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History Of Research On Arabidopsis Thaliana
''Arabidopsis thaliana'' is a first class model organism and the single most important species for fundamental research in plant molecular genetics. ''A. thaliana'' was the first plant for which a high-quality reference genome sequence was determined (see below), and a worldwide research community has developed many other genetic resources and tools. The experimental advantages of ''A. thaliana'' have enabled many important discoveries. These advantages have been extensively reviewed, as has its role in fundamental discoveries about the plant immune system, natural variation, root biology, and other areas. Early history ''A. thaliana'' was first described by Johannes Thal, and later renamed in his honor. (See the Taxonomy section of the main article.) Friedrich Laibach outlined why ''A. thaliana'' might be a good experimental system in 1943 and collected a large number of natural accessions. A. thaliana is largely self-pollinating, so these accessions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arabidopsis Thaliana
''Arabidopsis thaliana'', the thale cress, mouse-ear cress or arabidopsis, is a small flowering plant native to Eurasia and Africa. ''A. thaliana'' is considered a weed; it is found along the shoulders of roads and in disturbed land. A winter annual with a relatively short lifecycle, ''A. thaliana'' is a popular model organism in plant biology and genetics. For a complex multicellular eukaryote, ''A. thaliana'' has a relatively small genome around 135 mega base pairs. It was the first plant to have its genome sequenced, and is a popular tool for understanding the molecular biology of many plant traits, including flower development and light sensing. Description ''Arabidopsis thaliana'' is an annual (rarely biennial) plant, usually growing to 20–25 cm tall. The leaves form a rosette at the base of the plant, with a few leaves also on the flowering stem. The basal leaves are green to slightly purplish in color, 1.5–5 cm long, and 2–10 mm broad, with an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ABC Model Of Flower Development
The ABC model of flower development is a scientific model of the process by which flowering plants produce a pattern of gene expression in meristems that leads to the appearance of an organ oriented towards sexual reproduction, a flower. There are three physiological developments that must occur in order for this to take place: firstly, the plant must pass from sexual immaturity into a sexually mature state (i.e. a transition towards flowering); secondly, the transformation of the apical meristem's function from a vegetative meristem into a floral meristem or inflorescence; and finally the growth of the flower's individual organs. The latter phase has been modelled using the ABC model, which aims to describe the biological basis of the process from the perspective of molecular and developmental genetics. An external stimulus is required in order to trigger the differentiation of the meristem into a flower meristem. This stimulus will activate mitotic cell division in the api ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recombinant Inbred Strain
A recombinant inbred strain or recombinant inbred line (RIL) is an organism with chromosomes that incorporate an essentially permanent set of recombination events between chromosomes inherited from two or more inbred strains. F1 and F2 generations are produced by intercrossing the inbred strains; pairs of the F2 progeny are then mated to establish inbred strains through long-term inbreeding. Families of recombinant inbred strains numbering from 25 to 5000 are often used to map the locations of DNA sequence differences (quantitative trait loci) that contributed to differences in phenotype in model organisms. Recombinant inbred strains or lines were first developed using inbred strains of mice but are now used to study a wide range of organisms – ''Saccharomyces cerevisiae'' (yeast), ''Zea mays'' (maize), barley, ''Drosophila melanogaster'', ''C. elegans'' and rat. History The origins and history of recombinant inbred strains are described by Crow. While the potential utility of r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forward Genetics
Forward genetics is a molecular genetics approach of determining the genetic basis responsible for a phenotype. Forward genetics provides an unbiased approach because it relies heavily on identifying the genes or genetic factors that cause a particular phenotype or trait of interest. This was initially done by using naturally occurring mutations or inducing mutants with radiation, chemicals, or insertional mutagenesis (e.g. transposable elements). Subsequent breeding takes place, mutant individuals are isolated, and then the gene is mapped. Forward genetics can be thought of as a counter to reverse genetics, which determines the function of a gene by analyzing the phenotypic effects of altered DNA sequences. Mutant phenotypes are often observed long before having any idea which gene is responsible, which can lead to genes being named after their mutant phenotype (e.g. Drosophila ''rosy'' gene which is named after the eye colour in mutants). Techniques used in Forward Genetics Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Map-based Cloning
A genetic screen or mutagenesis screen is an experimental technique used to identify and select individuals who possess a phenotype In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological pr ... of interest in a mutagenized population. Hence a genetic screen is a type of phenotypic screen. Genetic screens can provide important information on gene function as well as the molecular events that underlie a biological process or pathway. While genome projects have identified an extensive inventory of genes in many different organisms, genetic screens can provide valuable insight as to how those genes function. Basic screening Forward genetics (or a forward genetic screen) starts with a phenotype and then attempts to identify the causative mutation and thus gene(s) responsible for the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Marker
