Differences in cell type-specific expression of the gene Opaque 2 in maize and transgenic tobacco.

摘要: The Opaque 2 (O2) gene encodes a transcriptional activator of the basic region/leucine zipper family, which controls synthesis major storage protein class in maize endosperm, 22 kDa α-zeins, and several other non-zein polypeptides including b32. We demonstrate, by analysing O2 mRNAs different organs plants, that is only active endosperm. Its transcription precisely controlled during seed development: are first detected 10 days after pollination accumulate endosperm over period 20 days. When introduced into tobacco promoter directs expression β-glucuronidase (GUS) reporter but also embryo, cotyledons pollen. 185 sufficient for developmentally regulated seeds. A distinct cis-acting element, located between positions −185 −520, seedlings. possible origins this breakdown specificity heterologous host discussed.