The Experts below are selected from a list of 1887 Experts worldwide ranked by ideXlab platform
Pamela S. Soltis - One of the best experts on this subject based on the ideXlab platform.
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persea americana avocado bringing ancient flowers to fruit in the genomics era
BioEssays, 2008Co-Authors: Andre S Chanderbali, Douglas E Soltis, Victor A Albert, Vanessa E T M Ashworth, Michael T Clegg, Richard E Litz, Pamela S. SoltisAbstract:The avocado (Persea americana) is a major crop commodity worldwide. Moreover, avocado, a paleopolyploid, is an evolutionary "outpost" among flowering plants, representing a Basal lineage (the magnoliid clade) near the origin of the flowering plants themselves. Following centuries of selective breeding, avocado germplasm has been characterized at the level of microsatellite and RFLP markers. Nonetheless, little is known beyond these general diversity estimates, and much work remains to be done to develop avocado as a major subtropical-zone crop. Among the goals of avocado improvement are to develop varieties with fruit that will "store" better on the tree, show uniform ripening and have better post-harvest storage. Avocado transcriptome sequencing, genome mapping and partial genomic sequencing will represent a major step toward the goal of sequencing the entire avocado genome, which is expected to aid in improving avocado varieties and production, as well as understanding the evolution of flowers from non-flowering seed plants (gymnosperms). Additionally, continued evolutionary and other comparative studies of flower and fruit development in different avocado strains can be accomplished at the gene expression level, including in comparison with avocado relatives, and these should provide important insights into the genetic regulation of fruit development in Basal Angiosperms.
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Using plastid genome-scale data to resolve enigmatic relationships among Basal Angiosperms
Proceedings of the National Academy of Sciences of the United States of America, 2007Co-Authors: Michael J. Moore, Charles D. Bell, Pamela S. SoltisAbstract:Although great progress has been made in clarifying deep-level angiosperm relationships, several early nodes in the angiosperm branch of the Tree of Life have proved difficult to resolve. Perhaps the last great question remaining in Basal angiosperm phylogeny involves the branching order among the five major clades of mesAngiosperms (Ceratophyllum, Chloranthaceae, eudicots, magnoliids, and monocots). Previous analyses have found no consistent support for relationships among these clades. In an effort to resolve these relationships, we performed phylogenetic analyses of 61 plastid genes (≈42,000 bp) for 45 taxa, including members of all major Basal angiosperm lineages. We also report the complete plastid genome sequence of Ceratophyllum demersum. Parsimony analyses of combined and partitioned data sets varied in the placement of several taxa, particularly Ceratophyllum, whereas maximum-likelihood (ML) trees were more topologically stable. Total evidence ML analyses recovered a clade of Chloranthaceae + magnoliids as sister to a well supported clade of monocots + (Ceratophyllum + eudicots). ML bootstrap and Bayesian support values for these relationships were generally high, although approximately unbiased topology tests could not reject several alternative topologies. The extremely short branches separating these five lineages imply a rapid diversification estimated to have occurred between 143.8 ± 4.8 and 140.3 ± 4.8 Mya.
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the abc model and its applicability to Basal Angiosperms
Annals of Botany, 2007Co-Authors: Douglas E Soltis, Matyas Buzgo, Sangtae Kim, Andre S Chanderbali, Pamela S. SoltisAbstract:Background Although the flower is the central feature of the Angiosperms, little is known of its origin and subsequent diversification. The ABC model has long been the unifying paradigm for floral developmental genetics, but it is based on phylogenetically derived eudicot models. Synergistic research involving phylogenetics, classical developmental studies, genomics and developmental genetics has afforded valuable new insights into floral evolution in general, and the early flower in particular.
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expression of floral regulators in Basal Angiosperms and the origin and evolution of abc function
Advances in Botanical Research, 2006Co-Authors: Pamela S. Soltis, Matyas Buzgo, Douglas E Soltis, Sangtae Kim, Andre S ChanderbaliAbstract:Abstract The ABC‐model of floral organ identity explains the regular, sequential development of sepals, petals, stamens, and carpels in eudicot flowers. This general model, based on studies of the derived eudicots Arabidopsis and Antirrhinum, may apply to nearly all eudicots, most of which are characterized by discrete whorls of floral organs. However, floral morphology of Basal Angiosperms is typically characterized by variable numbers of floral parts and gradual transitions among floral organs, and it is unclear that the ABC‐model applies to such flowers. Here we explore the origin and evolution of ABC‐function through consideration of expression data for homologs of ABC‐genes for Basal Angiosperms and conclude that the ABC‐model represents an evolutionarily derived regulatory network that arose through spatial restriction of regulatory gene expression.
