2008/03/03 by Hassen Gherbi, Katharina Markmann, Sergio Svistoonoff +9 · 292 citations
Agricultural and Biological Sciences · #Legume Nitrogen Fixing Symbiosis #Plant nutrient uptake and metabolism #Nematode management and characterization studies #Biology #Frankia #Rhizobia #Symbiosis #Arbuscular mycorrhiza #Actinorhizal plant #Botany #Glomeromycota #Lotus japonicus #Root nodule #Mycorrhiza #Medicago truncatula #Nitrogen fixation #Bacteria #Genetics
paper · open access · doi:10.1073/pnas.0710618105
published in Proceedings of the National Academy of Sciences 105(12), 4928-4932 (National Academy of Sciences)
openalex publication_date 2008/03/03 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
Root endosymbioses vitally contribute to plant nutrition and fitness worldwide. Nitrogen-fixing root nodulation, confined to four plant orders, encompasses two distinct types of associations, the interaction of legumes (Fabales) with rhizobia bacteria and actinorhizal symbioses, where the bacterial symbionts are actinomycetes of the genus Frankia. Although several genetic components of the host-symbiont interaction have been identified in legumes, the genetic basis of actinorhiza formation is unknown. Here, we show that the receptor-like kinase gene SymRK, which is required for nodulation in legumes, is also necessary for actinorhiza formation in the tree Casuarina glauca. This indicates that both types of nodulation symbiosis share genetic components. Like several other legume genes involved in the interaction with rhizobia, SymRK is also required for the interaction with arbuscular mycorrhiza (AM) fungi. We show that SymRK is involved in AM formation in C. glauca as well and can restore both nodulation and AM symbioses in a Lotus japonicus symrk mutant. Taken together, our results demonstrate that SymRK functions as a vital component of the genetic basis for both plant-fungal and plant-bacterial endosymbioses and is conserved between legumes and actinorhiza-forming Fagales.