The mobility of the tobacco Tnt1 retrotransposon correlates with its transcriptional activation by fungal factors

51 ref.International audienc

The mobility of the tobacco Tnt1 retrotransposon correlates with its transcriptional activation by fungal factors

51 ref.International audienc

Distribution dynamics of the Tnt1 retrotransposon in tobacco

International audienc

Tavelure du pommier sa résistance aux strobilurines en France - Tests biologiques et moléculaires 2004-2006

National audienceDans la lutte chimique contre la tavelure, il est essentiel de savoir si l'agent de la maladie présente une résistance à certains des fongicides utilisés. D'où la surveillance évoquée dans cet articl

The pentose catabolic pathway of the rice-blast fungus Magnaporthe oryzae involves a novel pentose reductase restricted to few fungal species

International audienc

The auxin-inducible GH3 homologue Pp-GH3.16 is downregulated in Pinus pinaster root systems on ectomycorrhizal symbiosis establishment

• In an attempt to determine whether auxin-regulated plant genes play a role in ectomycorrhizal symbiosis establishment, we screened a Pinus pinaster root cDNA library for auxin-upregulated genes. This allowed the identification of a cDNA, Pp-GH3.16 , which encodes a polypeptide sharing extensive homologies with GH3 proteins of different plants. • Pp-GH3.16 was specifically upregulated by auxins and was not affected by cytokinin, gibberellin, abscisic acid or ethylene, or by heat shock, water stress or anoxia. • Pp-GH3.16 mRNAs were quantified in pine roots inoculated with two ectomycorrhizal fungi, Hebeloma cylindrosporum and Rhizopogon roseolus . Surprisingly, Pp-GH3.16 was downregulated following inoculation with both fungal species. The downregulation was most rapid on establishment of symbiosis with an indole-3- acetic acid (IAA)-overproducing mutant of H. cylindrosporum , which overproduced mycorrhizas characterized by a hypertrophic Hartig net. This indicates that, despite being auxin-inducible, Pp-GH3.16 can be downregulated on establishment of symbiosis with a fungus that releases auxin. • By contrast, Pp-GH3.16 was not downregulated in pine root systems inoculated with a nonmycorrhizal mutant of H. cylindrosporum , suggesting that the downregulation we observed in mycorrhizal root systems was a component of the molecular cross-talk between symbiotic partners at the origin of differentiation of symbiotic structures

Les PCB dans les sols : comment les éliminer?

National audienc