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Expression of floral MADS-box genes in Basal Angiosperms: implications for the evolution of floral regulators
Plant Journal, 2005Co-Authors: Hongzhi Kong, Hong Ma, Yi Hu, Pamela S. SoltisAbstract:*Summary The ABC model of floral organ identity is based on studies of Arabidopsis and Antirrhinum, both of which are highly derived eudicots. Most of the genes required for the ABC functions in Arabidopsis and Antirrhinum are members of the MADS-box gene family, and their orthologs are present in all major angiosperm lineages. Although the eudicots comprise 75% of all Angiosperms, most of the diversity in arrangement and number of floral parts is actually found among Basal angiosperm lineages, for which little is known about the genes that control floral development. To investigate the conservation and divergence of expression patterns of floral MADS-box genes in Basal Angiosperms relative to eudicot model systems, we isolated several floral MADS-box genes and examined their expression patterns in representative species, including Amborella (Amborellaceae), Nuphar (Nymphaeaceae) and Illicium (Austrobaileyales), the successive sister groups to all other extant Angiosperms, plus Magnolia and Asimina, members of the large magnoliid clade. Our results from multiple methods (relative-quantitative RT-PCR, real-time PCR and RNA in situ hybridization) revealed that expression patterns of floral MADS-box genes in Basal Angiosperms are broader than those of their counterparts in eudicots and monocots. In particular, (i) AP1 homologs are generally expressed in all floral organs and leaves, (ii) AP3/PI homologs are generally expressed in all floral organs and (iii) AG homologs are expressed in stamens and carpels of most Basal Angiosperms, in agreement with the expectations of the ABC model; however, an AG homolog is also expressed in the tepals of Illicium. The broader range of strong expression of AP3/PI homologs is inferred to be the ancestral pattern for all Angiosperms and is also consistent with the gradual morphological intergradations often observed between adjacent floral organs in Basal Angiosperms.
Matyas Buzgo - One of the best experts on this subject based on the ideXlab platform.
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an est database for liriodendron tulipifera l floral buds the first est resource for functional and comparative genomics in liriodendron
Tree Genetics & Genomes, 2008Co-Authors: Matyas Buzgo, Kerr P Wall, Lukas A. Mueller, Jim Leebensmack, John E Carlson, Haiying Liang, Lena LandherrAbstract:Liriodendron tulipifera L. was selected by the Floral Genome Project for identification of new genes related to floral diversity in Basal Angiosperms. A large, non-normalized cDNA library was constructed from premeiotic and meiotic floral buds and sequenced to generate a database of 9,531 high-quality expressed sequence tags. These sequences clustered into 6,520 unigenes, of which 5,251 were singletons, and 1,269 were in contigs. Homologs of genes regulating many aspects of flower development were identified, including those for organ identity and development, cell and tissue differentiation, and cell-cycle control. Almost 5% of the transcriptome consisted of homologs to known floral gene families. Homologs of most of the genes involved in cell-wall construction were also recovered. This provides a new opportunity for comparative studies in lignin biosynthesis, a trait of key importance in the evolution of land plants and in the utilization of fiber from economically important tree species, such as Liriodendron. Also of note is that 1,089 unigenes did not match any sequence in the public databases, including the complete genomes of Arabidopsis, rice, and Populus. Some of these novel genes might be unique in Basal angiosperm species and, when better characterized, may be informative for understanding the origins of diverged gene families. Thus, the Liriodendron expressed sequence tag database and library will help bridge our understanding of the mechanisms of flower initiation and development that are shared among Basal Angiosperms, eudicots, and monocots, and provide new opportunities for comparative analysis of gene families across angiosperm species.
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the abc model and its applicability to Basal Angiosperms
Annals of Botany, 2007Co-Authors: Douglas E Soltis, Matyas Buzgo, Sangtae Kim, Andre S Chanderbali, Pamela S. SoltisAbstract:Background Although the flower is the central feature of the Angiosperms, little is known of its origin and subsequent diversification. The ABC model has long been the unifying paradigm for floral developmental genetics, but it is based on phylogenetically derived eudicot models. Synergistic research involving phylogenetics, classical developmental studies, genomics and developmental genetics has afforded valuable new insights into floral evolution in general, and the early flower in particular.
