Transient Gene-Expression In Electroporated Protoplasts Of Eucalyptus-Citriodora Hook

Protoplasts isolated from cotyledons of Eucalyptus citriodora were electroporated using a rectangular pulse, with plasmid carrying the cat gene. The levels of transient expression and protoplast viability were influenced by the voltage and pulse duration. At a field strength of 800 V cm-1 (1000-mu-s), a protoplast viability of 57%, and 47% conversion of C-14-chloramphenicol to its acetylated forms, were obtained. Expression levels were improved by an increase in plasmid concentration (up to 60-mu-g ml-1), and also by the addition of carrier DNA. Gene expression was further enhanced by the addition of 40% (w/v) PEG, in the presence of the carrier DNA, to the protoplasts after electroporation.