Elmayan T, Tepfer M
Laboratoire de Biologie Cellulaire, INRA-Versailles, France.
Transgenic Res. 1995 Nov;4(6):388-96. doi: 10.1007/BF01973757.
In order to study the expression in plants of the rolD promoter of Agrobacterium rhizogenes, we have constructed chimaeric genes placing the coding region of the gusA (uidA) marker gene under control of two rolD promoter fragments of different length. Similar results were obtained with both genes. Expression studies were carried out in transformed R1 progeny plants. In mature transformed tobacco plants, the rolD-gus genes were expressed strongly in roots, and to much lower levels in stems and leaves. This pattern of expression was transmitted to progeny, though the ratio of the level of expression in roots relative to that in leaves was much lower in young seedlings. The degree of root specificity in rolD-gus transformants was less than that of a gene constructed with domain A of the CaMV 35S promoter, domA-gus, but the level of root expression was much higher than with the latter gene. However, the level of expression of the rolD-gus genes was less than that of a gus gene with a 35S promoter with doubled domain B, 35S2-gus. The rolD-gus genes had a distinctive pattern of expression in roots, compared to that of the two other genes, with the strongest GUS activity observed in the root elongation zone and in vascular tissue, and much less in the root apex.
为了研究发根农杆菌rolD启动子在植物中的表达情况，我们构建了嵌合基因，将gusA（uidA）标记基因的编码区置于两个不同长度的rolD启动子片段的控制之下。两个基因都获得了相似的结果。在转化的R1后代植株中进行了表达研究。在成熟的转化烟草植株中，rolD - gus基因在根中强烈表达，而在茎和叶中的表达水平要低得多。这种表达模式传递给了后代，不过在幼苗中根中表达水平与叶中表达水平的比值要低得多。rolD - gus转化体中的根特异性程度低于用花椰菜花叶病毒35S启动子的A结构域构建的基因domA - gus，但根中的表达水平远高于后者。然而，rolD - gus基因的表达水平低于具有双倍B结构域的35S启动子的gus基因35S2 - gus。与另外两个基因相比，rolD - gus基因在根中有独特的表达模式，在根伸长区和维管组织中观察到最强的GUS活性，而在根尖中则少得多。
