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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 

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