Mulberry RGS Negatively Regulates Salt Stress Response and Tolerance

Regulator of G-protein signaling (RGS) protein, the best-characterized accelerating GTPase protein in plants, regulates G-protein signaling and plays important role in abiotic stress tolerance. However, the detailed molecular mechanism of RGS involved in G-protein signaling mediated abiotic stress responses remains unclear. In this study, a mulberry ( L.) gene () was transformed into tobacco, and the ectopic expression of in tobacco decreased the tolerance to salt stress. The transgenic tobacco plants had lower proline content, higher malonaldehyde and HO contents than wild type plants under salt stress condition. Meanwhile, overexpression in mulberry seedlings enhances the sensitivity to salt stress and RNAi-silenced expression of improves the salt stress response and tolerance. These results suggested that MaRGS negatively regulates salt stress tolerance. Further analysis suggested that D-glucose and autophagy may involve in the response of RGS to salt stress. This study revealed the role of in salt stress tolerance and provides a proposed model for RGS regulates G-protein signaling in response to salt stress.