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42-666: The Nottingham Arabidopsis Stock Centre ( NASC ) provides seed and information resources to the International Arabidopsis Genome Project and the wider research community. It is based in the School of Biosciences at the University of Nottingham 's Sutton Bonington Campus , in the English county of Nottinghamshire . It holds more than 800,000 different stocks of seed representing nearly a million genotypes and provided

84-684: A Genechip service from 2002-2013. Newly generated research stocks, mutants or lines of Arabidopsis thaliana are donated as samples to NASC where they are maintained and thus are made available to scientists worldwide. Established in 1990 as part of the Plant Molecular Biology initiative of the Agricultural and Food Research Council (AFRC), the Centre is currently funded by the Biotechnology and Biological Sciences Research Council ( BBSRC ) and

126-532: A distribution agreement. NASC distributes to Europe and ABRC distributes to the Americas . Laboratories in other locations may establish their primary affiliation with either centre. When NASC started in 1990 it inherited hundreds of stocks from the Arabidopsis Information Service (AIS) - Started by Robbelen in 1965 and continued by Burger (1971), Kranz (1978), and Kranz and Kirchheim (1981, 1987),

168-423: A genome, and what those genes do. There may also be related projects to sequence ESTs or mRNAs to help find out where the genes actually are. Historically, when sequencing eukaryotic genomes (such as the worm Caenorhabditis elegans ) it was common to first map the genome to provide a series of landmarks across the genome. Rather than sequence a chromosome in one go, it would be sequenced piece by piece (with

210-514: A new genome sequence has steadily fallen (in terms of cost per base pair ) and newer technology has also meant that genomes can be sequenced far more quickly. When research agencies decide what new genomes to sequence, the emphasis has been on species which are either high importance as model organism or have a relevance to human health (e.g. pathogenic bacteria or vectors of disease such as mosquitos ) or species which have commercial importance (e.g. livestock and crop plants). Secondary emphasis

252-545: A protective response. The first such plant receptors were identified in rice and in Arabidopsis thaliana . Plants have some of the largest genomes of all organisms. The largest plant genome (in terms of gene number) is that of wheat ( Triticum aestivum ), predicted to encode ≈94,000 genes and thus almost 5 times as many as the human genome . The first plant genome sequenced was that of Arabidopsis thaliana which encodes about 25,500 genes. In terms of sheer DNA sequence,

294-420: A range of physical and biotic stresses which cause DNA damage , but they can tolerate and repair much of this damage. Plants reproduce to generate offspring, whether sexually , involving gametes , or asexually , involving ordinary growth. Many plants use both mechanisms. When reproducing sexually, plants have complex lifecycles involving alternation of generations . One generation, the sporophyte , which

336-404: Is diploid (with 2 sets of chromosomes ), gives rise to the next generation, the gametophyte , which is haploid (with one set of chromosomes). Some plants also reproduce asexually via spores . In some non-flowering plants such as mosses, the sexual gametophyte forms most of the visible plant. In seed plants (gymnosperms and flowering plants), the sporophyte forms most of the visible plant, and

378-547: Is a similar process. Structures such as runners enable plants to grow to cover an area, forming a clone . Many plants grow food storage structures such as tubers or bulbs which may each develop into a new plant. Some non-flowering plants, such as many liverworts, mosses and some clubmosses, along with a few flowering plants, grow small clumps of cells called gemmae which can detach and grow. Plants use pattern-recognition receptors to recognize pathogens such as bacteria that cause plant diseases. This recognition triggers

420-496: Is known as botany , a branch of biology . All living things were traditionally placed into one of two groups, plants and animals . This classification dates from Aristotle (384–322 BC), who distinguished different levels of beings in his biology , based on whether living things had a "sensitive soul" or like plants only a "vegetative soul". Theophrastus , Aristotle's student, continued his work in plant taxonomy and classification. Much later, Linnaeus (1707–1778) created

462-588: Is placed on species whose genomes will help answer important questions in molecular evolution (e.g. the common chimpanzee ). In the future, it is likely that it will become even cheaper and quicker to sequence a genome. This will allow for complete genome sequences to be determined from many different individuals of the same species. For humans, this will allow us to better understand aspects of human genetic diversity . Many organisms have genome projects that have either been completed or will be completed shortly, including: Plant See text Plants are