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expression of floral regulators in Basal Angiosperms and the origin and evolution of abc function
Advances in Botanical Research, 2006Co-Authors: Pamela S. Soltis, Matyas Buzgo, Douglas E Soltis, Sangtae Kim, Andre S ChanderbaliAbstract:Abstract The ABC‐model of floral organ identity explains the regular, sequential development of sepals, petals, stamens, and carpels in eudicot flowers. This general model, based on studies of the derived eudicots Arabidopsis and Antirrhinum, may apply to nearly all eudicots, most of which are characterized by discrete whorls of floral organs. However, floral morphology of Basal Angiosperms is typically characterized by variable numbers of floral parts and gradual transitions among floral organs, and it is unclear that the ABC‐model applies to such flowers. Here we explore the origin and evolution of ABC‐function through consideration of expression data for homologs of ABC‐genes for Basal Angiosperms and conclude that the ABC‐model represents an evolutionarily derived regulatory network that arose through spatial restriction of regulatory gene expression.
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floral gene resources from Basal Angiosperms for comparative genomics research
BMC Plant Biology, 2005Co-Authors: Victor A Albert, Lena Landherr, Kerr P Wall, Lukas A. Mueller, John E Carlson, Douglas E Soltis, William G Farmerie, Daniel C Ilut, Teri M Solow, Matyas BuzgoAbstract:The Floral Genome Project was initiated to bridge the genomic gap between the most broadly studied plant model systems. Arabidopsis and rice, although now completely sequenced and under intensive comparative genomic investigation, are separated by at least 125 million years of evolutionary time, and cannot in isolation provide a comprehensive perspective on structural and functional aspects of flowering plant genome dynamics. Here we discuss new genomic resources available to the scientific community, comprising cDNA libraries and Expressed Sequence Tag (EST) sequences for a suite of phylogenetically Basal Angiosperms specifically selected to bridge the evolutionary gaps between model plants and provide insights into gene content and genome structure in the earliest flowering plants. Random sequencing of cDNAs from representatives of phylogenetically important eudicot, non-grass monocot, and gymnosperm lineages has so far (as of 12/1/04) generated 70,514 ESTs and 48,170 assembled unigenes. Efficient sorting of EST sequences into putative gene families based on whole Arabidopsis/rice proteome comparison has permitted ready identification of cDNA clones for finished sequencing. Preliminarily, (i) proportions of functional categories among sequenced floral genes seem representative of the entire Arabidopsis transcriptome, (ii) many known floral gene homologues have been captured, and (iii) phylogenetic analyses of ESTs are providing new insights into the process of gene family evolution in relation to the origin and diversification of the Angiosperms. Initial comparisons illustrate the utility of the EST data sets toward discovery of the basic floral transcriptome. These first findings also afford the opportunity to address a number of conspicuous evolutionary genomic questions, including reproductive organ transcriptome overlap between Angiosperms and gymnosperms, genome-wide duplication history, lineage-specific gene duplication and functional divergence, and analyses of adaptive molecular evolution. Since not all genes in the floral transcriptome will be associated with flowering, these EST resources will also be of interest to plant scientists working on other functions, such as photosynthesis, signal transduction, and metabolic pathways.
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floral developmental morphology of amborella trichopoda amborellaceae
International Journal of Plant Sciences, 2004Co-Authors: Matyas Buzgo, Pamela S. SoltisAbstract:We investigated the early floral development of the monotypic genus Amborella, the sister to all other extant Angiosperms. Examination of vegetative shoot development revealed that Amborella possesses both decussate and alternate phyllotaxy; one may simply be a special case of the other as a reaction to meristem size and shape. The transition from bracts to tepals is gradual, making it difficult to determine exactly where a flower begins in this species. Although flowers of Amborella are described as having spiral phyllotaxy, the periphery of the flower could be considered unidirectionally whorled. This new observation, together with observations of both spiral and whorled phyllotaxy in other Basal Angiosperms (e.g., Nuphar, Drimys, Ceratophyllum), further demonstrates the flexibility of floral development in Basal Angiosperms; i.e., some Basal Angiosperms are not fully committed to either spiral or whorled phyllotaxy. The developmental transitions between bracts and perianth, and between stamens and carp...
