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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1970 Jan;65(1):51–57. doi: 10.1073/pnas.65.1.51

Phytochrome-Mediated Repression of Enzyme Synthesis (Lipoxygenase): A Threshold Phenomenon*

H Oelze- Karow 1, P Schopfer 1, H Mohr 1
PMCID: PMC286189  PMID: 5263762

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.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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