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504-419: Is produced by combining the information sequenced contigs and then employing linking information to create scaffolds. Scaffolds are positioned along the physical map of the chromosomes creating a "golden path". Originally, most large-scale DNA sequencing centers developed their own software for assembling the sequences that they produced. However, this has changed as the software has grown more complex and as

546-467: Is the process of identifying attaching biological information to sequences , and particularly in identifying the locations of genes and determining what those genes do. When sequencing a genome, there are usually regions that are difficult to sequence (often regions with highly repetitive DNA ). Thus, 'completed' genome sequences are rarely ever complete, and terms such as 'working draft' or 'essentially complete' have been used to more accurately describe

588-679: The Cretaceous so rapid that Darwin called it an " abominable mystery ". Conifers diversified from the Late Triassic onwards, and became a dominant part of floras in the Jurassic . In 2019, a phylogeny based on genomes and transcriptomes from 1,153 plant species was proposed. The placing of algal groups is supported by phylogenies based on genomes from the Mesostigmatophyceae and Chlorokybophyceae that have since been sequenced. Both

630-504: The University of Nottingham . The Stock Centre was founded by Dr Bernard Mulligan; Directed from 1991 to 1999 by Dr Mary Anderson and from 1999–present by Prof. Sean Tobias May. NASC's activities are coordinated with those of the Arabidopsis Biological Resource Center, (ABRC) based at Ohio State University , USA. This facilitates a unified and efficient service for the research community. The stock centres have

672-457: The carpels or ovaries , which develop into fruits that contain seeds . Fruits may be dispersed whole, or they may split open and the seeds dispersed individually. Plants reproduce asexually by growing any of a wide variety of structures capable of growing into new plants. At the simplest, plants such as mosses or liverworts may be broken into pieces, each of which may regrow into whole plants. The propagation of flowering plants by cuttings

714-618: The eukaryotes that form the kingdom Plantae ; they are predominantly photosynthetic . This means that they obtain their energy from sunlight , using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars from carbon dioxide and water, using the green pigment chlorophyll . Exceptions are parasitic plants that have lost the genes for chlorophyll and photosynthesis, and obtain their energy from other plants or fungi. Most plants are multicellular , except for some green algae. Historically, as in Aristotle's biology ,

756-1003: The "chlorophyte algae" and the "streptophyte algae" are treated as paraphyletic (vertical bars beside phylogenetic tree diagram) in this analysis, as the land plants arose from within those groups. The classification of Bryophyta is supported both by Puttick et al. 2018, and by phylogenies involving the hornwort genomes that have also since been sequenced. Rhodophyta [REDACTED] Glaucophyta [REDACTED] Chlorophyta [REDACTED] Prasinococcales   Mesostigmatophyceae Chlorokybophyceae Spirotaenia [REDACTED] Klebsormidiales [REDACTED] Chara [REDACTED] Coleochaetales [REDACTED] Hornworts [REDACTED] Liverworts [REDACTED] Mosses [REDACTED] Lycophytes [REDACTED] [REDACTED] Gymnosperms [REDACTED] Angiosperms [REDACTED] Plant cells have distinctive features that other eukaryotic cells (such as those of animals) lack. These include

798-537: The AIS donated its complement of stocks listed in the 24th edition of the AIS stock book. Stock numbers held at NASC/ABRC in the 1990s then increased steadily by many hundreds mainly due to new technologies of mass transformation (e.g. seed transformation by Ken Feldmann, University of Arizona); but also due to many new mutagenesis programs encouraged by the development of Arabidopsis as a major model organism accompanied by generous donations of seed from many international members of

840-445: The DNA originated. In a shotgun sequencing project, all the DNA from a source (usually a single organism , anything from a bacterium to a mammal ) is first fractured into millions of small pieces. These pieces are then "read" by automated sequencing machines. A genome assembly algorithm works by taking all the pieces and aligning them to one another, and detecting all places where two of

