Angiosperms: Members of the group of vascular plants which bear flowers. They are differentiated from GYMNOSPERMS by their production of seeds within a closed chamber (OVARY, PLANT). The Angiosperms division is composed of two classes, the monocotyledons (Liliopsida) and dicotyledons (Magnoliopsida). Angiosperms represent approximately 80% of all known living plants.Gymnosperms: Gymnosperms are a group of vascular plants whose seeds are not enclosed by a ripened ovary (fruit), in contrast to ANGIOSPERMS whose seeds are surrounded by an ovary wall. The seeds of many gymnosperms (literally, "naked seed") are borne in cones and are not visible. Taxonomists now recognize four distinct divisions of extant gymnospermous plants (CONIFEROPHYTA; CYCADOPHYTA; GINKGOPHYTA; and GNETOPHYTA).Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Coniferophyta: A plant division of GYMNOSPERMS consisting of cone-bearing trees and shrubs.Flowers: The reproductive organs of plants.Genes, Plant: The functional hereditary units of PLANTS.Nymphaeaceae: The sour gum plant family of the order Nymphaeales, subclass Magnoliidae, class Magnoliopsida. All have horizontal or hanging branches and broad alternate leaves, and they are dioecious (male and female flowers on different plants).Genome, Plant: The genetic complement of a plant (PLANTS) as represented in its DNA.Evolution, Molecular: The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.DNA, Plant: Deoxyribonucleic acid that makes up the genetic material of plants.Ovule: The element in plants that contains the female GAMETOPHYTES.Nymphaea: A plant genus of the family NYMPHAEACEAE. The common name of lotus is also used for LOTUS and NELUMBO.Nuphar: A plant genus of the family NYMPHAEACEAE. Members contain sesquiterpene thioalkaloids.Biological Evolution: The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.Botany: The study of the origin, structure, development, growth, function, genetics, and reproduction of plants.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.DNA, Chloroplast: Deoxyribonucleic acid that makes up the genetic material of CHLOROPLASTS.Picea: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are evergreen, pyramidal trees with whorled branches and thin, scaly bark. Each of the linear, spirally arranged leaves is jointed near the stem on a separate woody base.Bryophyta: A division of the plant kingdom. Bryophyta contains the subdivision, Musci, which contains the classes: Andreaeopsida, BRYOPSIDA, and SPHAGNOPSIDA.Genome, Plastid: The genetic complement of PLASTIDS as represented in their DNA.Fossils: Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.Plants: Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.Selaginellaceae: A plant family of the order Selaginellales, class Lycopodiopsida, division Lycopodiophyta, subkingdom Tracheobionta. Members contain bilobetin. The rarely used common name of resurrection plant is mainly used with CRATEROSTIGMA.Ferns: Seedless nonflowering plants of the class Filicinae. They reproduce by spores that appear as dots on the underside of feathery fronds. In earlier classifications the Pteridophyta included the club mosses, horsetails, ferns, and various fossil groups. In more recent classifications, pteridophytes and spermatophytes (seed-bearing plants) are classified in the Subkingdom Tracheobionta (also known as Tracheophyta).Cycas: A plant genus of the family Cycadaceae, order Cycadales, class Cycadopsida, division CYCADOPHYTA of palm-like trees. It is a source of CYCASIN, the beta-D-glucoside of methylazoxymethanol.Alismatidae: A plant subclass of the class Liliopsida (monocotyledons) in the Chronquist classification system. This is equivalent to the Alismatales order in the APG classification system. It is a primitive group of more or less aquatic plants.Pollen: The fertilizing element of plants that contains the male GAMETOPHYTES.Annona: A plant genus of the family ANNONACEAE. It has edible fruit and seeds which contain acetogenins and benzoquinazoline and other alkaloids.Pollination: The transfer of POLLEN grains (male gametes) to the plant ovule (female gamete).Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.Plastids: Self-replicating cytoplasmic organelles of plant and algal cells that contain pigments and may synthesize and accumulate various substances. PLASTID GENOMES are used in phylogenetic studies.Seeds: The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.Trees: Woody, usually tall, perennial higher plants (Angiosperms, Gymnosperms, and some Pterophyta) having usually a main stem and numerous branches.Genome Size: The amount of DNA (or RNA) in one copy of a genome.Arabidopsis: A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.Pollen Tube: A growth from a pollen grain down into the flower style which allows two sperm to pass, one to the ovum within the ovule, and the other to the central cell of the ovule to produce endosperm of SEEDS.Liriodendron: A plant genus of the family MAGNOLIACEAE. Members include hardwood trees of eastern North America with distinct large tuliplike flowers.Geraniaceae: A plant family of the order Geraniales, subclass Rosidae, class Magnoliopsida.RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Bryopsida: A class of plants within the Bryophyta comprising the mosses, which are found in both damp (including freshwater) and drier situations. Mosses possess erect or prostrate leafless stems, which give rise to leafless stalks bearing capsules. Spores formed in the capsules are released and grow to produce new plants. (Concise Dictionary of Biology, 1990). Many small plants bearing the name moss are in fact not mosses. The "moss" found on the north side of trees is actually a green alga (CHLOROPHYTA). Irish moss is really a red alga (RHODOPHYTA). Beard lichen (beard moss), Iceland moss, oak moss, and reindeer moss are actually LICHENS. Spanish moss is a common name for both LICHENS and an air plant (TILLANDSIA usneoides) of the pineapple family. Club moss is an evergreen herb of the family LYCOPODIACEAE.Aristolochia: A plant genus of the family ARISTOLOCHIACEAE. Species of this genus have been used in traditional medicine but they contain aristolochic acid which is associated with nephropathy. These are sometimes called 'snakeroot' but that name is also used with a number of other plants such as POLYGALA; SANICULA; ASARUM; ARISTOLOCHIA; AGERATINA; and others.Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Germ Cells, Plant: The reproductive cells of plants.MADS Domain Proteins: A superfamily of proteins that share a highly conserved MADS domain sequence motif. The term MADS refers to the first four members which were MCM1 PROTEIN; AGAMOUS 1 PROTEIN; DEFICIENS PROTEIN; and SERUM RESPONSE FACTOR. Many MADS domain proteins have been found in species from all eukaryotic kingdoms. They play an important role in development, especially in plants where they have an important role in flower development.Gene Duplication: Processes occurring in various organisms by which new genes are copied. Gene duplication may result in a MULTIGENE FAMILY; supergenes or PSEUDOGENES.Embryophyta: Higher plants that live primarily in terrestrial habitats, although some are secondarily aquatic. Most obtain their energy from PHOTOSYNTHESIS. They comprise the vascular and non-vascular plants.Tracheobionta: A subset of various vascular plants (also known as the Tracheophyta) which include seed-bearing and non seed-bearing species.Chloroplasts: Plant cell inclusion bodies that contain the photosynthetic pigment CHLOROPHYLL, which is associated with the membrane of THYLAKOIDS. Chloroplasts occur in cells of leaves and young stems of plants. They are also found in some forms of PHYTOPLANKTON such as HAPTOPHYTA; DINOFLAGELLATES; DIATOMS; and CRYPTOPHYTA.Zamiaceae: A plant family of the order Cycadales, class Cycadopsida, division CYCADOPHYTA.Endosperm: Nutritive tissue of the seeds of flowering plants that surrounds the EMBRYOS. It is produced by a parallel process of fertilization in which a second male gamete from the pollen grain fuses with two female nuclei within the embryo sac. The endosperm varies in ploidy and contains reserves of starch, oils, and proteins, making it an important source of human nutrition.Hydrocharitaceae: A plant family of the order Hydrocharitales, subclass ALISMATIDAE, class Liliopsida (monocotyledons).Genome, Chloroplast: The genetic complement of CHLOROPLASTS as represented in their DNA.Biodiversity: The variety of all native living organisms and their various forms and interrelationships.Pinus: A plant genus in the family PINACEAE, order Pinales, class Pinopsida, division Coniferophyta. They are evergreen trees mainly in temperate climates.Araceae: A plant family of the order Arales, subclass Arecidae, class Liliopsida (monocot). Many members contain OXALIC ACID and calcium oxalate (OXALATES).Arabidopsis Proteins: Proteins that originate from plants species belonging to the genus ARABIDOPSIS. The most intensely studied species of Arabidopsis, Arabidopsis thaliana, is commonly used in laboratory experiments.Plant Shoots: New immature growth of a plant including stem, leaves, tips of branches, and SEEDLINGS.Pinus taeda: A plant species of the genus PINUS which is the subject of genetic study.Persea: A plant genus in the LAURACEAE family. The tree, Persea americana Mill., is known for the Avocado fruit, the food of commerce.Orobanche: A plant genus of the family OROBANCHACEAE. Lacking chlorophyll, they are nonphotosynthetic parasitic plants. The common name is similar to Broom or Scotch Broom (CYTISUS) or Butcher's Broom (RUSCUS) or Desert Broom (BACCHARIS) or Spanish Broom (SPARTIUM) or Brome (BROMUS).Orchidaceae: A plant family of the order Orchidales, subclass Liliidae, class Liliopsida (monocotyledons). All orchids have the same bilaterally symmetrical flower structure, with three sepals, but the flowers vary greatly in color and shape.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Malpighiaceae: A plant family of the order Polygalales, subclass Rosidae class, Magnoliopsida that are mostly shrubs and small trees. Many of the members contain indole alkaloids.Crassulaceae: The stonecrop plant family of the order ROSALES, subclass Rosidae, class Magnoliopsida that grow in warm, dry regions. The leaves are thick. The flower clusters are red, yellow, or white.Multigene Family: A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed)Oryza sativa: Annual cereal grass of the family POACEAE and its edible starchy grain, rice, which is the staple food of roughly one-half of the world's population.Lignin: The most abundant natural aromatic organic polymer found in all vascular plants. Lignin together with cellulose and hemicellulose are the major cell wall components of the fibers of all wood and grass species. Lignin is composed of coniferyl, p-coumaryl, and sinapyl alcohols in varying ratios in different plant species. (From Merck Index, 11th ed)Genome, Mitochondrial: The genetic complement of MITOCHONDRIA as represented in their DNA.Self-Fertilization: The fusion of a male gamete with a female gamete from the same individual animal or plant.