Aging in Legume Symbiosis. A Molecular View on Nodule Senescence in Medicago truncatula

摘要: Rhizobia reside as symbiosomes in the infected cells of legume nodules to fix atmospheric nitrogen. The symbiotic relation is strictly controlled, lasts for some time, but eventually leads nodule senescence. We present a comprehensive transcriptomics study understand onset senescence Medicago truncatula. Distinct developmental stages with characteristic gene expression were delineated during which two partners degraded consecutively, marking switch tissue status from carbon sink general nutrient source. Cluster analysis discriminated an early group that harbored regulatory genes might be primary tools interfere pod filling-related or stress-induced senescence, ultimately causing prolonged nitrogen fixation. Interestingly, transcriptomes and leaf had high degree overlap, arguing recruitment similar pathways.