882-470: The SALK lines from Joe Ecker. Between them, these two populations account for more than half of all stocks held by the stock centres today. Genome Project The Human Genome Project is a well known example of a genome project. Genome assembly refers to the process of taking a large number of short DNA sequences and reassembling them to create a representation of the original chromosomes from which

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924-857: The Viridiplantae, along with the red algae and the glaucophytes , in the clade Archaeplastida . There are about 380,000 known species of plants, of which the majority, some 260,000, produce seeds . They range in size from single cells to the tallest trees . Green plants provide a substantial proportion of the world's molecular oxygen; the sugars they create supply the energy for most of Earth's ecosystems and other organisms , including animals, either eat plants directly or rely on organisms which do so. Grain , fruit , and vegetables are basic human foods and have been domesticated for millennia. People use plants for many purposes , such as building materials , ornaments, writing materials , and, in great variety, for medicines . The scientific study of plants

966-801: The amount of cytoplasm stays the same. Most plants are multicellular . Plant cells differentiate into multiple cell types, forming tissues such as the vascular tissue with specialized xylem and phloem of leaf veins and stems , and organs with different physiological functions such as roots to absorb water and minerals, stems for support and to transport water and synthesized molecules, leaves for photosynthesis, and flowers for reproduction. Plants photosynthesize , manufacturing food molecules ( sugars ) using energy obtained from light . Plant cells contain chlorophylls inside their chloroplasts, which are green pigments that are used to capture light energy. The end-to-end chemical equation for photosynthesis is: This causes plants to release oxygen into

1008-431: The atmosphere. Green plants provide a substantial proportion of the world's molecular oxygen, alongside the contributions from photosynthetic algae and cyanobacteria. Plants that have secondarily adopted a parasitic lifestyle may lose the genes involved in photosynthesis and the production of chlorophyll. Growth is determined by the interaction of a plant's genome with its physical and biotic environment. Factors of

1050-461: The basis of the modern system of scientific classification , but retained the animal and plant kingdoms , naming the plant kingdom the Vegetabilia. When the name Plantae or plant is applied to a specific group of organisms or taxa , it usually refers to one of four concepts. From least to most inclusive, these four groupings are: There are about 382,000 accepted species of plants, of which

1092-509: The community. In 1999 NASC received a large influx of thousands of stocks generated through T-DNA transformation and donated by Pelletier and Bechtold from INRA . This was the first of many very large populations that came out of the community and which took the complement of stocks held by the stock centres into the hundreds of thousands. The largest (most populous) seed donations have been the GABI-kat lines from Germany via Bernd Weisshaar; and

1134-483: The development of forests in swampy environments dominated by clubmosses and horsetails, including some as large as trees, and the appearance of early gymnosperms , the first seed plants . The Permo-Triassic extinction event radically changed the structures of communities. This may have set the scene for the evolution of flowering plants in the Triassic (~ 200  million years ago ), with an adaptive radiation in

1176-409: The gametophyte is very small. Flowering plants reproduce sexually using flowers, which contain male and female parts: these may be within the same ( hermaphrodite ) flower, on different flowers on the same plant , or on different plants . The stamens create pollen , which produces male gametes that enter the ovule to fertilize the egg cell of the female gametophyte. Fertilization takes place within

1218-461: The goal of sequencing a genome is to obtain information about the complete set of genes in that particular genome sequence. The proportion of a genome that encodes for genes may be very small (particularly in eukaryotes such as humans, where coding DNA may only account for a few percent of the entire sequence). However, it is not always possible (or desirable) to only sequence the coding regions separately. Also, as scientists understand more about

1260-575: The great majority, some 283,000, produce seeds . The table below shows some species count estimates of different green plant (Viridiplantae) divisions . About 85–90% of all plants are flowering plants. Several projects are currently attempting to collect records on all plant species in online databases, e.g. the World Flora Online . Plants range in scale from single-celled organisms such as desmids (from 10  micrometres   (μm) across) and picozoa (less than 3 μm across), to

1302-517: The land 1,200  million years ago , but it was not until the Ordovician , around 450  million years ago , that the first land plants appeared, with a level of organisation like that of bryophytes. However, fossils of organisms with a flattened thallus in Precambrian rocks suggest that multicellular freshwater eukaryotes existed over 1000 mya. Primitive land plants began to diversify in

