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Jasmonate
Jasmonate (JA) and its derivatives are lipid-based plant hormones that regulate a wide range of processes in plants, ranging from growth and photosynthesis to reproductive development. In particular, JAs are critical for plant defense against herbivory and plant responses to poor environmental conditions and other kinds of abiotic and biotic challenges. Some JAs can also be released as volatile organic compounds (VOCs) to permit communication between plants in anticipation of mutual dangers. History The isolation of methyl jasmonate (MeJa) from jasmine oil derived from '' Jasminum grandiflorum'' led to the discovery of the molecular structure of jasmonates and their name in 1962 while jasmonic acid itself was isolated from '' Lasiodiplodia theobromae'' by Alderidge et al in 1971. Biosynthesis Biosynthesis is reviewed by Acosta and Farmer 2010, Wasternack and Hause 2013, and Wasternack and Song 2017. Jasmonates (JA) are oxylipins, i.e. derivatives of oxygenated fatty acid. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Jasmonate
Methyl jasmonate (abbreviated MeJA) is a volatile organic compound used in plant defense and many diverse developmental pathways such as seed germination, root growth, flowering, fruit ripening, and senescence. Methyl jasmonate is derived from jasmonic acid and the reaction is catalyzed by ''S''-adenosyl--methionine:jasmonic acid carboxyl methyltransferase. Description Plants produce jasmonic acid and methyl jasmonate in response to many biotic and abiotic stresses (in particular, herbivory and wounding), which build up in the damaged parts of the plant. The methyl jasmonate can be used to signal the original plant’s defense systems or it can be spread by physical contact or through the air to produce a defensive reaction in unharmed plants. The unharmed plants absorb the airborne MeJA through either the stomata or diffusion through the leaf cell cytoplasm. An herbivorous attack on a plant causes it to produce MeJA both for internal defense and for a signaling compound to o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JA-Ile
Jasmonate (JA) and its derivatives are lipid-based plant hormones that regulate a wide range of processes in plants, ranging from growth and photosynthesis to reproductive development. In particular, JAs are critical for plant defense against herbivory and plant responses to poor environmental conditions and other kinds of abiotic and biotic challenges. Some JAs can also be released as volatile organic compounds (VOCs) to permit communication between plants in anticipation of mutual dangers. History The isolation of methyl jasmonate (MeJa) from jasmine oil derived from ''Jasminum grandiflorum'' led to the discovery of the molecular structure of jasmonates and their name in 1962 while jasmonic acid itself was isolated from '' Lasiodiplodia theobromae'' by Alderidge et al in 1971. Biosynthesis Biosynthesis is reviewed by Acosta and Farmer 2010, Wasternack and Hause 2013, and Wasternack and Song 2017. Jasmonates (JA) are oxylipins, i.e. derivatives of oxygenated fatty acid. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Hormone
Plant hormone (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, from embryogenesis, the regulation of organ size, pathogen defense, stress tolerance and through to reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book. Phytohormones occur across the plant kingdom, and even in algae, where they have similar functions to those seen in higher plants. Some phytohormones also occur in microorganisms, such as unicellular fungi and bacteria, however in these cases they do not play a hormonal role and can better be regarded as secondary metabolites. Characteristics The word hormone is derived from Greek, meaning ''set in motion''. Plant hormones affect gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jasmonic Acid
Jasmonic acid (JA) is an organic compound found in several plants including jasmine. The molecule is a member of the jasmonate class of plant hormones. It is biosynthesized from linolenic acid by the octadecanoid pathway. It was first isolated in 1957 as the methyl ester of jasmonic acid by the Swiss chemist Edouard Demole and his colleagues. Biosynthesis Its biosynthesis starts from the fatty acid linolenic acid, which is oxygenated by lipoxygenase (13-LOX), forming a hydroperoxide. This peroxide then cyclizes in the presence of allene oxide synthase to form an allene oxide. The rearrangement of allene oxide to form 12-oxophytodienoic acid is catalyzed by the enzyme allene oxide cyclase. A series of β-oxidations result in 7-iso-jasmonic acid. In the absence of enzyme, this iso-jasmonic acid isomerizes to jasmonic acid. Function The major function of JA and its various metabolites is regulating plant responses to abiotic and biotic stresses as well as plant growth and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloroplast
A chloroplast () is a type of membrane-bound organelle known as a plastid that conducts photosynthesis mostly in plant and algal cells. The photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water in the cells. The ATP and NADPH is then used to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies from one, in unicellular algae, up to 100 in plants like '' Arabidopsis'' and wheat. A chloroplast is characterized by its two membranes and a high concentration of chlorophyll. Other plastid types, such as the leucoplast and the chromoplast, contain little chlorophyll and do not carry out photosynthesis. Chloroplasts are highly dynamic—they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxylipin
Oxylipins constitute a family of oxygenated natural products which are formed from fatty acids by pathways involving at least one step of dioxygen-dependent oxidation. Oxylipins are derived from polyunsaturated fatty acids (PUFAs) by COX enzymes ( cyclooxygenases), by LOX enzymes (lipoxygenases), or by cytochrome P450 epoxygenase. Oxylipins are widespread in aerobic organisms including plants, animals and fungi. Many of oxylipins have physiological significance. Typically, oxylipins are not stored in tissues but are formed on demand by liberation of precursor fatty acids from esterified forms. Biosynthesis Biosynthesis of oxylipins is initiated by dioxygenases or monooxygenases; however also non- enzymatic autoxidative processes contribute to oxylipin formation (phytoprostanes, isoprostanes). Dioxygenases include lipoxygenases (plants, animals, fungi), heme-dependent fatty acid oxygenases (plants, fungi), and cyclooxygenases (animals). Fatty acid hydroperoxides or endo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venus Flytrap
The Venus flytrap (''Dionaea muscipula'') is a carnivorous plant native to subtropical wetlands on the East Coast of the United States in North Carolina and South Carolina. It catches its prey—chiefly insects and arachnids—with a trapping structure formed by the terminal portion of each of the plant's leaves, which is triggered by tiny hairs (called "trigger hairs" or "sensitive hairs") on their inner surfaces. When an insect or spider crawling along the leaves contacts a hair, the trap prepares to close, snapping shut only if another contact occurs within approximately twenty seconds of the first strike. Triggers may occur with a tenth of a second of contact. The requirement of redundant triggering in this mechanism serves as a safeguard against wasting energy by trapping objects with no nutritional value, and the plant will only begin digestion after five more stimuli to ensure it has caught a live bug worthy of consumption. ''Dionaea'' is a monotypic genus closely rela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondria
A mitochondrion (; ) is an organelle found in the cells of most Eukaryotes, such as animals, plants and fungi. Mitochondria have a double membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into other structures. One eukaryote, '' Monocercomonoides'', is known to have completely lost its mitochondria, and one multicellular orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apoptosis
Apoptosis (from grc, ἀπόπτωσις, apóptōsis, 'falling off') is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes ( morphology) and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, DNA fragmentation, and mRNA decay. The average adult human loses between 50 and 70 billion cells each day due to apoptosis. For an average human child between eight and fourteen years old, approximately twenty to thirty billion cells die per day. In contrast to necrosis, which is a form of traumatic cell death that results from acute cellular injury, apoptosis is a highly regulated and controlled process that confers advantages during an organism's life cycle. For example, the separation of fingers and toes in a developing human embryo occurs because cells between the digits undergo apoptosis. Unlike necrosis, apoptosis produces cell fragments called apopt ... [...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 megabase 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, wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germination
Germination is the process by which an organism grows from a seed or spore. The term is applied to the sprouting of a seedling from a seed of an angiosperm or gymnosperm, the growth of a sporeling from a spore, such as the spores of fungi, ferns, bacteria, and the growth of the pollen tube from the pollen grain of a seed plant. Seed plants Germination is usually the growth of a plant contained within a seed; it results in the formation of the seedling. It is also the process of reactivation of metabolic machinery of the seed resulting in the emergence of radicle and plumule. The seed of a vascular plant is a small package produced in a fruit or cone after the union of male and female reproductive cells. All fully developed seeds contain an embryo and, in most plant species some store of food reserves, wrapped in a seed coat. Some plants produce varying numbers of seeds that lack embryos; these are empty seeds which never germinate. Dormant seeds are viable seed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-jasmone
Jasmone is an organic compound, which is a volatile portion of the oil from jasmine flowers. It is a colorless to pale yellow liquid. Jasmone can exist in two isomeric forms with differing geometry around the pentenyl double bond, ''cis''-jasmone and ''trans''-jasmone. The natural extract contains only the cis form, while synthetic material is often a mixture of both, with the cis form predominating. Both forms have similar odors and chemical properties. Its structure was deduced by Lavoslav Ružička. Jasmone is produced by some plants by the metabolism of jasmonic acid, via a decarboxylation Decarboxylation is a chemical reaction that removes a carboxyl group and releases carbon dioxide (CO2). Usually, decarboxylation refers to a reaction of carboxylic acids, removing a carbon atom from a carbon chain. The reverse process, which is ....Paulina Dąbrowska, Wilhelm Boland "iso-OPDA: An Early Precursor of cis-Jasmone in Plants?" ChemBioChem 2007, Volume 8, pages 2281–22 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
