ISSN:
1432-2048
Keywords:
Auxin receptor
;
Cucurbita (auxin action)
;
Growth
;
Phospholipase A in auxin action
;
Signal transduction
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Microsomal vesicles were prepared from zucchini (Cucurbita pepo L.) hypocotyls containing radioactive phosphatidylethanolamine or phosphatidylcholine, and these lipids were used as substrates by phospholipase A which is activated by auxins. Phospholipase D and phospholipase C hydrolysed the same substrates but were not influenced by auxin. Phospholipase A was activated by the auxins indolyl-3-acetic acid, 2,4-dichlorophenoxyacetic acid and, to a lesser extent, by α-naphthaleneacetic acid whereas the weak auxins 2,3-dichlorophenoxyacetic acid and β-naphthaleneacetic acid were almost inactive. This hormone specificity was also found in growth tests with etiolated zucchini hypocotyls. Phospholipase A activation by auxin was blocked by a polyclonal antibody against the maize auxin-binding protein. We propose that phospholipase A activation is a primary reaction in the signal transduction leading from hormone-binding to the growth response.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00194062
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