Vijn I, Martinez-Abarca F, Yang W C, das Neves L, van Brussel A, van Kammen A, Bisseling T
Department of Molecular Biology, Agricultural University, Wageningen, The Netherlands.
Plant J. 1995 Jul;8(1):111-9. doi: 10.1046/j.1365-313x.1995.08010111.x.
Rhizobium leguminosarum bv. viciae-secreted Nod factors are able to induce root hair deformation, the formation of nodule primordia and the expression of early nodulin genes in Vicia sativa (vetch). To obtain more insight into the mode of action of Nod factors the expression of early nodulin genes was followed during Nod factor-induced root hair deformation and nodule primordium formation. The results of these studies suggested that the expression of VsENOD5 and VsENOD12 is not required for root hair deformation. In the Nod factor-induced primordia both VsENOD12 and VsENOD40 are expressed in a spatially controlled manner similar to that found in Rhizobium-induced nodule primordia. In contrast, VsENOD5 expression has never been observed in Nod factor-induced primordia, showing that the induction of VsENOD5 and VsENOD12 expression are not coupled. VsENOD5 expression is induced in the root epidermis by Nod factors and in Rhizobium-induced nodule primordia only in cells infected by the bacteria, suggesting that the Nod factor does not reach the inner cortical cells.
豌豆根瘤菌蚕豆生物变种分泌的结瘤因子能够诱导箭筈豌豆（巢菜）的根毛变形、根瘤原基的形成以及早期结瘤素基因的表达。为了更深入了解结瘤因子的作用模式，在结瘤因子诱导根毛变形和根瘤原基形成过程中，对早期结瘤素基因的表达进行了跟踪研究。这些研究结果表明，根毛变形不需要VsENOD5和VsENOD12的表达。在结瘤因子诱导的原基中，VsENOD12和VsENOD40均以空间控制的方式表达，类似于在根瘤菌诱导的根瘤原基中发现的表达方式。相比之下，在结瘤因子诱导的原基中从未观察到VsENOD5的表达，这表明VsENOD5和VsENOD12表达的诱导并非相互关联。结瘤因子在根表皮中诱导VsENOD5表达，而在根瘤菌诱导的根瘤原基中，仅在被细菌感染的细胞中诱导其表达，这表明结瘤因子无法到达内皮层细胞。