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Plant Physiological Phenomena: The physiological processes, properties, and states characteristic of plants.Campanulaceae: A plant family of the order Campanulales, subclass Asteridae, class MagnoliopsidaSequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Genes, Mitochondrial: Genes that are located on the MITOCHONDRIAL DNA. Mitochondrial inheritance is often referred to as maternal inheritance but should be differentiated from maternal inheritance that is transmitted chromosomally.Flowering Tops: Tops of plants when in flower, including the stems, leaves and blooms.Polyploidy: The chromosomal constitution of a cell containing multiples of the normal number of CHROMOSOMES; includes triploidy (symbol: 3N), tetraploidy (symbol: 4N), etc.Meristem: A group of plant cells that are capable of dividing infinitely and whose main function is the production of new growth at the growing tip of a root or stem. (From Concise Dictionary of Biology, 1990)Reproduction: The total process by which organisms produce offspring. (Stedman, 25th ed)Viburnum: A plant genus in the family CAPRIFOLIACEAE. The common name derives from its traditional use for menstrual cramps. It is a source of viburnine, valerianic acid, vibsanin, and ursolic acid. Note that true cranberry is VACCINIUM MACROCARPON.Plant Stomata: Closable openings in the epidermis of plants on the underside of leaves. They allow the exchange of gases between the internal tissues of the plant and the outside atmosphere.Silene: A plant genus of the family CARYOPHYLLACEAE. The common name of campion is also used with LYCHNIS. The common name of 'pink' can be confused with other plants.Populus: A plant genus of the family SALICACEAE. Balm of Gilead is a common name used for P. candicans, or P. gileadensis, or P. jackii, and sometimes also used for ABIES BALSAMEA or for COMMIPHORA.Genetic Variation: Genotypic differences observed among individuals in a population.Tropical Climate: A climate which is typical of equatorial and tropical regions, i.e., one with continually high temperatures with considerable precipitation, at least during part of the year. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Plant Infertility: The failure of PLANTS to complete fertilization and obtain seed (SEEDS) as a result of defective POLLEN or ovules, or other aberrations. (Dict. of Plant Genet. and Mol. Biol., 1998)Plant Transpiration: The loss of water vapor by plants to the atmosphere. It occurs mainly from the leaves through pores (stomata) whose primary function is gas exchange. The water is replaced by a continuous column of water moving upwards from the roots within the xylem vessels. (Concise Dictionary of Biology, 1990)Nelumbo: A plant genus of the family NELUMBONACEAE. The common name of lotus is also for LOTUS and NYMPHAEA.Solanaceae: A plant family of the order Solanales, subclass Asteridae. Among the most important are POTATOES; TOMATOES; CAPSICUM (green and red peppers); TOBACCO; and BELLADONNA.Ecosystem: A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Chromosomes, Plant: Complex nucleoprotein structures which contain the genomic DNA and are part of the CELL NUCLEUS of PLANTS.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.RNA Editing: A process that changes the nucleotide sequence of mRNA from that of the DNA template encoding it. Some major classes of RNA editing are as follows: 1, the conversion of cytosine to uracil in mRNA; 2, the addition of variable number of guanines at pre-determined sites; and 3, the addition and deletion of uracils, templated by guide-RNAs (RNA, GUIDE).Hepatophyta: A plant division. They are simple plants that lack vascular tissue and possess rudimentary rootlike organs (rhizoids). Like MOSSES, liverworts have alternation of generations between haploid gamete-bearing forms (gametophytes) and diploid spore-bearing forms (sporophytes).Inflorescence: A cluster of FLOWERS (as opposed to a solitary flower) arranged on a main stem of a plant.Winteraceae: A plant family of the order Magnoliales, subclass Magnoliidae, class Magnoliopsida. The wood lacks water-conducting cells but has acrid sap. The leaves are gland-dotted, leathery, and smooth-margined. The flowers are small, in clusters, with two to six sepals, petals in two or more series, several stamens, and one to several carpels.Proteaceae: A plant family of the order Proteales, subclass Rosidae class Magnoliopsida. Cluster roots, bottlebrush-like clusters of rootlets which form in response to poor soil, are common in this family.Senecio: A species of toxic plants of the Compositae. The poisonous compounds are alkaloids which cause cattle diseases, neoplasms, and liver damage and are used to produce cancers in experimental animals.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Plant Structures: The parts of plants, including SEEDS.RNA, Ribosomal, 18S: Constituent of the 40S subunit of eukaryotic ribosomes. 18S rRNA is involved in the initiation of polypeptide synthesis in eukaryotes.Seedling: Very young plant after GERMINATION of SEEDS.Plant Roots: The usually underground portions of a plant that serve as support, store food, and through which water and mineral nutrients enter the plant. (From American Heritage Dictionary, 1982; Concise Dictionary of Biology, 1990)

