Record ID No. |
1203 |
Author(s) |
Tikhonovich,-I-A., Borisov,.A.Yu., Tsyganov,V.E. , Ovtsyna,A.O., Dolgikh,E.A., Provorov,N.A , 2005 |
Affiliation |
All-Russian Research Institute for Agricultural Microbiology, Russian Academy of Agricultural Sciences, St. Petersburg, Russia. |
Title |
Integration of plant and microbial genetic systems in symbiosis |
Source. Vol.(no):Page |
Uspekhi-Sovremennoi-Biologii. 125(3): 227-238p. |
Categories |
Arbuscular Mycorrhiza |
Subjects |
Genetics |
Host |
Plants |
Organism |
Rhizobium |
Country |
Russia, Asia |
Abstracts |
The integration of partners' genetic systems in symbioses was analysed using models of the interaction of legumes with rhizobium and fungi of arbuscular mycorrhiza. The plant genes were classified into two groups: regulators (Sym genes) and structural genes (nodulins and mycorrhizins). The Sym genes form a regulatory network, which controls: (1) organogenesis of nodules; (2) building of their symbiotic compartments; and (3) development of arbuscular mycorrhiza. Nodulins and mycorrhizins were responsible for the development of novel structures and metabolic functions in symbioses. Both groups of genes were activated by either external microbial signals or internal plant signals, both local and systemic ones (including phytohormones). A dialogue of microbes with plant defence systems was an important term of symbioses, since the impairment of this dialogue may result in the transformation of the mutualistic interaction into a pathogenic process. The partners' integration was based on the coupling of photosynthesis with nitrogen fixation (in nodules) or with phosphorus nutrition (in arbuscular mycorrhiza) that leads to the integration of plant and microbial metabolic pathways. The formation of superorganism genetic systems was a key distinction between symbioses and biocenoses. In the latter, the cycles of nutrients and energy do not require the genetic integration of organisms. |