Abstract
The utility of green fluorescent protein (GFP) for biological research is evident. A fluorescence-based method was developed to quantify GFP levels in transgenic plants and protein extracts. Fluorescence intensity was linear with increasing levels of GFP over a range that encompasses transgene expression in plants by the cauliflower mosaic virus 35S promoter. Standard curves were used to estimate GFP concentration in planta and in protein extracts. These values were consistent with ELISA measurements of GFP in protein extracts from transgenic plants, indicating that the technique is a reliable measure of recombinant GFP expression. The levels of in planta GFP expression in both homozygous and hemizygous plants was then estimated. Homozygous transgenic plants expressed twice the amount of GFP than hemizygous plants, suggesting additive transgene expression. This methodology may be useful to simplify the characterization of transgene expression in plants.
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Abbreviations
- ELISA :
-
Enzyme-linked immunosorbent assay
- HRP :
-
Horseradish peroxidase
- GFP :
-
Green fluorescent protein
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Acknowledgements
We wish to thank Bill Ward (Rutgers University) for the kind gift of the recombinant GFP and Jim Haseloff (Cambridge University) for the pBin mGFP5-ER plasmid. Funding was provided by grants to CNS from the USDA.
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Communicated by M.C. Jordan
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Richards, H.A., Halfhill, M.D., Millwood, R.J. et al. Quantitative GFP fluorescence as an indicator of recombinant protein synthesis in transgenic plants. Plant Cell Rep 22, 117–121 (2003). https://doi.org/10.1007/s00299-003-0638-1
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DOI: https://doi.org/10.1007/s00299-003-0638-1