Movement of DNA across the chloroplast envelope: Implications for the transfer of promiscuous DNA

Authors

Heriberto D. Cerutti, University of Nebraska - LincolnFollow
André Jagendorf, Cornell University

Date of this Version

April 1995

Comments

Published in Photosynthesis Research 46 (1995), pp. 329–337. Copyright © 1995 Kluwer Academic Publishers. Used by permission. http://www.springerlink.com/content/0166-8595

Abstract

Little is known about the mechanistic basis for the movement of promiscuous nucleic acids across cell membranes. To address this problem we sought conditions that would permit the entry of plasmid DNA into isolated, intact pea chloroplasts. DNA uptake did not occur normally, but was induced by hypotonic treatments, by incubation with millimolar levels of Mg²⁺, or by heat shock at 42 °C. These results are consistent with DNA movement being permitted by conditions that transiently alter the permeability of the chloroplast envelope. Plant cells are subject to osmotic tensions and/or conditions inducing polymorphic changes in the membranes, such as those used in the present study, under several environmental stresses. In an evolutionary time frame, these phenomena may provide a mechanism for the transfer of promiscuous nucleic acids between organelles.