimoto, Yuki Tsuchikane, Yoichi Tanabe, Hiroshi Shirosaki, Hiroo Fukuda, Taku Demura, Motomi ItoAbstract:The desmid Closterium peracerosum-strigosum-littorale complex, which is the closest unicellular sister to land plants, is the best characterized of the charophycean green algae with respect to the process of Sexual Reproduction. To elucidate the molecular mechanism of intercellular communication during Sexual Reproduction, we created a normalized cDNA library from mixed cells of the Sexual and the vegetative phases and generated a cDNA microarray. In total, 3,236 expressed sequence tags, which were classified into 1,615 nonredundant groups, were generated for cDNA microarray construction. Candidate genes for key factors involved in fertilization, such as those that encode putative receptor-like protein kinase, leucine-rich-repeat receptor-like protein, and sex pheromone homologs, were up-regulated during Sexual Reproduction and/or by the addition of the purified sex pheromones, and the expression patterns of these genes were confirmed by quantitative real-time polymerase chain reaction analysis. This first transcriptome profile of Closterium will provide critical clues as to the mechanism and evolution of intercellular communication between the egg and sperm cells of land plants.
-
expressed sequence tags from the closterium peracerosum strigosum littorale complex a unicellular charophycean alga in the Sexual Reproduction process
DNA Research, 2003Co-Authors: Hiroyuki Sekimoto, Yoichi Tanabe, Mari Takizawa, Nao Ito, Ryohei Fukumoto, Motomi ItoAbstract:We obtained genetic information on Sexual Reproduction of the Closterium peracerosum-strigosum-littorale complex, a unicellular charophycean alga. Normalized cDNA libraries were constructed from cells in the Sexual Reproduction process, and a total of 1190 5'-end expressed sequence tags were established. Since 604 of these ESTs were classified into 174 non-redundant sequences, these 1190 ESTs include 760 unique sequences. Similarity search against a public non-redundant protein database indicated that 390 unique sequences had significant similarity to registered sequences. Among these 390 sequences, 3 were identical to and 4 were homologous to previously identified sex-pheromone genes. According to our study, 370 of 760 unique sequences are likely to be novel transcripts. These cDNA clones and EST sequence information may would be helpful for future functional analyses using DNA array technologies.
Hiroyuki Sekimoto - One of the best experts on this subject based on the ideXlab platform.
-
Sexual Reproduction of a unicellular charophycean alga closterium peracerosum strogosum littorale complex
2014Co-Authors: Hiroyuki Sekimoto, Yuki Tsuchikane, Jun AbeAbstract:The genus Closterium is the best characterized charophycean green alga with respect to the process of Sexual Reproduction. Two sex pheromones , named PR-IP Inducer and PR-IP , that are involved in the progress of these processes were physiologically and biochemically characterized and the corresponding genes were cloned. These pheromones function in most steps of Sexual Reproduction. The timing after mixing, appropriate concentrations of the pheromones, and conditions of the cells are all essential for pheromones to be functional. To elucidate the molecular mechanisms of Sexual Reproduction in detail, molecular tools such as expressed sequence tag (EST), microarray analysis, and genetic transformation systems have been established. These methods will enable us to clarify the details of Sexual Reproduction in the near future.
-
gene expression profiling using cdna microarray analysis of the Sexual Reproduction stage of the unicellular charophycean alga closterium peracerosum strigosum littorale complex
Plant Physiology, 2006Co-Authors: Hiroyuki Sekimoto, Yuki Tsuchikane, Yoichi Tanabe, Hiroshi Shirosaki, Hiroo Fukuda, Taku Demura, Motomi ItoAbstract:The desmid Closterium peracerosum-strigosum-littorale complex, which is the closest unicellular sister to land plants, is the best characterized of the charophycean green algae with respect to the process of Sexual Reproduction. To elucidate the molecular mechanism of intercellular communication during Sexual Reproduction, we created a normalized cDNA library from mixed cells of the Sexual and the vegetative phases and generated a cDNA microarray. In total, 3,236 expressed sequence tags, which were classified into 1,615 nonredundant groups, were generated for cDNA microarray construction. Candidate genes for key factors involved in fertilization, such as those that encode putative receptor-like protein kinase, leucine-rich-repeat receptor-like protein, and sex pheromone homologs, were up-regulated during Sexual Reproduction and/or by the addition of the purified sex pheromones, and the expression patterns of these genes were confirmed by quantitative real-time polymerase chain reaction analysis. This first transcriptome profile of Closterium will provide critical clues as to the mechanism and evolution of intercellular communication between the egg and sperm cells of land plants.
