Aptamers Improve the Expression of a Human Granulocyte-Macrophage Colony Stimulating Factor in Transgenic Arabidopsis thaliana Seeds

摘要

Domain IV nucleotides of human 7SL RNA comprise an approximately 50-nucleotide region with a highly conserved secondary structure consisting of two internal loops. We inserted these into a modified 3'-untranslated region of the human granulo-cyte-macrophage colony stimulating factor (hGM-CSF) gene. The expression vector, under the control of a tissue-specific promoter derived from the soybean a' subunit of f3-conglycinin, was introduced into Arabidopsis thaliana by Agrobacterium-mediated transformation. Expression of the recombinant hGM-CSF significantly improved, accounting for as much as 0.049% of the total soluble protein in the Arabidopsis siliques. Western blots showed that the molecular weight of this recombinant hGM-CSF was approximately 21 kD. In addition, TF-1 cell proliferation data demonstrated that the recombinant hGM-CSF was biologically active. Our results provide evidence that aptamers can strongly enhance gene expression.