Giovinazzo G, Manzocchi L A, Bianchi M W, Coraggio I, Viotti A
Istituto Biosintesi Vegetali CNR, Milano, Italy.
Plant Mol Biol. 1992 May;19(2):257-63. doi: 10.1007/BF00027347.
The transcription of zein genes in maize is tissue-specific and developmentally regulated. The 5' regulatory region of many zein genes contains two promoters, P1 and P2, lying approximately 1000 bases apart. The promoter/enhancer activity of various fragments of the two promoter regions of the zein gene E19 have been analysed by means of transient expression experiments. The results indicate that the various regions differentially affect the expression of the GUS reporter gene activity in protoplasts from tobacco leaves, maize immature endosperms and in vitro endosperm cell cultures. In tobacco protoplasts only the proximal promoter region, P2, activates GUS expression, while in endosperm culture cells only the distant promoter, P1, gives significant activity. The P1 region, both in direct and opposite orientation, stimulates a low level of GUS expression in protoplasts from immature endosperms.
玉米中醇溶蛋白基因的转录具有组织特异性并受发育调控。许多醇溶蛋白基因的5'调控区含有两个启动子，P1和P2，它们相距约1000个碱基。通过瞬时表达实验分析了醇溶蛋白基因E19两个启动子区域的不同片段的启动子/增强子活性。结果表明，不同区域对烟草叶片原生质体、玉米未成熟胚乳和体外胚乳细胞培养物中GUS报告基因活性的表达有不同影响。在烟草原生质体中，只有近端启动子区域P2激活GUS表达，而在胚乳培养细胞中，只有远端启动子P1具有显著活性。P1区域无论正向还是反向，都能刺激未成熟胚乳原生质体中低水平的GUS表达。