-
expressed sequence tags from the closterium peracerosum strigosum littorale complex a unicellular charophycean alga in the Sexual Reproduction process
DNA Research, 2003Co-Authors: Hiroyuki Sekimoto, Yoichi Tanabe, Mari Takizawa, Nao Ito, Ryohei Fukumoto, Motomi ItoAbstract:We obtained genetic information on Sexual Reproduction of the Closterium peracerosum-strigosum-littorale complex, a unicellular charophycean alga. Normalized cDNA libraries were constructed from cells in the Sexual Reproduction process, and a total of 1190 5'-end expressed sequence tags were established. Since 604 of these ESTs were classified into 174 non-redundant sequences, these 1190 ESTs include 760 unique sequences. Similarity search against a public non-redundant protein database indicated that 390 unique sequences had significant similarity to registered sequences. Among these 390 sequences, 3 were identical to and 4 were homologous to previously identified sex-pheromone genes. According to our study, 370 of 760 unique sequences are likely to be novel transcripts. These cDNA clones and EST sequence information may would be helpful for future functional analyses using DNA array technologies.
Michael Schagerl - One of the best experts on this subject based on the ideXlab platform.
-
induction of Sexual Reproduction and zygospore patterns in the filamentous green alga spirogyra conjugatophyceae zygnematales
Journal of BioScience and Biotechnology, 2017Co-Authors: Mostafa M Elsheekh, Michael Schagerl, M M Gharieb, Ghada Abou ElsoudAbstract:Morphotaxonomy, ecological preferences and biological characterization of algal taxa of order Zygnematales (Conjugatophyceae, Chlorophyta), mainly the freshwater species Spirogyra, Zygnema, and Mougeotia are still poorly understood and need further in-depth investigations. In this study, different Spirogyra strains were examined to characterize their abilities in conjugation and formation of zygospores under different environmental conditions. It was found that 16:8-h light:dark photoperiod is the best condition to induce the conjugation and zygospore formation. Moreover, the Sexual Reproduction was noticed to be motivated with increasing the light intensity up to 85 µmol photons m-2s-1 and no conjugation was observed at 35 µmol photons m-2s-1. The attribute of conjugation in red and blue lights, respectively, never equalized that in the white light even with a high intensity. pH value (7.5) was the most suitable niche for induction of Sexual Reproduction in the studied Spirogyra strains. An increase of CO2 in the atmosphere, provided by NaHCO3 solution, did not enhance the Sexual Reproduction. Cultivation of the investigated Spirogyra strains on 0.003% CaCl2-containing agarized Pringhsheim´s medium (1/2 conc. and without nitrogen) induced the conjugation process as in case of CaCl2 omitted. UV radiation completely inhibited the conjugation at all growth conditions.