Kerr P Wall - One of the best experts on this subject based on the ideXlab platform.
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characterization of the Basal angiosperm aristolochia fimbriata a potential experimental system for genetic studies
BMC Plant Biology, 2013Co-Authors: Kerr P Wall, Stefan Wanke, Barbara J Bliss, Abdelali Barakat, Saravanaraj Ayyampalayam, Norman J Wickett, Yuannian JiaoAbstract:Previous studies in Basal Angiosperms have provided insight into the diversity within the angiosperm lineage and helped to polarize analyses of flowering plant evolution. However, there is still not an experimental system for genetic studies among Basal Angiosperms to facilitate comparative studies and functional investigation. It would be desirable to identify a Basal angiosperm experimental system that possesses many of the features found in existing plant model systems (e.g., Arabidopsis and Oryza). We have considered all Basal angiosperm families for general characteristics important for experimental systems, including availability to the scientific community, growth habit, and membership in a large Basal angiosperm group that displays a wide spectrum of phenotypic diversity. Most Basal Angiosperms are woody or aquatic, thus are not well-suited for large scale cultivation, and were excluded. We further investigated members of Aristolochiaceae for ease of culture, life cycle, genome size, and chromosome number. We demonstrated self-compatibility for Aristolochia elegans and A. fimbriata, and transformation with a GFP reporter construct for Saruma henryi and A. fimbriata. Furthermore, A. fimbriata was easily cultivated with a life cycle of just three months, could be regenerated in a tissue culture system, and had one of the smallest genomes among Basal Angiosperms. An extensive multi-tissue EST dataset was produced for A. fimbriata that includes over 3.8 million 454 sequence reads. Aristolochia fimbriata has numerous features that facilitate genetic studies and is suggested as a potential model system for use with a wide variety of technologies. Emerging genetic and genomic tools for A. fimbriata and closely related species can aid the investigation of floral biology, developmental genetics, biochemical pathways important in plant-insect interactions as well as human health, and various other features present in early Angiosperms.
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comparative transcriptomics among floral organs of the Basal eudicot eschscholzia californica as reference for floral evolutionary developmental studies
Genome Biology, 2010Co-Authors: Kerr P Wall, Laura M. Zahn, Qingqing Zhang, Naomi Altman, Donglan Tian, Cynthia J Gibas, Raad Z Gharaibeh, Jim LeebensmackAbstract:Molecular genetic studies of floral development have concentrated on several core eudicots and grasses (monocots), which have canalized floral forms. Basal eudicots possess a wider range of floral morphologies than the core eudicots and grasses and can serve as an evolutionary link between core eudicots and monocots, and provide a reference for studies of other Basal Angiosperms. Recent advances in genomics have enabled researchers to profile gene activities during floral development, primarily in the eudicot Arabidopsis thaliana and the monocots rice and maize. However, our understanding of floral developmental processes among the Basal eudicots remains limited. Using a recently generated expressed sequence tag (EST) set, we have designed an oligonucleotide microarray for the Basal eudicot Eschscholzia californica (California poppy). We performed microarray experiments with an interwoven-loop design in order to characterize the E. californica floral transcriptome and to identify differentially expressed genes in flower buds with pre-meiotic and meiotic cells, four floral organs at pre-anthesis stages (sepals, petals, stamens and carpels), developing fruits, and leaves. Our results provide a foundation for comparative gene expression studies between eudicots and Basal Angiosperms. We identified whorl-specific gene expression patterns in E. californica and examined the floral expression of several gene families. Interestingly, most E. californica homologs of Arabidopsis genes important for flower development, except for genes encoding MADS-box transcription factors, show different expression patterns between the two species. Our comparative transcriptomics study highlights the unique evolutionary position of E. californica compared with Basal Angiosperms and core eudicots.
