Open AccessGlutathione and Homoglutathione Play a Critical Role in the Nodulation Process of Medicago truncatula
Author(s) -
Pierre Frendo,
Judith Harrison,
Christel Norman,
Marı́a Jesús Hernández Jiménez,
Ghislaine Van de Sype,
Alain Gilabert,
Alain Puppo
Publication year - 2005
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.565
H-Index - 153
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi-18-0254
Subject(s) - medicago truncatula , glutathione , root nodule , rhizobium , biology , rhizobiaceae , nod factor , buthionine sulfoximine , biochemistry , glutathione synthetase , bacteria , microbiology and biotechnology , symbiosis , botany , enzyme , gene , genetics
Legumes form a symbiotic interaction with bacteria of the Rhizobiaceae family toproduce nitrogen-fixing root nodules under nitrogen-limiting conditions. This process involves the recognition of the bacterial Nod factors by the plant which mediates the entry of the bacteria into the root and nodule organogenesis. We have examined the importance of the low molecular weight thiols, glutathione (GSH) and homoglutathione (hGSH), during the nodulation process in the model legume Medicago truncatula. Using both buthionine sulfoximine, a specific inhibitor of GSH and hGSH synthesis, and transgenic roots expressing GSH synthetase and hGSH synthetase in an antisense orientation, we showed that deficiency in GSH and hGSH synthesis inhibited the formation of the root nodules. This inhibition was not correlated to a modification in the number of infection events or to a change in the expression of the Rhizobium sp.-induced peroxidase rip1, indicating that the low level of GSH or hGSH did not alter the first steps of the infection process. In contrast, a strong diminution in the number of nascent nodules and in the expression of the early nodulin genes, Mtenod12 and Mtenod40, were observed in GSHand hGSH-depleted plants. In conclusion, GSH and hGSH appear to be essential for proper development of the root nodules during the symbiotic interaction.