Laboratorium voor Genetica, Rijksuniversiteit Gent, B-9000 Gent, Belgium.
EMBO J. 1983;2(12):2151-60. doi: 10.1002/j.1460-2075.1983.tb01716.x.
In an attempt to elucidate the transfer and integration mechanism of Agrobacterium DNA upon crown gall induction, we translocated a borderless T-DNA to different sites of the C58 Ti plasmid. As a result of the physical linkage of the T-DNA onc genes with other Ti plasmid functions, the concerned strain retained tumor-inducing capacity. However, when the borderless T-DNA is separated on an independent replicon while all other pTi functions are provided in trans, the strain can no longer induce tumors on plants. We provide evidence that the right T-DNA border region harbors one or more in cis active functions essential in the transfer and/or stabilization of the T-DNA into plant cells. The strains used in these experiments allowed us to conclude that some function(s) of the Ti plasmid can induce plant cell proliferations independently of the T-DNA transformation event. The results described here indicate that other Ti plasmid sequences than solely the T-region can be transferred to plant cells.
为了阐明根癌农杆菌 DNA 在诱导冠瘿瘤时的转移和整合机制，我们将无边界 T-DNA 转移到 C58Ti 质粒的不同位置。由于 T-DNA 致癌基因与其他 Ti 质粒功能的物理连接，相关菌株保留了诱导肿瘤的能力。然而，当无边界 T-DNA 在独立复制子上分离，而所有其他 pTi 功能都是转导提供时，该菌株就不能再在植物上诱导肿瘤。我们提供的证据表明，正确的 T-DNA 边界区域含有一个或多个顺式活性功能，对于 T-DNA 转移和/或稳定到植物细胞中是必不可少的。在这些实验中使用的菌株使我们能够得出结论，Ti 质粒的某些功能（s）可以独立于 T-DNA 转化事件诱导植物细胞增殖。这里描述的结果表明，除了 T 区之外，其他 Ti 质粒序列也可以转移到植物细胞中。