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an est database for liriodendron tulipifera l floral buds the first est resource for functional and comparative genomics in liriodendron
Tree Genetics & Genomes, 2008Co-Authors: Matyas Buzgo, Kerr P Wall, Lukas A. Mueller, Jim Leebensmack, John E Carlson, Haiying Liang, Lena LandherrAbstract:Liriodendron tulipifera L. was selected by the Floral Genome Project for identification of new genes related to floral diversity in Basal Angiosperms. A large, non-normalized cDNA library was constructed from premeiotic and meiotic floral buds and sequenced to generate a database of 9,531 high-quality expressed sequence tags. These sequences clustered into 6,520 unigenes, of which 5,251 were singletons, and 1,269 were in contigs. Homologs of genes regulating many aspects of flower development were identified, including those for organ identity and development, cell and tissue differentiation, and cell-cycle control. Almost 5% of the transcriptome consisted of homologs to known floral gene families. Homologs of most of the genes involved in cell-wall construction were also recovered. This provides a new opportunity for comparative studies in lignin biosynthesis, a trait of key importance in the evolution of land plants and in the utilization of fiber from economically important tree species, such as Liriodendron. Also of note is that 1,089 unigenes did not match any sequence in the public databases, including the complete genomes of Arabidopsis, rice, and Populus. Some of these novel genes might be unique in Basal angiosperm species and, when better characterized, may be informative for understanding the origins of diverged gene families. Thus, the Liriodendron expressed sequence tag database and library will help bridge our understanding of the mechanisms of flower initiation and development that are shared among Basal Angiosperms, eudicots, and monocots, and provide new opportunities for comparative analysis of gene families across angiosperm species.
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floral gene resources from Basal Angiosperms for comparative genomics research
BMC Plant Biology, 2005Co-Authors: Victor A Albert, Lena Landherr, Kerr P Wall, Lukas A. Mueller, John E Carlson, Douglas E Soltis, William G Farmerie, Daniel C Ilut, Teri M Solow, Matyas BuzgoAbstract:The Floral Genome Project was initiated to bridge the genomic gap between the most broadly studied plant model systems. Arabidopsis and rice, although now completely sequenced and under intensive comparative genomic investigation, are separated by at least 125 million years of evolutionary time, and cannot in isolation provide a comprehensive perspective on structural and functional aspects of flowering plant genome dynamics. Here we discuss new genomic resources available to the scientific community, comprising cDNA libraries and Expressed Sequence Tag (EST) sequences for a suite of phylogenetically Basal Angiosperms specifically selected to bridge the evolutionary gaps between model plants and provide insights into gene content and genome structure in the earliest flowering plants. Random sequencing of cDNAs from representatives of phylogenetically important eudicot, non-grass monocot, and gymnosperm lineages has so far (as of 12/1/04) generated 70,514 ESTs and 48,170 assembled unigenes. Efficient sorting of EST sequences into putative gene families based on whole Arabidopsis/rice proteome comparison has permitted ready identification of cDNA clones for finished sequencing. Preliminarily, (i) proportions of functional categories among sequenced floral genes seem representative of the entire Arabidopsis transcriptome, (ii) many known floral gene homologues have been captured, and (iii) phylogenetic analyses of ESTs are providing new insights into the process of gene family evolution in relation to the origin and diversification of the Angiosperms. Initial comparisons illustrate the utility of the EST data sets toward discovery of the basic floral transcriptome. These first findings also afford the opportunity to address a number of conspicuous evolutionary genomic questions, including reproductive organ transcriptome overlap between Angiosperms and gymnosperms, genome-wide duplication history, lineage-specific gene duplication and functional divergence, and analyses of adaptive molecular evolution. Since not all genes in the floral transcriptome will be associated with flowering, these EST resources will also be of interest to plant scientists working on other functions, such as photosynthesis, signal transduction, and metabolic pathways.
Douglas E Soltis - One of the best experts on this subject based on the ideXlab platform.
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persea americana avocado bringing ancient flowers to fruit in the genomics era
BioEssays, 2008Co-Authors: Andre S Chanderbali, Douglas E Soltis, Victor A Albert, Vanessa E T M Ashworth, Michael T Clegg, Richard E Litz, Pamela S. SoltisAbstract:The avocado (Persea americana) is a major crop commodity worldwide. Moreover, avocado, a paleopolyploid, is an evolutionary "outpost" among flowering plants, representing a Basal lineage (the magnoliid clade) near the origin of the flowering plants themselves. Following centuries of selective breeding, avocado germplasm has been characterized at the level of microsatellite and RFLP markers. Nonetheless, little is known beyond these general diversity estimates, and much work remains to be done to develop avocado as a major subtropical-zone crop. Among the goals of avocado improvement are to develop varieties with fruit that will "store" better on the tree, show uniform ripening and have better post-harvest storage. Avocado transcriptome sequencing, genome mapping and partial genomic sequencing will represent a major step toward the goal of sequencing the entire avocado genome, which is expected to aid in improving avocado varieties and production, as well as understanding the evolution of flowers from non-flowering seed plants (gymnosperms). Additionally, continued evolutionary and other comparative studies of flower and fruit development in different avocado strains can be accomplished at the gene expression level, including in comparison with avocado relatives, and these should provide important insights into the genetic regulation of fruit development in Basal Angiosperms.