A genetic marker is a gene or DNA sequence with a known location on a chromosome that can be used to identify individuals or species. It can be described as a variation (which may arise due to mutation or alteration in the genomic loci) that can be observed. A genetic marker may be a short DNA sequence, such as a sequence surrounding a single base-pair change ( single nucleotide polymorphism, SNP), or a long one, like minisatellites. Background For many years, gene mapping was limited to identifying organisms by traditional phenotypes markers. This included genes that encoded easily observable characteristics such as blood types or seed shapes. The insufficient number of these types of characteristics in several organisms limited the mapping efforts that could be done. This prompted the development of gene markers which could identify genetic characteristics that are not readily observable in organisms (such as protein variation). Types Some commonly used types of genetic markers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Map
Genetic linkage is the tendency of DNA sequences that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction. Two genetic markers that are physically near to each other are unlikely to be separated onto different chromatids during chromosomal crossover, and are therefore said to be more ''linked'' than markers that are far apart. In other words, the nearer two genes are on a chromosome, the lower the chance of recombination between them, and the more likely they are to be inherited together. Markers on different chromosomes are perfectly ''unlinked'', although the penetrance of potentially deleterious alleles may be influenced by the presence of other alleles, and these other alleles may be located on other chromosomes than that on which a particular potentially deleterious allele is located. Genetic linkage is the most prominent exception to Gregor Mendel's Law of Independent Assortment. The first experiment to demonstrate lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcohol Dehydrogenase
Alcohol dehydrogenases (ADH) () are a group of dehydrogenase enzymes that occur in many organisms and facilitate the interconversion between alcohols and aldehydes or ketones with the reduction of nicotinamide adenine dinucleotide (NAD+) to NADH. In humans and many other animals, they serve to break down alcohols that otherwise are toxic, and they also participate in generation of useful aldehyde, ketone, or alcohol groups during biosynthesis of various metabolites. In yeast, plants, and many bacteria, some alcohol dehydrogenases catalyze the opposite reaction as part of fermentation to ensure a constant supply of NAD+. Evolution Genetic evidence from comparisons of multiple organisms showed that a glutathione-dependent formaldehyde dehydrogenase, identical to a class III alcohol dehydrogenase (ADH-3/ADH5), is presumed to be the ancestral enzyme for the entire ADH family. Early on in evolution, an effective method for eliminating both endogenous and exogenous formaldehyde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudomonas Syringae
''Pseudomonas syringae'' is a rod-shaped, Gram-negative bacterium with polar flagella. As a plant pathogen, it can infect a wide range of species, and exists as over 50 different pathovars, all of which are available to researchers from international culture collections such as the NCPPB, ICMP, and others. ''Pseudomonas syringae'' is a member of the genus ''Pseudomonas'', and based on 16S rRNA analysis, it has been placed in the ''P. syringae'' group. It is named after the lilac tree (''Syringa vulgaris''), from which it was first isolated. A phylogenomic analysis of 494 complete genomes from the entire ''Pseudomonas'' genus showed that ''P. syringae'' does not form a monophyletic species in the strict sense, but a wider evolutionary group that also included other species as well, such as ''P. avellanae'', ''P. savastanoi'', ''P. amygdali'', and ''P. cerasi''. ''Pseudomonas syringae'' tests negative for arginine dihydrolase and oxidase activity, and forms the polymer levan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyaloperonospora Arabidopsidis
''Hyaloperonospora arabidopsidis'' is a species from the family Peronosporaceae. It is an obligate parasite and the causal agent of the downy mildew of the plant model organism ''Arabidopsis thaliana''. While ''H. arabidopsidis'' has for a long time been subsumed under ''Peronospora parasitica'' (now ''Hyaloperonospora parasitica''), recent studies have shown that ''H. parasitica'' is restricted to ''Capsella bursa-pastoris'' as a host plant. Like the other ''Hyaloperonospora'' species, ''H. arabidopsidis'' is highly specialized to ''Arabidopsis thaliana''. References * Further reading Peronosporales Water mould plant pathogens and diseases Eudicot diseases Arabidopsis thaliana {{plant-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederick M
Frederick may refer to: People * Frederick (given name), the name Nobility Anhalt-Harzgerode *Frederick, Prince of Anhalt-Harzgerode (1613–1670) Austria * Frederick I, Duke of Austria (Babenberg), Duke of Austria from 1195 to 1198 * Frederick II, Duke of Austria (1219–1246), last Duke of Austria from the Babenberg dynasty * Frederick the Fair (Frederick I of Austria (Habsburg), 1286–1330), Duke of Austria and King of the Romans Baden * Frederick I, Grand Duke of Baden (1826–1907), Grand Duke of Baden * Frederick II, Grand Duke of Baden (1857–1928), Grand Duke of Baden Bohemia * Frederick, Duke of Bohemia (died 1189), Duke of Olomouc and Bohemia Britain * Frederick, Prince of Wales (1707–1751), eldest son of King George II of Great Britain Brandenburg/Prussia * Frederick I, Elector of Brandenburg (1371–1440), also known as Frederick VI, Burgrave of Nuremberg * Frederick II, Elector of Brandenburg (1413–1470), Margrave of Brandenburg * Frederick William, Elector ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerald Fink
Gerald Ralph Fink (born July 1, 1940) is an American biologist, who was Director of the Whitehead Institute at MIT from 1990–2001. He graduated from Amherst College in 1962 and received a Ph.D. from Yale University in 1965, having elucidated the histidine pathway in budding yeast, ''Saccharomyces cerevisiae''. After postdoctoral study at the National Institutes of Health with Bruce Ames on the regulation of the histidine operon of Salmonella, in 1967 he joined Cornell University where he became a Professor of Genetics and pursued the study of the HIS4 region of yeast. In 1982 he became a founding member of the Whitehead Institute and Professor of Genetics at MIT. Dr. Fink was elected to the United States National Academy of Sciences in 1981, to the Institute of Medicine in 1996, and to the American Philosophical Society in 2003. Fink taught a course in the Molecular Biology of Yeast at Cold Spring Harbor Laboratory for 16 years. Many of these students as well as his univer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
