OPTIMIZING EXPRESSION OF TRANSGENES WITH AN EMPHASIS ON POSTTRANSCRIPTIONAL EVENTS

Introducing a foreign gene into a new plant host does not always resul t in a high level of expression of the incoming gene. Numerous promote rs have been used to express foreign genes in different plant tissues, but there are sometime various features of the new gene which are del eterious to expression in the new host. There are a number of posttran scriptional steps in the expression of a gene and sometimes sequences present in a particular coding region can resemble the signals which i nitiate these processing steps. When aberrantly carried out, these ste ps diminish the level of expression. By removing such fortuitous signa ls, one can dramatically increase expression of a transgene in plants. Ensuring proper protein folding and/or targeting the protein product to a particular cellular compartment can also be used to increase the level of protein obtained. The various methods used to optimize expres sion of a foreign gene in plants by concentrating on post-transcriptio nal events an discussed.