-
Induction of Sexual Reproduction and zygospore patterns in the filamentous green alga Spirogyra (Conjugatophyceae: Zygnematales)
Plovdiv University Press, 2017Co-Authors: Mostafa El-sheekh, Michael Schagerl, M M Gharieb, Ghada Abou ElsoudAbstract:Morphotaxonomy, ecological preferences and biological characterization of algal taxa of order Zygnematales (Conjugatophyceae, Chlorophyta), mainly the freshwater species Spirogyra, Zygnema, and Mougeotia are still poorly understood and need further in-depth investigations. In this study, different Spirogyra strains were examined to characterize their abilities in conjugation and formation of zygospores under different environmental conditions. We found that 16:8-h light:dark photoperiod is the best condition to induce the conjugation and zygospore formation. Moreover, the Sexual Reproduction was noticed to be triggered with increasing the light intensity to 85 μmol photons m-2s-1; no conjugation was observed at 35 μmol photons m-2s-1. The attribute of conjugation under red and blue irradiance, respectively, never equalized that in the white light even at elevated intensity. pH value (7.5) was the most suitable niche for induction of Sexual Reproduction. An increase of CO2 in the atmosphere, provided by NaHCO3 solution, did not enhance Sexual Reproduction. Cultivation of the investigated Spirogyra strains on 0.003% CaCl2-containing agarized Pringhsheim´s medium (1/2 conc. and without nitrogen) induced the conjugation process as in case of CaCl2 omitted. UV radiation completely inhibited the conjugation at all growth conditions
-
induction of Sexual Reproduction in spirogyra clones does an universal trigger exist
Fottea, 2013Co-Authors: Melanie Zwirn, Charlotte Chen, Bohuslav Uher, Michael SchagerlAbstract:Species identification of the ubiquitous green algae genus Spirogyra Link based on the traditional morphological species concept requires Sexual Reproduction stages including ripe hypnozygotes. Since these stages are only infrequently observed in nature, an artificial onset of the Sexual phase in the laboratory would be most welcome. We therefore tried to induce conjugation in 95 strains of Spirogyra originating from various European sampling localities. A linear discriminant analysis based on a comparison of abiotic field data between sites with vegetative and conjugating filaments indicated that nitrate deprivation together with elevated organic compounds of N and P promotes conjugation. In the laboratory, altogether 681 experimental setups were conducted with a focus on variation of nutrient supply and irradiance conditions. No general trigger could be found promoting Sexual Reproduction in the genus, but the importance of certain nutrient ratios according to specific ecological demands seems likely. Besides nitrate depletion, also red, green and white light sometimes yielded in Sexual Reproduction stages, whereas ultraviolet radiation and blue light never resulted in hypnozygote formation. Detailed mechanisms of recognition between the compatible filaments are still unknown; apomixis and/or heterothallism might be an explanation for the low success rate in sex induction.
Sandrine Gélisse - One of the best experts on this subject based on the ideXlab platform.
-
Sexual Reproduction in the Fungal Foliar Pathogen Zymoseptoria tritici Is Driven by Antagonistic Density Dependence Mechanisms
Microbial Ecology, 2019Co-Authors: Frederic Suffert, Ghislain Delestre, Sandrine GélisseAbstract:This study provides empirical evidence for antagonistic density dependence mechanisms driving Sexual Reproduction in the wheat fungal pathogen Zymoseptoria tritici. Biparental crosses with 12 increasing inoculum concentrations, in controlled conditions, showed that Sexual Reproduction in Z. tritici was impacted by an Allee effect due to mate limitation and a competition with aSexual multiplication for resource allocation. The highest number of ascospores discharged was reached at intermediate inoculum concentrations (from 5x10(4) conidiamL(-1) to 10(6) conidiamL(-1)). Consistent with these results for controlled co-inoculation, we found that the intensity of Sexual Reproduction varied with both cropping period and the vertical position of the host tissues in the field, with a maximum between 25 and 35cm above the ground. An optimal lesion density (disease severity of 30 to 45%) maximizing offspring (ascospores) number was established, and its eco-evolutionary consequences are considered here. Two ecological mechanisms may be involved: competition for resources between the two modes of Reproduction (decrease in the host resources available for Sexual Reproduction due to their prior use in aSexual multiplication), and competitive disequilibrium between the two parental isolates, due to differential interaction dynamics with the host, for example, leading to an imbalance between mating types. A conceptual model based on these results suggests that Sexual Reproduction plays a key role in the evolution of pathogenicity traits, including virulence and aggressiveness. Ecological knowledge about the determinants of Sexual Reproduction in Z. tritici may, therefore, open up new perspectives for the management of other fungal foliar pathogens with dual modes of Reproduction.
