Sanchez L, Weidmann S, Brechenmacher L, Batoux M, Van Tuinen D, Lemanceau P, Gianinazzi S, Gianinazzi-Pearson V
UMR INRA 1088/CNRS 5184/U. Bourgogne Plante-Microbe-Environnement, INRA-CMSE, BP 86510, F-21065 Dijon cedex, France.
L. Sanchez and S. Weidmann contributed equally to this paper.
New Phytol. 2004 Mar;161(3):855-863. doi: 10.1046/j.1469-8137.2004.00997.x. Epub 2004 Jan 8.
• Beneficial rhizosphere microorganisms may share similar molecular steps during root colonization. To test this hypothesis, we compared Medicago truncatula Gaertn. gene expression in roots colonized, or not colonized, by Glomus mosseae BEG12, Pseudomonas fluorescens C7R12 or Sinorhizobium meliloti 2011. • Pseudomonas fluorescens C7R12 formed colonies on the surface of M. truncatula roots and colonized root tissues intercellularly and intracellularly in a way similar to that previously described for other plants. • Semiquantitative reverse transcriptase polymerase chain reaction of a set of 12 mycorrhiza upregulated M. truncatula genes revealed different expression profiles in roots 3 weeks after inoculation with P. fluorescens or S. meliloti. Pseudomonas fluorescens colonization activated seven of the plant genes while nodulated root systems showed increased expression in only three genes and five appeared to be downregulated. • This first report of similar gene induction by a fluorescent pseudomonad and a mycorrhizal fungus in roots supports the hypothesis that some plant cell programmes may be shared during root colonization by these beneficial microorganisms. Less similarity existed in expression of the gene set with nodulation by S. meliloti.
• 有益的根际微生物在定殖于根部的过程中可能有相似的分子步骤。为验证这一假设，我们比较了被摩西球囊霉BEG12、荧光假单胞菌C7R12或苜蓿中华根瘤菌2011定殖或未被定殖的蒺藜苜蓿根部的基因表达情况。
• 荧光假单胞菌C7R12在蒺藜苜蓿根部表面形成菌落，并以与先前描述的其他植物类似的方式在根组织细胞间和细胞内定殖。
• 对一组12个在菌根共生中上调表达的蒺藜苜蓿基因进行半定量逆转录聚合酶链反应，结果显示，在接种荧光假单胞菌或苜蓿中华根瘤菌3周后的根部，这些基因呈现出不同的表达谱。荧光假单胞菌的定殖激活了7个植物基因，而结瘤根系中只有3个基因表达增加，5个基因似乎被下调。
• 荧光假单胞菌和菌根真菌在根部诱导相似基因的这一首次报道支持了以下假设：这些有益微生物在定殖于根部的过程中可能会共享一些植物细胞程序。与苜蓿中华根瘤菌结瘤时基因集的表达相似性较低。
