Studies on the effects of steroidal estrogens in the dwarf French bean, Phaseolus vulgaris L. cv. Canadian Wonder

Stewart, Catriona Anne (1987) Studies on the effects of steroidal estrogens in the dwarf French bean, Phaseolus vulgaris L. cv. Canadian Wonder. MSc(R) thesis, University of Glasgow.

Abstract

In this thesis various aspects of the physiology and biochemistry of steroidal estrogens in Phaseolus vulgaris have been studied in an attempt to achieve some understanding of the mode of action of these steroid hormones in plants. Three main lines of investigation were followed. Firstly, the effects of estrone-sulphate and estradiol-sulphate on root initiation were examined in primary leaf cuttings. Confirmation was obtained that application of estrogen-sulphate conjugates, by wick feeding, significantly reduces adventitious root formation. This effect was manifest after six days treatment and was consistently more pronounced with application of estradiol-sulphate. Microscopical examination of the petioles of primary leaf cuttings and the bases of hypocotyl cuttings treated with estrone-sulphate and estradiol-sulphate confirmed the induction of anomalous cell development in the vascular tissues and in the areas normally associated with adventitious root production. These zones of anomalous cell development could first be observed five days after commencement of estrogen treatment. Secondly, the uptake and distribution of exogenous estrogens by hypocotyl cuttings and by primary leaf cuttings was examined using 14C labelled estrone and estradiol. Estrone and estradiol behaved physiologically in the same way. Uptake of radioactivity by hypocotyl cuttings appeared to be, to some degree, selective, but uptake by primary leaf cuttings was apparently passive. The subsequent distribution of radioactivity in both hypocotyl and primary leaf cuttings was very restricted, and to a great extent remained unaltered during the treatment periods employed. These results are considered in the light of previous work on the metabolism of steroidal estrogens in Phaseolus vulgaris. Thirdly, the effects of estrogen-sulphates on root initiation and cell development in primary leaf cuttings were used as the basis of an experimental system for investigating the mode of action of estrogens in plants at the molecular level. An in vitro protein synthesising system derived from wheat germ was used to translate Poly (A)+RNA prepared from the petioles of estrogen-treated and control cuttings. The separated polypeptide products of translation were compared but, at the level of resolution employed, it appears that estrogen treatment does not induce either quantitative or qualitative changes in the mRNA populations of the responding tissue.

• Item Type: Thesis (MSc(R))
• Qualification Level: Masters
• Keywords: Botany, Plant sciences
• Date of Award: 1987
• Depositing User: Enlighten Team
• Unique ID: glathesis:1987-76640
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 19 Nov 2019 13:59
• Last Modified: 19 Nov 2019 13:59
• URI: https://theses.gla.ac.uk/id/eprint/76640