Abstract
Synthesis of the enzyme lipoxygenase in the cotyledons of the mustard seedling (Sinapis alba L.) is controlled by phytochrome (Pfr) through a threshold mechanism. The repression of enzyme synthesis by Pfr is a very rapid process after the threshold level is surpassed. Similarly, enzyme synthesis starts instantaneously and with full speed as soon as the Pfr level decreases below the threshold level. Thus Pfr rapidly inhibits synthesis of an enzyme and functions through an all-or-none control mechanism of high precision.
Full text
PDF






Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Hendricks S. B., Borthwick H. A. The function of phytochrome in regulation of plant growth. Proc Natl Acad Sci U S A. 1967 Nov;58(5):2125–2130. doi: 10.1073/pnas.58.5.2125. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Surrey K. Action and interaction of red and far-red radiation on lipoxidase metabolism of squash seedlings. Plant Physiol. 1967 Mar;42(3):421–424. doi: 10.1104/pp.42.3.421. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Surrey K., Barr E. M. Light-dependent modifications in the metabolic responses of squash seedlings. Plant Physiol. 1966 May;41(5):780–786. doi: 10.1104/pp.41.5.780. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Surrey K. Spectrophotometric Method for Determination of Lipoxidase Activity. Plant Physiol. 1964 Jan;39(1):65–70. doi: 10.1104/pp.39.1.65. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Withrow R. B., Klein W. H., Elstad V. Action Spectra of Photomorphogenic Induction and Its Photoinactivation. Plant Physiol. 1957 Sep;32(5):453–462. doi: 10.1104/pp.32.5.453. [DOI] [PMC free article] [PubMed] [Google Scholar]