Screening of Korean forest plants for rat lens aldose reductase inhibition. (1/1498)

Naturally occurring substances which can prevent and treat diabetic complications were sought by examining ethanol extracts prepared from Korean forest plants for their inhibitory effects on rat lens aldose reductase activity in vitro. Among the plants examined, Acer ginnala, Illicium religiosum and Cornus macrophylla exerted the most strong inhibitory activity on aldose reductase.  (+info)

Antioxidative and chelating activities of phenylpropanoid glycosides from Pedicularis striata. (2/1498)

AIM: To study the antioxidative and iron chelating activities of phenylpropanoid glycosides (PPG) isolated from a Chinese herb Pedicularis striata. METHODS: Antioxidative effects of PPG on lipid peroxidation induced by FeSO4-edetic acid in linoleic acid were measured by thiobarbituric acid method. Chelating activities of PPG for Fe2+ were tested by differential spectrum method. RESULTS: The reaction rates (A532.min-1) of lipid peroxidation were 0.0046 in the control, 0.0021 in verbascoside group, and 0.0008 in isoverbascoside group. The chelating activity of isoverbascoside was 2-fold stronger than that of verbascoside. Permethyl verbascoside showed neither antioxidative nor chelating activities. CONCLUSION: The inhibitory effects of PPG with phenolic hydroxy groups on lipid peroxidation are owing to their chelating properties. Under physiological condition PPG-Fe2+ chelates are sufficiently stable. Thus PPG are able to inhibit the Fe(2+)-dependent lipid peroxidation in vivo through chelating Fe2+ and exhibit their therapeutic potential by the same mechanism in vitro.  (+info)

Continuous primary sequence requirements in the 18-nucleotide promoter of dicot plant mitochondria. (3/1498)

The nucleotide requirements of mitochondrial promoters of dicot plants were studied in detail in a pea in vitro transcription system. Deletions in the 5' regions of three different transcription initiation sites from pea, soybean, and Oenothera identified a crucial AT-rich sequence element (AT-Box) comprising nucleotide positions -14 to -9 relative to the first transcribed nucleotide. Transversion of the AT-Box sequence to comple- mentary nucleotide identities results in an almost complete loss of promoter activity, suggesting that primary structure rather than a simple accumulation of adenines and thymidines in this region is essential for promoter activity. This promoter segment thus appears to be involved in sequence specific binding of a respective protein factor(s) rather than merely loosening and melting the DNA helix during or for an initiation event. Manipulation of nucleotide identities in the 3' portion of the pea atp9 promoter and the respective 3'-flanking region revealed that essential sequences extend to positions +3/+4 beyond this transcription start site. Efficient transcription initiation at an 18-base pair promoter sequence ranging from nucleotide positions -14 to +4 integrated into different sequence contexts shows this element to be sufficient for autonomous promoter function independent of surrounding sequences.  (+info)

Characterization of two novel type I ribosome-inactivating proteins from the storage roots of the andean crop Mirabilis expansa. (4/1498)

