title: Transient co-expression of post-transcriptional gene silencing suppressors and beta-glucuronidase in harvested lettuce leaf tissue does not improve recombinant protein accumulation in planta.
abstract: Agrobacterium-mediated gene transfer was used to co-express three virus-derived post-transcriptional gene silencing (PTGS) suppressors, P19 from tomato bushy stunt virus and two species of helper component proteinase (HcPro) from tobacco etch virus (TEV) and turnip mosaic virus, with beta-glucuronidase (GUS) in harvested lettuce leaf tissue to investigate whether GUS accumulation increases in the presence of PTGS suppressors. Co-expression incubations were 3-5 days at 4 and 22 degrees C. GUS activity and leaf viability were measured after incubation. Co-expression of PTGS suppressors did not elevate GUS expression levels. Under certain incubation conditions, co-expression of TEV HcPro significantly lowered transient GUS expression and was detrimental to leaf viability, suggesting that expression of PTGS silencers may have a negative effect on transient expression levels that outweighs any effects of PTGS suppression in harvested leaf tissues.
authors.affiliation: Department of Biological and Agricultural Engineering, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Simmons
authors.forename: Jean S
authors.initials: JS
authors.lastname: VanderGheynst
mesh_terms: D044602:Cellulases / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D016153:Genes, Suppressor / Q000502:physiology*; D018545:Lactuca / Q000502:physiology*; D018515:Plant Leaves / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000378:metabolism; D034622:RNA Interference / Q000502:physiology*; D011994:Recombinant Proteins / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; D044602:Cellulases