miR398 regulation in rice of the responses to abiotic and biotic stresses depends on CSD1 and CSD2 expression

Abstract

MiR398 targets two Cu or Zn superoxide dismutases (CSD1 and CSD2) in Arabidopsis thaliana (L.) Heynh. Here we provide evidence that rice (Oryza sativa L.) miR398 mediates responses to abiotic and biotic stresses through regulating the expression of its target genes, Os-CSD1 and Os-CSD2. Rice plants were exposed to various stresses, including high Cu2+, high salinity, high light, methyl viologen, water stress, pathogens and ethylene, and the molecular response was investigated. Rice plants overexpressing Os-miR398 and the miR398-resistant form of Os-CSD2 were also exposed to these stresses. Both abiotic and biotic stresses significantly inhibited Os-miR398 expression and thus stimulated the expression of Os-CSD1 and Os-CSD2. The plant hormone ethylene produced an especially marked response. Transgenic rice lines that overexpressed Os-miR398 had a lower expression of CSD1 and -2 and were more sensitive to environmental stress. Conversely, transgenic rice lines which overexpressed the miR398-resistant form of Os-CSD2 showed more tolerance to high salinity and water stress than non-transgenic rice. We conclude that Os-miR398 regulates the responses of rice to a wide range of environmental stresses and to ethylene, and exerts its role through mediating CSDs expression and cellular ROS levels.

The Populus Superoxide Dismutase Gene Family and Its Responses to Drought Stress in Transgenic Poplar Overexpressing a Pine Cytosolic Glutamine Synthetase (GS1a)

“…Although miRNAs were not investigated in the present study, stimulation of poplar miR398s by drought may be expected based on the strong down-regulation of their predicted targets, PtCSD1s , PtCSD2s and PtCCSs [62], [63], as has been reported for Medicago [64]. Another important yet relatively less emphasized role of miR398 is its involvement in the regulation of Cu homeostasis [65].…”

A putative AGO protein, OsAGO17, positively regulates grain size and grain weight through OsmiR397b in rice

“…The expression levels of some miRNAs were changed in the OsAGO17 transgenic plants, such as OsmiR156j, OsmiR396c, OsmiR398b and OsmiR408, all of which have been reported to regulate seed development in rice (Jiao et al, 2010;Zhang et al, 2017a,b), so there may be a complex regulatory network associated with OsAGO17. In addition, OsmiR397, OsmiR398 and OsmiR408 also play an important role in abiotic and biotic stress responses (Jia et al, 2009;Lu et al, 2011;Pan et al, 2017). OsLAC8 and OsLAC29 were significantly induced by salt stress in both salt-sensitive cultivars (Liu et al, 2017).…”

The advance of tomato disease-related microRNAs

“…In a recent research, it was observed that the expression level of miR398 decreased gradually in tomato leaves, after Phytophthora infestans (P. infestans) infection . Under pathogen attack, miR398 were down-regulated in several other plant species, while CSD1 and CSD2 were up-regulated, further detoxifying ROS (Jagadeeswaran et al 2009;Lu et al 2011;Naya et al 2014). Indeed, functional analyses have demonstrated that Nicotiana benthamiana (N. benthamiana) leaves transiently overexpressing miR398b were more susceptible to Sclerotinia sclerotiorum infection (Naya et al 2014).…”