Two novel type I ribosome-inactivating proteins (RIPs) were found in the storage roots of Mirabilis expansa, an underutilized Andean root crop. The two RIPs, named ME1 and ME2, were purified to homogeneity by ammonium sulfate precipitation, cation-exchange perfusion chromatography, and C4 reverse-phase chromatography. The two proteins were found to be similar in size (27 and 27.5 kD) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their isoelectric points were determined to be greater than pH 10.0. Amino acid N-terminal sequencing revealed that both ME1 and ME2 had conserved residues characteristic of RIPs. Amino acid composition and western-blot analysis further suggested a structural similarity between ME1 and ME2. ME2 showed high similarity to the Mirabilis jalapa antiviral protein, a type I RIP. Depurination of yeast 26S rRNA by ME1 and ME2 demonstrated their ribosome-inactivating activity. Because these two proteins were isolated from roots, their antimicrobial activity was tested against root-rot microorganisms, among others. ME1 and ME2 were active against several fungi, including Pythium irregulare, Fusarium oxysporum solani, Alternaria solani, Trichoderma reesei, and Trichoderma harzianum, and an additive antifungal effect of ME1 and ME2 was observed. Antibacterial activity of both ME1 and ME2 was observed against Pseudomonas syringae, Agrobacterium tumefaciens, Agrobacterium radiobacter, and others.  (+info)

The prenylation status of a novel plant calmodulin directs plasma membrane or nuclear localization of the protein. (5/1498)

Post-translational attachment of isoprenyl groups to conserved cysteine residues at the C-terminus of a number of regulatory proteins is important for their function and subcellular localization. We have identified a novel calmodulin, CaM53, with an extended C-terminal basic domain and a CTIL CaaX-box motif which are required for efficient prenylation of the protein in vitro and in vivo. Ectopic expression of wild-type CaM53 or a non-prenylated mutant protein in plants causes distinct morphological changes. Prenylated CaM53 associates with the plasma membrane, but the non-prenylated mutant protein localizes to the nucleus, indicating a dual role for the C-terminal domain. The subcellular localization of CaM53 can be altered by a block in isoprenoid biosynthesis or sugar depletion, suggesting that CaM53 activates different targets in response to metabolic changes. Thus, prenylation of CaM53 appears to be a novel mechanism by which plant cells can coordinate Ca2+ signaling with changes in metabolic activities.  (+info)

Tissue-specific expression of the beta-subunit of tryptophan synthase in Camptotheca acuminata, an indole alkaloid-producing plant. (6/1498)

Camptothecin is an anticancer drug produced by the monoterpene indole alkaloid pathway in Camptotheca acuminata. As part of an investigation of the camptothecin biosynthetic pathway, we have cloned and characterized a gene from C. acuminata encoding the beta-subunit of tryptophan (Trp) synthase (TSB). In C. acuminata TSB provides Trp for both protein synthesis and indole alkaloid production and therefore represents a junction between primary and secondary metabolism. TSB mRNA and protein were detected in all C. acuminata organs examined, and their abundance paralleled that of camptothecin. Within each shoot organ, TSB was most abundant in vascular tissues. Within the root, however, TSB expression was most abundant in the outer cortex. TSB has been localized to chloroplasts in Arabidopsis, but there was little expression of TSB in C. acuminata tissues where the predominant plastids were photosynthetically competent chloroplasts. Expression of the promoter from the C. acuminata TSB gene in transgenic tobacco plants paralleled expression of the native gene in C. acuminata in all organs except roots. TSB is also highly expressed in C. acuminata during early seedling development at a stage corresponding to peak accumulation of camptothecin, consistent with the idea that Trp biosynthesis and the secondary indole alkaloid pathway are coordinately regulated.  (+info)

Expression of 1-aminocyclopropane-1-carboxylate oxidase during leaf ontogeny in white clover. (7/1498)

