Premium
Mise en évidence de I'AIA‐5‐ 3 H par autoradiographie dans le coléoptile de Blé
Author(s) -
Perbal Gérald,
Leroux Yves,
DrissEcole Dominique
Publication year - 1982
Publication title -
physiologia plantarum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.351
H-Index - 146
eISSN - 1399-3054
pISSN - 0031-9317
DOI - 10.1111/j.1399-3054.1982.tb06321.x
Subject(s) - glutaraldehyde , auxin , protoplasm , cell wall , biophysics , chemistry , biology , microbiology and biotechnology , biochemistry , botany , cytoplasm , chromatography , gene
Two methods of fixation of 3 H‐IAA on macromolecules were studied in order to obtain autoradiographs of semi‐thin sections after a routine treatment for electron microscopy. Glutaraldehyde and DCC [1‐(3‐dimethylaminopropyl)‐3‐ethylcarbodiimide hydrochloride] could be used to obtain in vitro fixation of auxin on proteins. However, the rate of reaction with DCC was greater, so that the method using this compound is preferable. A cytological study was performed on wheat coleoptiles ( Triticum sativum L., var. Capitole) after application of 3 H‐IAA to their tips. Almost no radioactivity was found in the phloem elements while the procambium and the vessels were intensively labelled. In parenchyma cells, cell walls, nuclei and intercellular spaces contained a large amount of 3 H‐IAA. These results are consistent with the hypothesis that auxin is transported, from cell to cell, via the apoplast. The extraction of auxin by methanol before cytological fixation indicates that this hormone is not bound (by a covalent binding) to cellular structures, except perhaps in the secondary wall of vessels.