Submitted to: American Association of Cereal Chemists Meetings
Publication Type: Abstract Only
Publication Acceptance Date: 9/19/2004
Publication Date: 9/19/2004
Citation: Jia, H., Nettleton, D., Scott, M.P. 2004. Transcript levels and zein content of transgenic maize expressing the wheat glu-dx5 transgene. American Association of Cereal Chemists Meetings. Abstract No. 192.
Technical Abstract: In wheat, the high molecular weight (HMW) glutenins are important determinants of dough elasticity. It may be possible to impart new physical properties on maize flour by transferring wheat storage protein genes to maize. To test this hypothesis, we developed transgenic maize lines that contain the wheat HMW glutenin gene Glu1-Dx5. This gene functions to produce the 1Dx5 HMW glutenin subunit in maize endosperm to about 2% of the total protein. The objective of this study was to characterize the impact of this transgene on expression of the native seed storage proteins and global transcript levels of maize endosperm. We evaluated immature kernels from two transformation events. Transgene positive and negative kernels produced on the same ear were compared. In one event, zein and total nitrogen levels were higher in positive kernels, while in the other event they were lower. Transcript profiling with cDNA micro arrays indicated that only one transcript out of about 6000 was significantly differentially expressed in one event and that only 25 transcripts were differentially expressed in the other. These 25 transcripts included two alpha zein transcripts, consistent with the results of zein analysis. Taken together, these results suggest that the wheat 1Dx5 HMW glutenin subunit can accumulate to high levels in maize with relatively minor impact on native gene expression and protein accumulation.