Transcription from maize storage protein gene promoters in yeast

Genes coding for zein storage proteins of maize of the 19 000- and 21 000-dalton size classes were integrated into chromosome II of the yeast Saccharomyces cerevisiae. Using the transformed yeast strains as an in vivo transcription system it was shown that promoter regions of the zein genes of both size classes were accurately recognized. In particular, the zein mRNA synthesis in yeast starts at the same nucleotide positions used in the maize endosperm. A difference in the promoter activity between the 21 000- and the 19 000-dalton zein genes was observed.