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the abc model and its applicability to Basal Angiosperms
Annals of Botany, 2007Co-Authors: Douglas E Soltis, Matyas Buzgo, Sangtae Kim, Andre S Chanderbali, Pamela S. SoltisAbstract:Background Although the flower is the central feature of the Angiosperms, little is known of its origin and subsequent diversification. The ABC model has long been the unifying paradigm for floral developmental genetics, but it is based on phylogenetically derived eudicot models. Synergistic research involving phylogenetics, classical developmental studies, genomics and developmental genetics has afforded valuable new insights into floral evolution in general, and the early flower in particular.
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expression of floral regulators in Basal Angiosperms and the origin and evolution of abc function
Advances in Botanical Research, 2006Co-Authors: Pamela S. Soltis, Matyas Buzgo, Douglas E Soltis, Sangtae Kim, Andre S ChanderbaliAbstract:Abstract The ABC‐model of floral organ identity explains the regular, sequential development of sepals, petals, stamens, and carpels in eudicot flowers. This general model, based on studies of the derived eudicots Arabidopsis and Antirrhinum, may apply to nearly all eudicots, most of which are characterized by discrete whorls of floral organs. However, floral morphology of Basal Angiosperms is typically characterized by variable numbers of floral parts and gradual transitions among floral organs, and it is unclear that the ABC‐model applies to such flowers. Here we explore the origin and evolution of ABC‐function through consideration of expression data for homologs of ABC‐genes for Basal Angiosperms and conclude that the ABC‐model represents an evolutionarily derived regulatory network that arose through spatial restriction of regulatory gene expression.
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floral gene resources from Basal Angiosperms for comparative genomics research
BMC Plant Biology, 2005Co-Authors: Victor A Albert, Lena Landherr, Kerr P Wall, Lukas A. Mueller, John E Carlson, Douglas E Soltis, William G Farmerie, Daniel C Ilut, Teri M Solow, Matyas BuzgoAbstract:The Floral Genome Project was initiated to bridge the genomic gap between the most broadly studied plant model systems. Arabidopsis and rice, although now completely sequenced and under intensive comparative genomic investigation, are separated by at least 125 million years of evolutionary time, and cannot in isolation provide a comprehensive perspective on structural and functional aspects of flowering plant genome dynamics. Here we discuss new genomic resources available to the scientific community, comprising cDNA libraries and Expressed Sequence Tag (EST) sequences for a suite of phylogenetically Basal Angiosperms specifically selected to bridge the evolutionary gaps between model plants and provide insights into gene content and genome structure in the earliest flowering plants. Random sequencing of cDNAs from representatives of phylogenetically important eudicot, non-grass monocot, and gymnosperm lineages has so far (as of 12/1/04) generated 70,514 ESTs and 48,170 assembled unigenes. Efficient sorting of EST sequences into putative gene families based on whole Arabidopsis/rice proteome comparison has permitted ready identification of cDNA clones for finished sequencing. Preliminarily, (i) proportions of functional categories among sequenced floral genes seem representative of the entire Arabidopsis transcriptome, (ii) many known floral gene homologues have been captured, and (iii) phylogenetic analyses of ESTs are providing new insights into the process of gene family evolution in relation to the origin and diversification of the Angiosperms. Initial comparisons illustrate the utility of the EST data sets toward discovery of the basic floral transcriptome. These first findings also afford the opportunity to address a number of conspicuous evolutionary genomic questions, including reproductive organ transcriptome overlap between Angiosperms and gymnosperms, genome-wide duplication history, lineage-specific gene duplication and functional divergence, and analyses of adaptive molecular evolution. Since not all genes in the floral transcriptome will be associated with flowering, these EST resources will also be of interest to plant scientists working on other functions, such as photosynthesis, signal transduction, and metabolic pathways.