We examined the expression of three distinct 1-aminocyclopropane-1-carboxylic acid oxidase genes during leaf ontogeny in white clover (Trifolium repens). Significant production of ethylene occurs at the apex, in newly initiated leaves, and in senescent leaf tissue. We used a combination of reverse transcriptase-polymerase chain reaction and 3'-rapid amplification of cDNA ends to identify three distinct DNA sequences designated TRACO1, TRACO2, and TRACO3, each with homology to 1-aminocyclopropane-1-carboxylic acid oxidase. Southern analysis confirmed that these sequences represent three distinct genes. Northern analysis revealed that TRACO1 is expressed specifically in the apex and TRACO2 is expressed in the apex and in developing and mature green leaves, with maximum expression in developing leaf tissue. The third gene, TRACO3, is expressed in senescent leaf tissue. Antibodies were raised to each gene product expressed in Escherichia coli, and western analysis showed that the TRACO1 antibody recognizes a protein of approximately 205 kD (as determined by gradient sodium dodecyl sulfate-polyacylamide gel electrophoresis) that is expressed preferentially in apical tissue. The TRACO2 antibody recognizes a protein of approximately 36.4 kD (as determined by gradient sodium dodecyl sulfate-polyacylamide gel electrophoresis) that is expressed in the apex and in developing and mature green leaves, with maximum expression in mature green tissue. No protein recognition by the TRACO3 antibody could be detected in senescent tissue or at any other stage of leaf development.  (+info)

Evolution of the mitochondrial rps3 intron in perennial and annual angiosperms and homology to nad5 intron 1. (8/1498)

The plant mitochondrial rps3 intron was analyzed for substitution and indel rate variation among 15 monocot and dicot angiosperms from 10 genera, including perennial and annual taxa. Overall, the intron sequence was very conserved among angiosperms. Based on length polymorphism, 10 different alleles were identified among the 10 genera. These allelic differences were mainly attributable to large indels. An insertion of 133 nucleotides, observed in the Alnus intron was partially or completely absent in the other lineages of the family Betulaceae. This insertion was located within domain IV of the secondary-structure model of this group IIA intron. A mobile element of 47 nucleotides that showed homology to sequences located in rice rps3 intron and in intergenic plant mitochondrial genomes was found within this insertion. Both substitution and indel rates were low among the Betulaceae sequences, but substitution rates were increasingly larger than indel rates in comparisons involving more distantly related taxa. From a secondary-structure model, regions involved in helical structures were shown to be well preserved from indels as compared to substitutions, but compensatory changes were not observed among the angiosperm sequences analyzed. Using approximate divergence times based on the fossil record, substitution and indel rate heterogeneity was observed between different pairs of annual and perennial taxa. In particular, the annual petunia and primrose evolved more than 15 and 10 times faster, for substitution and indel rates respectively, than the perennial birch and alder. This is the first demonstration of an evolutionary rate difference between perennial and annual forms in noncoding DNA, lending support to neutral causes such as the generation time, population size, and speciation rate effects to explain such rate heterogeneity. Surprisingly, the sequence from the rps3 intron had a high identity with the sequence of intron 1 from the angiosperm mitochondrial nad5 gene, suggesting a common origin of these two group IIA introns.  (+info)

