Abstract
Commercial cultivars of Bollgard® cotton, Gossypium hirsutum L., differ in the amount of expressed Cry1Ac protein. However, the plant-mechanism for which this occurs is still unknown. Using quantitative real-time polymerase chain reaction (qPCR), we developed a method to determine if differences in the overall level of Cry1Ac among Bollgard® lines could be correlated to the mRNA transcripts. Our data shows that the cry1Ac mRNA transcript differs among Bollgard® lines and are correlated with corresponding Cry1Ac protein levels. In addition, qPCR based methods can efficiently be employed to quantify Cry1Ac protein expression levels in transgenic cotton cultivars. We postulate that qPCR based methods could be successfully employed for quantifying expression levels of transgenes in plants carrying different Bt toxins.
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Acknowledgements
We thank the numerous student aids that assisted in collecting cotton tissue for analysis. Statistical assistance by Debbie Boykin, USDA, ARS, Mid-South Area, is much appreciated. Comments and suggestions were much appreciated from Drs. Kate Aronstein, Jesus DeLeon, Bill Pettigrew, and Jack McCarty. Mention of a trademark, warranty, proprietary product or vendor does not constitute a guarantee by the USDA and does not imply approval or recommendation of the product to the exclusion of others that may be suitable.
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Adamczyk, J.J., Perera, O. & Meredith, W.R. Production of mRNA from the cry1Ac transgene differs among Bollgard® lines which correlates to the level of subsequent protein. Transgenic Res 18, 143–149 (2009). https://doi.org/10.1007/s11248-008-9198-z
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DOI: https://doi.org/10.1007/s11248-008-9198-z