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. 1973 Aug;52(2):124–127. doi: 10.1104/pp.52.2.124

De Novo Synthesis of Phytochrome in Pumpkin Hooks 1

P H Quail a,2, E Schäfer a, D Marmé a
PMCID: PMC366452  PMID: 16658511

Abstract

Phytochrome becomes density labeled in the hook of pumpkin (Cucurbita pepo L.) seedlings grown in the dark on D2O, indicating that the protein moiety of the pigment is synthesized de novo during development. Red light causes a rapid decline of the total phytochrome level in the hook of etiolated seedlings but upon return to the dark, phytochrome again accumulates. These newly appearing molecules are also synthesized de novo. Newly synthesized phytochrome in both dark-grown and red-irradiated seedlings is in the red-absorbing form. Turnover of the red-absorbing form is indicated by the density labeling of phytochrome during a period when the total phytochrome level in the hook of dark-grown seedlings remains constant. However, it was not possible to determine whether this results from intracellular turnover or turnover of the whole cell population during hook growth.

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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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