title: Comparative proteomic analysis of soybean nodulation using a supernodulation mutant, SS2-2.
abstract: Legumes have the ability to form root nodules that fix atmospheric nitrogen through a symbiotic interaction with nitrogen-fixing bacteria. As a first step in dissecting the molecular process of nodulation, proteome reference maps of soybean roots and nodules were constructed. Time course analysis revealed that the transition from root to nodule was accompanied with downregulation of defense-response related proteins, including Mn-superoxide dismutase, peroxidase (Prx), PR10, and stress-induced protein, leading to the initiation of a symbiotic interaction between the two partners. Following nitrogenase biosynthesis, the host plant cooperated with the rhizobia to fix atmospheric nitrogen under microaerobic conditions via expression of leghemoglobins and antioxidant proteins. Comparative proteome analysis indicated lower expression of malate dehydrogenase (MDH), leghemoglobins and nitrogenase in the nodule development of the supernodulation mutant, SS2-2, as compared to the wild type, indicating that SS2-2 forms functionally immature nodules in higher numbers with the lower activity of nitrogen fixation.
authors.affiliation: Department of Crop Science and Biotechnology, Dankook University, Cheonan, Chungnam, Republic of Korea.
authors.forename: Chae Woo
authors.initials: CW
authors.lastname: Lim
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Park
authors.forename: Suk Ha
authors.initials: SH
authors.lastname: Lee
authors.forename: Cheol Ho
authors.initials: CH
authors.lastname: Hwang
mesh_terms: D009154:Mutation; D055170:Plant Root Nodulation; D040901:Proteomics / Q000379:methods*; D053204:Root Nodules, Plant / Q000378:metabolism; D013025:Glycine max / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology