Hostname: page-component-cc8bf7c57-5wl6q Total loading time: 0 Render date: 2024-12-12T01:50:25.905Z Has data issue: false hasContentIssue false

Protein and Nucleic Acid Syntheses in Dark-dormant Common Purslane (Portulaca oleracea) Seed

Published online by Cambridge University Press:  12 June 2017

Bonnie J. Reger
Affiliation:
Russell Res. Center, Sci. Ed. Admin., U.S. Dep. Agric, Athens, GA 30604
Ida E. Yates
Affiliation:
Russell Res. Center, Sci. Ed. Admin., U.S. Dep. Agric, Athens, GA 30604

Abstract

Dark-incubated common purslane (Portulaca oleracea L.) seed synthesize very little protein and essentially no nucleic acids. Dark-incubated seed incorporate only 14 × 10−3 nmoles 14C-leucine/mg protein/12-h dark. In contrast, seed exposed to 12-h light following 24-h dark incubation incorporate 365 × 10−3-nmoles 14C-leucine/mg protein/12-h light. Once dormancy is broken by exposure of seed to light, initiation of radicle protrusion occurs at 12 h. Protein synthesis gradually increases with time in the light and precedes nucleic acid synthesis which is associated with radicle protrusion. During the 12-h lag period preceding radicle protrusion protein synthesis increases significantly by 3 to 9 h in light, RNA synthesis by 9 h in light, and DNA synthesis by 12 h in light. After 12 h in light, 32P can be detected in all nucleic acid fractions, DNA and RNAs.

Type
Research Article
Copyright
Copyright © 1978 by the Weed Science Society of America 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Literature Cited

1. Cross, H. 1931. Laboratory germination of weed seeds. Assoc. Official Seed Anal. North Am. Proc. 24:125128.Google Scholar
2. Egley, G. H. 1974. Dormancy variations in common purslane seeds. Weed Sci. 22:535540.CrossRefGoogle Scholar
3. Fountain, D. W. and Bewley, J. D. 1973. Polysome formation and protein synthesis in imbibed but dormant lettuce seeds. Plant Physiol. 52:604607.CrossRefGoogle ScholarPubMed
4. Frankland, B., Jarvis, B. C., and Cherry, J. H. 1971. RNA synthesis and the germination of light-sensitive lettuce seeds. Planta 97:3949.Google Scholar
5. Hoagland, R. E. 1977. Proteolytic enzymes in dormant and germinating common purslane seeds. Proc. South. Weed Sci. Soc. 30:365.Google Scholar
6. Leaver, C. J. and Key, J. L. 1970. Ribosomal RNA synthesis in plants. J. Mol. Biol. 49:671680.CrossRefGoogle ScholarPubMed
7. Loening, U. E. 1969. The determination of the molecular weight of ribonucleic acid by polyacrylamide gel electrophoresis. Biochemistry 113:131138.Google Scholar
8. Lowry, O. H., Rosenbrough, N. J., Farr, A. L., and Randall, R. J. 1951. Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193:265275.CrossRefGoogle ScholarPubMed
9. Mitchell, R. C. and Villiers, T. A. 1972. Polysome formation in light-controlled dormancy. Plant Physiol. 50:671674.Google Scholar
10. Reger, B. J. 1976. UV-C surface-sterilization of common purslane seed. Plant Physiol. 57 (Supplement):9.Google Scholar
11. Reger, B. J., Egley, G. H., and Swanson, C. R. 1975. Polysome formation in light-sensitive common purslane seeds. Plant Physiol. 55:928931.Google Scholar
12. Singh, K. P. 1973. Effect of temperature and light on seed germination of two ecotypes of Portulaca oleracea L. New Phytol. 72:289295.CrossRefGoogle Scholar