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evolution of floral structures in Basal Angiosperms
International Journal of Plant Sciences, 2003Co-Authors: Louis Ronse P De Craene, Pamela S. Soltis, Douglas E SoltisAbstract:The evolution of selected characters of the perianth, androecium, and gynoecium was reconstructed on a modification of the recent three‐gene topology for Angiosperms to address patterns of evolution in the flowers of Basal Angiosperms. The reconstructions indicate that the patterns of perianth and stamen phyllotaxis are usually, but not always, closely associated. The attainment of a stable perianth and stamen phyllotaxis preceded stability in the gynoecium. There are several surprising reversals from whorled to spiral phyllotaxis in different clades. The developmental mechanisms responsible for changes in stamen number have rarely been evaluated in Basal Angiosperms, in contrast to the eudicots. Our reconstructions reveal a close relationship between a whorled phyllotaxis, a reduction of the number of stamen whorls, and stamens in double (paired) positions. Staminodes appear frequently in different lineages. A strict distinction between a sepal‐derived and a staminodial, stamen‐derived perianth is not al...
Barbara J Bliss - One of the best experts on this subject based on the ideXlab platform.
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characterization of the Basal angiosperm aristolochia fimbriata a potential experimental system for genetic studies
BMC Plant Biology, 2013Co-Authors: Kerr P Wall, Stefan Wanke, Barbara J Bliss, Abdelali Barakat, Saravanaraj Ayyampalayam, Norman J Wickett, Yuannian JiaoAbstract:Previous studies in Basal Angiosperms have provided insight into the diversity within the angiosperm lineage and helped to polarize analyses of flowering plant evolution. However, there is still not an experimental system for genetic studies among Basal Angiosperms to facilitate comparative studies and functional investigation. It would be desirable to identify a Basal angiosperm experimental system that possesses many of the features found in existing plant model systems (e.g., Arabidopsis and Oryza). We have considered all Basal angiosperm families for general characteristics important for experimental systems, including availability to the scientific community, growth habit, and membership in a large Basal angiosperm group that displays a wide spectrum of phenotypic diversity. Most Basal Angiosperms are woody or aquatic, thus are not well-suited for large scale cultivation, and were excluded. We further investigated members of Aristolochiaceae for ease of culture, life cycle, genome size, and chromosome number. We demonstrated self-compatibility for Aristolochia elegans and A. fimbriata, and transformation with a GFP reporter construct for Saruma henryi and A. fimbriata. Furthermore, A. fimbriata was easily cultivated with a life cycle of just three months, could be regenerated in a tissue culture system, and had one of the smallest genomes among Basal Angiosperms. An extensive multi-tissue EST dataset was produced for A. fimbriata that includes over 3.8 million 454 sequence reads. Aristolochia fimbriata has numerous features that facilitate genetic studies and is suggested as a potential model system for use with a wide variety of technologies. Emerging genetic and genomic tools for A. fimbriata and closely related species can aid the investigation of floral biology, developmental genetics, biochemical pathways important in plant-insect interactions as well as human health, and various other features present in early Angiosperms.
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Regeneration and plantlet development from somatic tissues of Aristolochia fimbriata
Plant Cell Tissue and Organ Culture (PCTOC), 2009Co-Authors: Barbara J Bliss, Lena Landherr, Claude W. Depamphilis, Siela N. MaximovaAbstract:Aristolochia fimbriata is a small herbaceous perennial in the Basal angiosperm family Aristolochiaceae. The family contains diverse floral forms ranging from radial to monosymmetric flowers with a wide variety of insect pollinators. Additionally, Aristolochia species contain secondary metabolites that are important natural toxins and traditional medicines, and are critical to the reproduction of swallowtail butterflies. These characteristics, in combination with the small genome size and short life cycle of A. fimbriata, have prompted further development of this species as a model system to study the evolution of Basal Angiosperms. As a prerequisite for developing a genetic transformation procedure for Aristolochia, we developed protocols for in vitro plant multiplication, shoot organogenesis, rooting, and acclimation of tissue culture-derived plants. Two varieties of Aristolochia were multiplied in vitro and rooted with 100% efficiency. Shoot regeneration was achieved within 1 month of culture initiation from whole leaf, internodal stem, and petiole explants. The highest regeneration success (97%) was recorded for stem explants. Regenerated and rooted shoots were acclimated to greenhouse conditions and developed flowers within 4 weeks of transplanting.
