RT-PCR |
Nodule formation |
up-regulated |
N/A |
The over expression of enod40 in M.truncatula plants infected by Sinorhizobium melilotiresulted in fast nodulation of these transgenic plants. Altered levels of enod40 expression considerably affect nodule induction by S.meliloti. During this symbiotic interaction, overexpression of enod40 resulted in accelerated nodulation and enhanced root growth of transgenic plants. Those plants in which silencing of enod40 gene expression was detected exhibited reduced nodulation capacity. (Charon et al., 1999) Mycorrhizal colonization is regulated by enod40, an early nodulin gene known to be involved in the nodule symbiosis of legumes with nitrogen-fixing bacteria. Medicago truncatula plants overexpressing enod40 exhibited stimulated mycorrhizal colonization in comparison with control plants. Overexpression of enod40 promoted fungal growth in the root cortex and increased the frequency of arbuscule formation. enod40 might be a plant regulatory gene involved in the control of the mycorrhizal symbiosis. Overexpression of enod40 Promotes Development of Arbuscules. M.truncatula plants overexpressing enod40 exhibited accelerated mycorrhizal colonization.This paper shows that alteration in the transcript level of the enod40 gene has an effect on the growth of mycorrhizal fungi in the root and on the development of cells containing arbuscules. (Staehelin et al., 2001) ENOD40 expression was detected in cells surrounding the giant cells but not within the giant cells. ENOD40 up-regulation in giant cells and their surrounding cells. overexpressing ENOD40, increased initiation of nodule primordia was observed at early timepoints, which was accompanied by a proliferation response close to the root tip . ENOD40 induction is a limiting step in primordium formation, ENOD40 could play a role in transport of compounds. The early nodulin gene ENOD40 involved in primordium formation and the cell cycle gene CCS52a required for cell differentiation and endoreduplication, are expressed in galls of the host plant. (Favery et al., 2002) Overexpression of enod40 in Medicago truncatula results in a considerable increase of cortical cell divisions when plants are subjected to nitrogen-limiting conditions. Interestingly, such plants infected by Sinorhizobium meliloti nodulate faster and exhibit increased sensitivity to the Nod signals upon treatment with purified Nod factors or inoculation with S.meliloti mutants. In mature nodules, enod40 is expressed in the pericycle of the vascular bundles but also in several non-symbiotic tissues. (Girard et al., 2003) ENOD40 transcripts are required for correct subcellular localization of RNP particles in legume plants.Transgenic Medicago truncatula overexpressing enod40 exhibited accelerated nodulation, whereas plants with reduced amounts of enod40 transcripts formed only a few and modified nodule-like tructures.Mtenod40 was expressed in nodules at a high level, to a lesser extent in stems and roots,and was not detected in leaves. (Campalans et al., 2004) Under nitrogenlimiting conditions overexpression of Medicago truncatula (a model leguminous plant) enod40 (Mtenod40) induces cortical cell division in Medicago roots. These experiments also showed that transient expression of either region 1 carrying box I or a 3'sequence (region 2) spanning box II evoked a response similar to that evoked by the complete gene in alfalfa (Medicago sativa) roots. (Sousa et al., 2011) Transgenic Medicago truncatula plants overexpressing or silenced for ENOD40 exhibited accelerated nodulation or form only a few and modified nodule-like structures, respectively, suggesting that MtENOD40 regulates nodule development. The ENOD40 npcRNA was shown to re-localize a nuclear-speckle RBP from the nucleus to the cytoplasm in Medicago truncatula. Plant RBPs have been also implicated in RNA-mediated chromatin silencing in the FLC locus through interaction with specific antisense transcripts. (Charon et al., 2010) |
10521525, 11752473, 12437298, 12930950, 15037734, 11113209, 11113209 |
PLNlncRbase
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