Gibberellin

Gibberellin

Gibberellins (GAs) are plant hormones that regulate growth and influence various developmental processes, including "stem elongation , germination, dormancy, flowering, sex expression, enzyme induction and leaf and fruit senescence." [http://www.plant-hormones.info/gibberellinhistory.htm Gibberellins: A Short History] , from http://www.plant-hormones.info, the home since 2003 of a website developed by the now-closed Long Ashton Research Station]

Gibberellin was first recognized in 1926 by a Japanese scientist, Eiichi Kurosawa, studying "bakanae", the "foolish seedling" disease in rice. [ [http://www.biologie.uni-hamburg.de/b-online/e31/31d.htm Phytohormones (Plant Hormones) and other Growth Regulators: Gibberellin] , from a University of Hamburg website] It was first isolated in 1935 by Teijiro Yabuta, from fungal strains ("Gibberella fujikuroi") provided by Kurosawa. Yabuta called the isolate gibberellin.

Interest in gibberellins outside of Japan began after World War II. In the United States, the first research was undertaken by a unit at Camp Dietrick in Maryland, via studying seedlings of the bean "Vicia faba". In the United Kingdom, work on isolating new types of gibberellin was undertaken at Imperial Chemical Industries. Interest in gibberellins spread around the world as the potential for its use on various commercially important plants became more obvious. For example, research which started at the University of California, Davis in the mid-1950s led to its commercial use on Thompson seedless table grapes throughout California by 1962. [ [http://cetulare.ucdavis.edu/pubgrape/tb1400.pdf Gibberellin and Flame Seedless Grapes] from a University of California, Davis website] A known opponent to gibberellin is Paclobutrazol(PBZ), which in turn is growth inhibiting and inducing early fruitset as well as seedset.

Chemistry

Chemically, all known gibberellins are diterpenoid acids that are synthesized by the terpenoid pathway in plastids and then modified in the endoplasmic reticulum and cytosol until they reach their biologically-active form [Campbell, Neil A., and Jane B. Reece. Biology. 6th ed. San Francisco: Benjamin Cummings, 2002.] . All gibberellins are derived from the ent-gibberellane skeleton, but are synthesised via "ent"-kaurene. The gibberellins are named GA1....GAn in order of discovery. Gibberellic acid, which was the first gibberellin to be structurally characterised, is GA3.

As of 2003 there were 126 GAs identified from plants, fungi and bacteria.

Gibberellins are produced in greater mass when it’s cold. They stimulate cell elongation, breaking and budding, seedless fruits, and seed germination. They do the last by breaking the seed’s dormancy and acting as a chemical messenger. Its hormone binds to a receptor and Ca+2 activates a protein, calmodulin, and the complex binds to DNA, producing an enzyme to stimulate growth in the embryo.

References


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  • gibberellin — n. (Chem.), Any of a number plant growth hormones, the first of which was isolated in 1938 from the fungus {Gibberella fujikuroi}; more than 60 related gibberelins are known. The most important is {gibberellin A3}, also called {gibberellic acid} …   The Collaborative International Dictionary of English

  • gibberellin A3 — gibberellin gibberellin n. (Chem.), Any of a number plant growth hormones, the first of which was isolated in 1938 from the fungus {Gibberella fujikuroi}; more than 60 related gibberelins are known. The most important is {gibberellin A3}, also… …   The Collaborative International Dictionary of English

  • gibberellin — gibberellin. См. гиббереллин. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • gibberellin — [jib΄ər el′in] n. [< ModL Gibberella (dim. of L gibber, hump on the back < gibbus: see GIB1) + IN1] one of a group of organic compounds, secreted by an ascomycetous fungus (Gibberella fujikuroi), which behave like plant hormones in… …   English World dictionary

  • gibberellin A3 — gibberellic acid gibberellic acid n. (Chem.), A plant growth hormone of the gibberellin series ({C19H22O6}), also called {gibberellin A3}. It was first isolated from the fungus {Gibberella fujikuroi}. It is used to promote the growth of seedlings …   The Collaborative International Dictionary of English

  • Gibberellin — Strukturformel Allgemeines Name Gibberellinsäure Andere Namen Gibberellin A3 …   Deutsch Wikipedia

  • gibberellin — /jib euh rel in/, n. Biochem. any of a class of growth hormones occurring in fungi and plants. [1935 40; < NL Gibberell(a) (see GIBBERELLIC ACID) + IN2] * * * ▪ biochemistry       any of a group of plant hormones that occur in seeds, young leaves …   Universalium

  • Gibberellin — Gib|be|rel|lin [nlat. Gibberella fujikuroi, ein reisschädigender Pilz (Mikrobiol.); ↑ in (3)], das; s, e: Gruppenbez. für natürliche tetra u. pentacycl. Diterpenoide, die als hormonartig wirkende ↑ Pflanzenwuchsstoffe insbes. das Längenwachstum… …   Universal-Lexikon

  • gibberellin — giberelinas statusas T sritis chemija apibrėžtis Augalų hormonas. atitikmenys: angl. gibberellin rus. гиббереллин …   Chemijos terminų aiškinamasis žodynas

  • gibberellin — giberelinas statusas T sritis augalininkystė apibrėžtis Augalų hormonas, sukeliantis arba aktyvinantis augalų augimą. atitikmenys: angl. gibberellin rus. гиббереллин …   Žemės ūkio augalų selekcijos ir sėklininkystės terminų žodynas

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