A rice really interesting new gene H2‐type E3 ligase, OsSIRH2‐14, enhances salinity tolerance via ubiquitin/26S proteasome‐mediated degradation of salt‐related proteins

Abstract

Salinity is a deleterious abiotic stress factor that affects growth, productivity, and physiology of crop plants. Strategies for improving salinity tolerance in plants are critical for crop breeding programmes. Here, we characterized the rice (Oryza sativa) really interesting new gene (RING) H2‐type E3 ligase, OsSIRH2‐14 (previously named OsRFPH2‐14), which plays a positive role in salinity tolerance by regulating salt‐related proteins including an HKT‐type Na+ transporter (OsHKT2;1). OsSIRH2‐14 expression was induced in root and shoot tissues treated with NaCl. The OsSIRH2‐14‐EYFP fusion protein was predominately expressed in the cytoplasm, Golgi, and plasma membrane of rice protoplasts. In vitro pull‐down assays and bimolecular fluorescence complementation assays revealed that OsSIRH2‐14 interacts with salt‐related proteins, including OsHKT2;1. OsSIRH2‐14 E3 ligase regulates OsHKT2;1 via the 26S proteasome system under high NaCl concentrations but not under normal conditions. Compared with wild type plants, OsSIRH2‐14‐overexpressing rice plants showed significantly enhanced salinity tolerance and reduced Na+ accumulation in the aerial shoot and root tissues. These results suggest that the OsSIRH2‐14 RING E3 ligase positively regulates the salinity stress response by modulating the stability of salt‐related proteins.

Oryza sativa,C4HC3‐type really interesting new gene (RING),OsRFPv6, is a positive regulator in response to salt stress by regulating Na+absorption

“…This is a modified figure from a previous study (Assaha et al, 2017). Regulation of OsHKT2;1 via OsSIRPH2-14 has been reported (Park et al, 2019). XPCs: xylem parenchyma cells which is a K + inward rectifier (Fuchs et al, 2005), exhibited low expression levels in the roots and leaves of transgenic plants.…”

Comprehensive dissection into morpho-physiologic responses, ionomic homeostasis, and transcriptomic profiling reveals the systematic resistance of allotetraploid rapeseed to salinity

“…1 a, b), which was not suitable for the crop SSR study. Finally, the NaCl concentration suitable for studying salinity of rapeseed was determined to be 200 mM, which was also widely used in other studies [ 35 – 39 ]. It might be concluded that 200 mM NaCl could be used as a universal condition for the crop SSR study under hydroponic culture.…”

Research Progress on Plant RING-Finger Proteins

“…OsSIRP1 is a negative regulator of salt tolerance, and its target protein needs to be further studied [49,60]. The microtubule-associated RING finger protein 1 (OsMAR1), an E3 ligase, acts as a negative regulator for salt-stress response through the regulation of the O. sativa chymotrypsin protease inhibitor 2 (OsCPI2), but anther rice RING H2-type E3 ligase, OsSIRH2-14 (previously named OsRFPH2-14), plays a positive role in salinity tolerance by regulating salt-related proteins, including an HKT-type Na+ transporter (OsHKT2; 1) [55,59]. The RING-finger proteins M. esculenta RZF (MeRZF) and SpRing were found to respond to salt stress in cassava and wild tomato, respectively.…”