Enhanced transgene expression by co-expression with a suppressor of post-transcriptional gene silencing (ptgs)

Abstract

Disclosed are a variety of methods for achieving enhanced expression from a target nucleotide sequence in a plant e.g. comprising the step of transiently introducing into a tissue of a plant (e.g. a leaf) a first nucleic acid comprising the target nucleotide sequence and a second nucleic acid encoding a Post Transcriptional Gene Silencing (PTGS) suppressor protein (preferably of viral or plant origin), wherein the first and second nucleic acids are comprised within a single binary vector construct, or the first and second nucleic acid sequences are comprised within a first binary vector and a second binary vector construct respectively. The plant tissue may then be harvested for the protein. Such methods can give much higher levels of gene expression than are obtainable using stable transgenes, or certain replicating vectors. Also disclosed are specific PTGS suppressor proteins: potato virus X (pvx) p25 protein; african cassava mosaic virus (acmv) AC2 protein; rice yellow mottle virus (rymv) P1 protein; tomato bushy stunt virus (tbsv) 19K protein; plus variants of these. These suppressors may be used in any PTRS context, including the enhancement of transient expression systems.