title: Regulation of swelling of etiolated-wheat-leaf protoplasts by phytochrome and gibberellic acid.
abstract: The effect of light on the size of intact protoplasts isolated from the primary leaves of etiolated Triticum aestivum was studied. A 2-min red-light irradiation in the presence of 1 mM KCl was sufficient to cause a swelling of protoplasts compared with those maintained in darkness. The effect was photoreversible by far-red light over two light cycles, indicating the involvement of phytochrome. At 4°C, escape from reversibility occurred between 2 and 5 min after the exposure to red light. In exposure-response experiments, 20 s red light at 27 μmol m(-2)s(-1) was sufficient to saturate the response. Exogenous gibberellic acid added in darkness in the presence of KCl also induced protoplast swelling. Gibberellins may act as an intermediate in the phytochrome-induced swelling of protoplasts.
authors.affiliation: School of Biological Sciences, University of Sussex, Falmer, BN1 9QG, Brighton, Sussex, UK.
authors.forename: S D
authors.initials: SD
authors.lastname: Blakeley
authors.forename: B
authors.initials: B
authors.lastname: Thomas
authors.forename: J L
authors.initials: JL
authors.lastname: Hall
authors.forename: D
authors.initials: D
authors.lastname: Vince-Prue