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1344-412: The large water-filled central vacuole , chloroplasts , and the strong flexible cell wall , which is outside the cell membrane . Chloroplasts are derived from what was once a symbiosis of a non-photosynthetic cell and photosynthetic cyanobacteria . The cell wall, made mostly of cellulose , allows plant cells to swell up with water without bursting. The vacuole allows the cell to change in size while

1386-507: The largest trees ( megaflora ) such as the conifer Sequoia sempervirens (up to 120 metres (380 ft) tall) and the angiosperm Eucalyptus regnans (up to 100 m (325 ft) tall). The naming of plants is governed by the International Code of Nomenclature for algae, fungi, and plants and the International Code of Nomenclature for Cultivated Plants . The ancestors of land plants evolved in water. An algal scum formed on

1428-656: The late Silurian , around 420  million years ago . Bryophytes, club mosses, and ferns then appear in the fossil record. Early plant anatomy is preserved in cellular detail in an early Devonian fossil assemblage from the Rhynie chert . These early plants were preserved by being petrified in chert formed in silica-rich volcanic hot springs. By the end of the Devonian, most of the basic features of plants today were present, including roots, leaves and secondary wood in trees such as Archaeopteris . The Carboniferous period saw

1470-418: The number of sequencing centers has increased. An example of such assembler Short Oligonucleotide Analysis Package developed by BGI for de novo assembly of human-sized genomes, alignment, SNP detection, resequencing, indel finding, and structural variation analysis. Since the 1980s, molecular biology and bioinformatics have created the need for DNA annotation . DNA annotation or genome annotation

1512-501: The physical or abiotic environment include temperature , water , light, carbon dioxide , and nutrients in the soil. Biotic factors that affect plant growth include crowding, grazing, beneficial symbiotic bacteria and fungi, and attacks by insects or plant diseases . Frost and dehydration can damage or kill plants. Some plants have antifreeze proteins , heat-shock proteins and sugars in their cytoplasm that enable them to tolerate these stresses . Plants are continuously exposed to

1554-538: The plant kingdom encompassed all living things that were not animals , and included algae and fungi . Definitions have narrowed since then; current definitions exclude the fungi and some of the algae. By the definition used in this article, plants form the clade Viridiplantae (green plants), which consists of the green algae and the embryophytes or land plants ( hornworts , liverworts , mosses , lycophytes , ferns , conifers and other gymnosperms , and flowering plants ). A definition based on genomes includes

1596-461: The prior knowledge of approximately where that piece is located on the larger chromosome). Changes in technology and in particular improvements to the processing power of computers, means that genomes can now be ' shotgun sequenced ' in one go (there are caveats to this approach though when compared to the traditional approach). Improvements in DNA sequencing technology have meant that the cost of sequencing

1638-405: The role of this noncoding DNA (often referred to as junk DNA ), it will become more important to have a complete genome sequence as a background to understanding the genetics and biology of any given organism. In many ways genome projects do not confine themselves to only determining a DNA sequence of an organism. Such projects may also include gene prediction to find out where the genes are in

1680-459: The short sequences, or reads , overlap. These overlapping reads can be merged, and the process continues. Genome assembly is a very difficult computational problem, made more difficult because many genomes contain large numbers of identical sequences, known as repeats . These repeats can be thousands of nucleotides long, and occur different locations, especially in the large genomes of plants and animals . The resulting (draft) genome sequence

1722-465: The smallest published genome is that of the carnivorous bladderwort ( Utricularia gibba) at 82 Mb (although it still encodes 28,500 genes) while the largest, from the Norway spruce ( Picea abies ), extends over 19.6 Gb (encoding about 28,300 genes). Plants are distributed almost worldwide. While they inhabit several biomes which can be divided into a multitude of ecoregions , only the hardy plants of

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1764-418: The status of such genome projects. Even when every base pair of a genome sequence has been determined, there are still likely to be errors present because DNA sequencing is not a completely accurate process. It could also be argued that a complete genome project should include the sequences of mitochondria and (for plants) chloroplasts as these organelles have their own genomes. It is often reported that

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