Skip to main content
PMC home page
Plant Physiology logoLink to Plant Physiology
. 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.

Full text

PDF
124

Selected References

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

  1. BUTLER W. L., NORRIS K. H. The spectrophotometry of dense light-scattering material. Arch Biochem Biophys. 1960 Mar;87:31–40. doi: 10.1016/0003-9861(60)90119-3. [DOI] [PubMed] [Google Scholar]
  2. Clarkson D. T., Hillman W. S. Stable concentrations of phytochrome in pisum under continuous illumination with red light. Plant Physiol. 1968 Jan;43(1):88–92. doi: 10.1104/pp.43.1.88. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Correll D. L., Edwards J. L., Klein W. H., Shropshire W., Jr Phytochrome in etiolated annual rye. 3. Isolation of photoreversible phytochrome. Biochim Biophys Acta. 1968 Sep 10;168(1):36–45. doi: 10.1016/0005-2795(68)90231-6. [DOI] [PubMed] [Google Scholar]
  4. Filner P., Varner J. E. A test for de novo synthesis of enzymes: density labeling with H2O18 of barley alpha-amylase induced by gibberellic acid. Proc Natl Acad Sci U S A. 1967 Oct;58(4):1520–1526. doi: 10.1073/pnas.58.4.1520. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. HU A. S., BOCK R. M., HALVORSON H. O. Separation of labeled from unlabeled proteins by equilibrium density gradient sedimentation. Anal Biochem. 1962 Dec;4:489–504. doi: 10.1016/0003-2697(62)90129-x. [DOI] [PubMed] [Google Scholar]
  6. Quail P. H., Scandalios J. G. Turnover of genetically defined catalase isozymes in maize. Proc Natl Acad Sci U S A. 1971 Jul;68(7):1402–1406. doi: 10.1073/pnas.68.7.1402. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Quail P. H., Schäfer E., Marmé D. Turnover of phytochrome in pumpkin cotyledons. Plant Physiol. 1973 Aug;52(2):128–131. doi: 10.1104/pp.52.2.128. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Rubinstein B. Characteristics of hook formation by bean seedlings. Plant Physiol. 1972 Apr;49(4):640–643. doi: 10.1104/pp.49.4.640. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Rubinstein B. The Role of Various Regions of the Bean Hypocotyl on Red Light-induced Hook Opening. Plant Physiol. 1971 Aug;48(2):183–186. doi: 10.1104/pp.48.2.183. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Plant Physiology are provided here courtesy of Oxford University Press

RESOURCES