-
Sexual Reproduction in the fungal foliar pathogen zymoseptoria tritici is driven by antagonistic density dependence mechanisms
bioRxiv, 2018Co-Authors: Frederic Suffert, Ghislain Delestre, Sandrine GélisseAbstract:This study provides empirical evidence for antagonistic density-dependence mechanisms driving Sexual Reproduction in the wheat fungal pathogen Zymoseptoria tritici. Biparental crosses with 12 increasing inoculum concentrations, in controlled conditions, showed that Sexual Reproduction in Z. tritici was impacted by an Allee effect due to mate limitation and a competition with aSexual multiplication for resource allocation. We found that aSexual multiplication was itself affected by competition for host resources between the two parental isolates, as illustrated by the decrease in aSexual fruiting body density and sporulation intensity observed with increasing lesion density. Consistent with these results for controlled co-inoculation, we found that the intensity of Sexual Reproduction varied with both cropping period and the vertical position of the host tissues in the field. An optimal lesion density maximizing offspring (ascospores) number was established, and its eco-evolutionary consequences are considered here. Two ecological mechanisms may be involved: competition for resources between the two modes of Reproduction (decrease in the host resources available for Sexual Reproduction due to their prior use in aSexual multiplication), and competitive disequilibrium between the two parental isolates, due to differential interaction dynamics with the host, for example, leading to an imbalance between mating types. Conceptual models based on these results suggest that Sexual Reproduction plays a key role in the evolution of pathogenicity traits, including virulence and aggressiveness. Ecological knowledge about the determinants of Sexual Reproduction in Z. tritici may, therefore, open up new perspectives for the management of other fungal foliar pathogens with dual modes of Reproduction.
Yoichi Tanabe - One of the best experts on this subject based on the ideXlab platform.
-
gene expression profiling using cdna microarray analysis of the Sexual Reproduction stage of the unicellular charophycean alga closterium peracerosum strigosum littorale complex
Plant Physiology, 2006Co-Authors: Hiroyuki Sekimoto, Yuki Tsuchikane, Yoichi Tanabe, Hiroshi Shirosaki, Hiroo Fukuda, Taku Demura, Motomi ItoAbstract:The desmid Closterium peracerosum-strigosum-littorale complex, which is the closest unicellular sister to land plants, is the best characterized of the charophycean green algae with respect to the process of Sexual Reproduction. To elucidate the molecular mechanism of intercellular communication during Sexual Reproduction, we created a normalized cDNA library from mixed cells of the Sexual and the vegetative phases and generated a cDNA microarray. In total, 3,236 expressed sequence tags, which were classified into 1,615 nonredundant groups, were generated for cDNA microarray construction. Candidate genes for key factors involved in fertilization, such as those that encode putative receptor-like protein kinase, leucine-rich-repeat receptor-like protein, and sex pheromone homologs, were up-regulated during Sexual Reproduction and/or by the addition of the purified sex pheromones, and the expression patterns of these genes were confirmed by quantitative real-time polymerase chain reaction analysis. This first transcriptome profile of Closterium will provide critical clues as to the mechanism and evolution of intercellular communication between the egg and sperm cells of land plants.
-
expressed sequence tags from the closterium peracerosum strigosum littorale complex a unicellular charophycean alga in the Sexual Reproduction process
DNA Research, 2003Co-Authors: Hiroyuki Sekimoto, Yoichi Tanabe, Mari Takizawa, Nao Ito, Ryohei Fukumoto, Motomi ItoAbstract:We obtained genetic information on Sexual Reproduction of the Closterium peracerosum-strigosum-littorale complex, a unicellular charophycean alga. Normalized cDNA libraries were constructed from cells in the Sexual Reproduction process, and a total of 1190 5'-end expressed sequence tags were established. Since 604 of these ESTs were classified into 174 non-redundant sequences, these 1190 ESTs include 760 unique sequences. Similarity search against a public non-redundant protein database indicated that 390 unique sequences had significant similarity to registered sequences. Among these 390 sequences, 3 were identical to and 4 were homologous to previously identified sex-pheromone genes. According to our study, 370 of 760 unique sequences are likely to be novel transcripts. These cDNA clones and EST sequence information may would be helpful for future functional analyses using DNA array technologies.