A wheat genomic DNA fragment reduces pollen transmission of maize transgenes by reducing pollen viability.

A genomic DNA fragment from wheat carrying the Glu-1Dx5 gene has been shown to exhibit reduced pollen transmission in transgenic maize. To localize the region of the DNA fragment responsible for this reduced pollen transmission, we produced transgenic maize plants in which the wheat genomic DNA proximal to the 1Dx5 coding sequence was replaced with the maize 27 kDa gamma-zein promoter. Like the wheat promoter-driven Glu-1Dx5 transgene, this zein promoter-driven transgene functioned to produce 1Dx5 in maize endosperm.