(Redirected from Gibberellins)

GA1

''ent''-Gibberellane

''ent''-Kauren
'Gibberellins' (GAs) are
plant hormones involved in promotion of
stem elongation, mobilization of
food reserves in
seeds and other
processes. Its absence results in the
dwarfism of some plant varieties. 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
[1]. All gibberellins are derived from the ent-gibberellane skeleton, but are synthesised via ''ent''-kauren. The gibberellins are named GA1....GAn in order of discovery.
Gibberellic acid, which was the first gibberellin to be structurally characterised, is GA3. There are currently 136 GAs identified from plants, fungi and bacteria.
Much of our knowledge of the biosynthesis and molecular mechanisms of gibberellins comes from research on their role in triggering α-amylase release by the aleurone layer in seed germination. Gibberellin was first isolated in
1935 by
Japanese
scientist,
Teijiro Yabuta (
1888-
1977) from the fungus ''
Gibberella fujikuroi''.
References
1. Cambell, Neil A., and Jane B. Reece. Biology. 6th ed. San Francisco: Benjamin Cummings, 2002.
External links
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Phytohormones (Plant Hormones) and other Growth Regularors: Gibberellin