In Vitro Promotion by Auxins of Divalent Ion Release from Soybean Membranes
Year: 1981
Type: article
Abstract: Release of divalent ions from membrane pellets of soybean hypocotyls was promoted by the natural auxin, indole-3-acetic acid, and the synthetic auxin, 2,4-dichlorophenoxyacetic acid. The calcium release occurred at auxin concentrations as low as 1 nanomolar, and maximum release was observed at 1 micromolar. Hormone concentrations greater than 1 micromolar showed reduced effectiveness in releasing membrane-associated calcium. 2,3-Dichlorophenoxyacetic acid, a weak-auxin analog of 2,4-dichlorophenoxyacetic acid, did not promote calcium release. In some experiments, the analog actually promoted calcium association with the membranes. Red blood cells treated in a similar manner to soybean hypocotyl membranes did not release calcium in response to indole-3-acetic acid. The release phenomenon was hormone specific but not ion specific. Auxin released manganese from membranes in a manner similar to that of calcium. The calcium release, following auxin treatment, is accompanied by a decrease in membrane-associated sites for calcium binding.
Source: PLANT PHYSIOLOGY
DOI: 10.1104/pp.68.2.512
Institution: Purdue University West Lafayette
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W2051706604