Proteomic analysis of the flooding tolerance mechanism in mutant soybean

• Published in: Journal of proteomics 2013-02, Vol.79, p.231-250
• Main Authors: Komatsu, Setsuko, Nanjo, Yohei, Nishimura, Minoru
• Format: Article
• Language: English
• Subjects: alcohol dehydrogenase; cell walls; cultivars; fermentation; Flooding tolerance; gamma radiation; Mutant; mutants; protein synthesis; proteins; Proteomics; Root; root growth; root tips; Soybean; soybeans
• ISSN: 1874-3919
• DOI: 10.1016/j.jprot.2012.12.023

Flooding stress of soybean is a serious problem because it reduces growth; however, flooding-tolerant cultivars have not been identified. To analyze the flooding tolerance mechanism of soybean, the flooding-tolerant mutant was isolated and analyzed using a proteomic technique. Flooding-tolerance tests were repeated five times using gamma-ray irradiated soybeans, whose root growth (M6 stage) was not suppressed even under flooding stress. Two-day-old wild-type and mutant plants were subjected to flooding stress for 2days, and proteins were identified using a gel-based proteomic technique. In wild-type under flooding stress, levels of proteins related to development, protein synthesis/degradation, secondary metabolism, and the cell wall changed; however, these proteins did not markedly differ in the mutant. In contrast, an increased number of fermentation-related proteins were identified in the mutant under flooding stress. The root tips of mutant plants were not affected by flooding stress, even though the wild-type plants had damaged root. Alcohol dehydrogenase activity in the mutant increased at an early stage of flooding stress compared with that of the wild-type. Taken together, these results suggest that activation of the fermentation system in the early stages of flooding may be an important factor for the acquisition of flooding tolerance in soybean. [Display omitted] ► Cell wall loosening-related proteins are not increased in mutant under flooding stress. ► Ubiquitin/proteasome-mediated proteolysis did not occur in mutant under flooding stress. ► Activation of the fermentation system in the early stages of flooding is an important factor for flooding tolerance.