Gatz C, Quail P H
Department of Botany, University of Wisconsin, Madison 53706.
Proc Natl Acad Sci U S A. 1988 Mar;85(5):1394-7. doi: 10.1073/pnas.85.5.1394.
The Tn10-encoded tet repressor-operator system was used to regulate transcription from the cauliflower mosaic virus (CaMV) 35S promoter. Expression was monitored in a transient assay system by using electric field-mediated gene transfer ("electroporation") into tobacco protoplasts. The tet repressor, being expressed in the plant cells under the control of eukaryotic transcription signals, blocks transcription of a CaMV 35S promoter chloramphenicol acetyltransferase (cat) fusion gene when the two tet operators flank the "TATA" box. In the presence of the inducer tetracycline, expression is restored to full activity. Location of the operators 21 base pairs downstream of the transcription start site does not significantly affect transcription in the presence of the repressor. These experiments show that a prokaryotic regulatory protein can function in plant cells. The tet repressor-operator complex may be useful for specifically inducing transferred genes at different stages of plant development.
Tn10编码的四环素阻遏蛋白-操纵子系统被用于调控来自花椰菜花叶病毒（CaMV）35S启动子的转录。通过电场介导的基因转移（“电穿孔”）将其导入烟草原生质体，在瞬时分析系统中监测表达情况。四环素阻遏蛋白在真核转录信号的控制下在植物细胞中表达，当两个四环素操纵子位于“TATA”框两侧时，它会阻断CaMV 35S启动子氯霉素乙酰转移酶（cat）融合基因的转录。在诱导剂四环素存在的情况下，表达恢复到完全活性状态。操纵子位于转录起始位点下游21个碱基对处，在阻遏蛋白存在时对转录没有显著影响。这些实验表明，一种原核调节蛋白可以在植物细胞中发挥作用。四环素阻遏蛋白-操纵子复合物可能有助于在植物发育的不同阶段特异性诱导转移基因。
