tailieunhanh - báo cáo khoa học: "Arbuscular mycorrhizal symbiosis elicits shoot proteome changes that are modified during cadmium stress alleviation in Medicago truncatula"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Arbuscular mycorrhizal symbiosis elicits shoot proteome changes that are modified during cadmium stress alleviation in Medicago truncatula | Aloui et al. BMC Plant Biology 2011 11 75 http 1471-2229 11 75 BMC Plant Biology RESEARCH ARTICLE Open Access Arbuscular mycorrhizal symbiosis elicits shoot proteome changes that are modified during cadmium stress alleviation in Medicago truncatula 1 t 1 1 3 4 Achref Aloui Ghislaine Recorbet Franck Robert Benoit Schoefs Martine Bertrand Céline Henry Vivienne Gianinazzi-Pearson1 Eliane Dumas-Gaudot1 and Samira Aschi-Smiti2 Abstract Background Arbuscular mycorrhizal AM fungi which engage a mutualistic symbiosis with the roots of most plant species have received much attention for their ability to alleviate heavy metal stress in plants including cadmium Cd . While the molecular bases of Cd tolerance displayed by mycorrhizal plants have been extensively analysed in roots very little is known regarding the mechanisms by which legume aboveground organs can escape metal toxicity upon AM symbiosis. As a model system to address this question we used Glomus irregulare-colonised Medicago truncatula plants which were previously shown to accumulate and tolerate heavy metal in their shoots when grown in a substrate spiked with 2 mg Cd kg-1. Results The measurement of three indicators for metal phytoextraction showed that shoots of mycorrhizal M. truncatula plants have a capacity for extracting Cd that is not related to an increase in root-to-shoot translocation rate but to a high level of allocation plasticity. When analysing the photosynthetic performance in metal-treated mycorrhizal plants relative to those only Cd-supplied it turned out that the presence of G. irregulare partially alleviated the negative effects of Cd on photosynthesis. To test the mechanisms by which shoots of Cd-treated mycorrhizal plants avoid metal toxicity we performed a 2-DE MALDI TOF-based comparative proteomic analysis of the M. truncatula shoot responses upon mycorrhization and Cd exposure. Whereas the metal-responsive shoot proteins currently identified in non-mycorrhizal