OsGLO4 is involved in the formation of iron plaques on surface of rice roots grown under alternative wetting and drying condition
2018
Yu, Xiao-Li | Wu, Dao-Ming | Fu, You-Qiang | Yang, Xu-Jian | Baluška, F. | Shen, Hong
BACKGROUND AND AIM: The molecular physiological mechanism of alternative wetting and drying (AWD) promoting iron plaque (IP) formation is unknown. Here, we report that a glycolate oxidase (GLO) gene, OsGLO4 contributes to AWD-induced IP formation. METHODS: Rice plants were grown in sand to explore the relationship among IP content, GLO activity, H₂O₂ concentration and OsGLO4 expression under AWD treatment. RESULTS: AWD significantly promoted GLO activity, OsGLO4 expression,and IP content in rice roots. Overexpressing OsGLO4 (OX) showed more 46.2% IP content than wild type (WT). Results with X-ray diffraction analysis indicated that OX also had a higher proportion of Feᴵᴵᴵ compound in IP in comparison to WT. The activity of GLO and H₂O₂ concentration in OX roots were 170.3% and 126.7% higher than those of WT. Interestingly, H₂O₂ distribution in epidermal cells was consistent with the spatial distribution of IP. Treatment with glycolic acid raised GLO activity by 88.9% and IP content by 33.3%; while α-hydroxy-2-pyridinemethanesulfonic acid inhibited GLO activity and reduced IP content. Exogenous H₂O₂ or treatment with aminotriazole increased the quantities of IP significantly, while dimethylthiourea reduced it. CONCLUSION: OsGLO4 is involved in the formation of IP by mediating GLO activity and H₂O₂ production under AWD condition.
显示更多 [+] 显示较少 [-]