  • These studies generally have focused on the basal angiosperm splits, and more comprehensive taxon sampling is necessary to address backbone relationships throughout the angiosperms. (
  • Much adaptive or evolutionary potential in angiosperms is due to the activity of TEs (active TE-Thrust), resulting in an extraordinary array of genetic changes, including gene modifications, duplications, altered expression patterns, and exaptation to create novel genes, with occasional gene disruption. (
  • Phylogenetic analyses of angiosperm relationships have used only a small percentage of available sequence data, but phylogenetic data matrices often can be augmented with existing data, especially if one allows missing characters. (
  • While GenBank currently contains over 1.7 million core nucleotide sequences from angiosperms, with over 160,000 of these being from often phylogenetically useful plastid loci [ 6 ], few phylogenetic analyses of angiosperms have included more than a thousand sequences. (
  • Previous analyses of molecular data across all angiosperms mostly used complete or nearly complete data matrices (but see [ 25 , 26 ]), in which all taxa have sequences from all, or nearly all, genes. (
  • TEs implicated in the earliest origins of the angiosperms include the exapted Mustang, Sleeper, and Fhy3/Far1 gene families. (
  • Система APG IV - современная таксономическая система классификации цветковых растений , разработанная «Группой филогении покрытосеменных» ( Angiosperm Phylogeny Group , APG ) и опубликованная в марте 2016 года в Ботаническом журнале Лондонского Линнеевского общества в статье «An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV» . (
  • Systematika krytosymjenjakow po APG III je na kóncu lěta 2009 wuńdźena aktualizacija wot Angiosperm Phylogeny Group najprjedy w lěće 1998 (APG I) namjetana a w lěće 2003 předźěłana (APG II) systematika krytosymjenjakow . (
  • Recent large-scale studies of tree growth in the Iberian Peninsula reported contrasting positive and negative effects of temperature in Mediterranean angiosperms and conifers. (
  • Here we review the different hypotheses that may explain these trends and propose that the observed contrasting responses of tree growth to temperature in this region could be associated with a continuum of trait differences between angiosperms and conifers. (
  • Moreover, angiosperms and conifers significantly differ in hydraulic safety margins, sensitivity of stomatal conductance to vapor-pressure deficit (VPD), xylem recovery capacity or the rate of carbon transfer. (
  • Conifers dominated the world's forests prior to the Cretaceous radiation in angiosperm diversity. (
  • Contrary to prediction, leaf hydraulic conductance (normalized by projected leaf area) was unrelated to complexity of venation in conifers and angiosperms, but was highly correlated with whole-plant conductance. (
  • Analyses of published data showed that leafless branches of temperate deciduous angiosperms had higher leaf-area normalized hydraulic conductivity than conifers, but there was no significant difference in adult, whole-plant conductance between these taxa. (
  • Thus, at the branch level, conifers with narrow tracheids have less efficient transport than angiosperms with wider vessels, but variations in other resistance components and hydraulic architecture (e.g., sapwood/leaf area ratio) ultimately equalize the sufficiency of water transport to leaves of conifers and angiosperms. (
  • This defines a narrow band for the emergence of CEP genes in plants, from the divergence of lycophytes to the angiosperm/gymnosperm split. (
  • Both CEP genes and domains were found to have diversified in angiosperms, particularly in the Poaceae and Solanaceae plant families. (
  • Nuclear rRNA genes (rDNA) in angiosperms are arranged in long tandem repeating units, much like those of other higher eukaryotes. (
  • Key angiosperm innovations that were lost include the entire repertoire of stomatal genes(3), genes involved in the synthesis of terpenoids and ethylene signalling, and genes for ultraviolet protection and phytochromes for far-red sensing. (
  • Here we explore daily variations in the expression of clock genes in the marine angiosperm Posidonia oceanica along its bathymetric distribution, where plants are exposed to a natural cline of light and temperature. (
  • However, even today, it is not clear what group of nonflowering plants the angiosperms are most closely related to, or what the relationships of the early lineages of flowering plants are to one another. (
  • Angiosperms (flowering plants) are the most diverse of all major lineages of land plants and the dominant autotrophs in most terrestrial ecosystems. (
  • However, it is not known whether this 'passive dilution' mechanism is present in plant lineages other than angiosperms and is another key feature of the angiosperms' evolutionary success. (
  • Furthermore, the propensity for gene and genome duplications in angiosperms provides abundant raw material for novel floral features-emphasizing the importance of understanding the conservation and diversification of gene lineages and functions in studies of macroevolution. (
  • Based on evidence from living and fossil plants, the earliest angiosperms are usually thought to have had small stature. (
  • Although most studies show that Amborella and Nymphaeales are more basal than Austrobaileyales, and all three are more basal than the mesangiosperms, there is significant molecular evidence in favor of two different trees, one in which Amborella is sister to the rest of the angiosperms, and one in which a clade of Amborella and Nymphaeales is in this position. (
  • Only 2 years ago it seemed that a consensus, based on molecular data, would emerge on angiosperm relationships within 10 years ( 14 ). (
  • Incorporating molecular phylogenetics with morphological, chemical, developmental, and paleobotanical data, as well as presenting a more detailed account of early angiosperm fossils and important fossil information for each evolutionary branch of the angiosperms, the new edition integrates fossil evidence into a robust phylogenetic framework. (
  • How deep is the conflict between molecular and fossil evidence on the age of angiosperms? (
  • Molecular data have had an enormous impact on angiosperm phylogenetic hypotheses (e.g. [ 1 - 5 ]), and the abundance of new sequence data provides the potential for further resolving angiosperm relationships. (
  • Still, molecular phylogenetic studies across all angiosperms have utilized only a small fraction of the available sequence data. (
  • In this study, we take advantage of these new data to explore the relationship between recombination rate, genome structure, and patterns of molecular evolution throughout angiosperms in order to better characterize the broad macroevolutionary patterns of recombination rate variation and its possible consequences for genome evolution. (
  • Funk, J.L. and Amatangelo, K.L. (2013) Physiological Mechanisms Drive Differing Foliar Calcium Content in Ferns and Angiosperms. (
  • i) exclusive to the angiosperms, (ii) a conserved mechanism that evolved in the common ancestor of ferns and angiosperms, or (iii) has evolved continuously over time. (
  • The different general relationships between vein density and stomatal density in ferns and angiosperms suggests the groups have different optimum balances between the production of vein tissue dedicated to water supply and stomatal tissue for gas exchange. (
  • Fruits are derived from the maturing floral organs of the angiospermous plant and are therefore characteristic of angiosperms. (
  • For a comparison of angiosperms with the other major groups of plants, see plant , bryophyte , fern , lower vascular plant , and gymnosperm . (
  • The variety of forms found among angiosperms is greater than that of any other plant group. (
  • The trend of the evolution of the plant kingdom has been in the direction of the establishment of a vegetation of fixed habit and adapted to the vicissitudes of a life on land, and the Angiosperms are the highest expression of this evolution and constitute the dominant vegetation of the earth's surface at the present epoch. (
  • There is no land-area from the poles to the equator, where plant-life is possible, upon which Angiosperms are not found. (
  • plant sexuality is most diverse among angiosperms ? (
  • In physical appearances, the seed-bearing plants of the angiosperms have roots that will hold the plant in its position and gather minerals and vitamins for its nutrition. (
  • We examine whether augmenting existing plant data matrices with incomplete data assembled from publicly available sources can enhance the understanding of the backbone phylogenetic relationships across angiosperms. (
  • A close geometric link between veins and stomata in angiosperms ensures that investment in enhanced venous water transport provides the strongest net carbon return to the plant. (
  • In angiosperms, the main plant body is a sporophyte consisting of roots, stem and leaves. (
  • Here we report the genome of Zostera marina (L.), the first, to our knowledge, marine angiosperm to be fully sequenced. (
  • By analyzing whole-genome bisulfite sequencing data in a phylogenetic context, it becomes clear that there is extensive variation throughout angiosperms in gene body DNA methylation, euchromatic silencing of transposons and repeats, as well as silencing of heterochromatic transposons. (
  • Our results reveal the origin of angiosperms at the late Permian, ∼275 million years ago. (
  • The sudden origin of angiosperms in the fossil record poses unanswered questions on both the origins of flowering plants and their rapid spread and diversification. (
  • This absence of a link is explained because angiosperms have xylem tissue that specifically functions in either mechanical strength or water transport. (
  • Lignin in angiosperms is composed of guaiacyl and syringyl monomers, whereas gymnosperm lignin consists almost entirely of guaiacyl moieties ( 1 ). (
  • The importance of the syringyl constituent in facilitating overall lignin degradation for more efficient materials and energy production from angiosperm than from gymnosperm wood has long been established ( 2 - 4 ). (
  • The male gametophyte in angiosperms is significantly reduced in size compared to those of gymnosperm seed plants. (
  • To Charles Darwin the suddenness of the angiosperm appearance and their rapid rise to dominance in the fossil record was both a "perplexing phenomenon" to "those who believe in extremely gradual evolution" and an "abominable mystery" ( 1 ). (
  • Added Crane: "This is the first time that we have had direct fossil evidence of the embryos of early angiosperms and how they compare with those of living plants. (
  • It provides information about the historical background of palynology from Palaeogene and Neogene sediments in India, general pollen morphology along with the terms commonly used in describing fossil angiosperm pollen and an overview of the Indian Tertiary sediments. (
  • It also includes a key for identification of Indian angiosperm genera as well as a description of selected fossil angiosperm pollen from India along with their Indian records, illustrations, locality, age and horizon from where these have been reported. (
  • These distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants and the most commercially important group to humans. (
  • This is important because it suggests that while early angiosperms may have had many characteristics of modern weedy early colonizers, they would have been unable to match the very rapid germination of the many different kinds of angiosperm herbs that evolved later and that ultimately proved even more effective in exploiting ephemeral ecological opportunities," Friis said. (
  • The tiny embryo shown in 3D has two rudimentary cotyledon primordia documenting the dicotyledonous nature of this extinct angiosperm. (
  • We also collected associated soil to measure the effect of soil conditions on AMF colonization Results Thick-root magnoliids showed less variation in root traits along root orders than more-derived angiosperm groups. (
  • article{osti_1247638, title = {Phylogenetically structured traits in root systems influence arbuscular mycorrhizal colonization in woody angiosperms}, author = {Valverde-Barrantes, Oscar J. and Horning, Amber L. and Smemo, Kurt A. and Blackwood, Christopher B.}, abstractNote = {In this study, there is little quantitative information about the relationship between root traits and the extent of arbuscular mycorrhizal fungi (AMF) colonization. (
  • the vast majority of the world's crops are angiosperms, as are most natural clothing fibers. (
  • However, some current studies suggest that endosperm is not unique to angiosperms. (
  • Because of the involvement of two fusions, this event is termed as double fertilisation, an event unique to angiosperms. (