OsDIRP1, a Putative RING E3 Ligase, Plays an Opposite Role in Drought and Cold Stress Responses as a Negative and Positive Factor, Respectively, in Rice (Oryza sativa L.)

Abstract

As higher plants are sessile organisms, they are unable to move to more favorable places; thus, they have developed the ability to survive under potentially detrimental conditions. Ubiquitination is a crucial post-translational protein modification and participates in abiotic stress responses in higher plants. In this study, we identified and characterized OsDIRP1 (Oryza sativa Drought-Induced RING Protein 1), a nuclear-localized putative RING E3 ubiquitin (Ub) ligase in rice (Oryza sativa L.). OsDIRP1 expression was induced by drought, high salinity, and abscisic acid (ABA) treatment, but not by low temperature (4°C) stress, suggesting that OsDIRP1 is differentially regulated by different abiotic stresses. To investigate its possible role in abiotic stress responses, OsDIRP1-overexpressing transgenic rice plants (Ubi:OsDIRP1-sGFP) were generated, and their phenotypes were analyzed. The T4 Ubi:OsDIRP1-sGFP lines showed decreased tolerance to drought and salt stress as compared to wild-type rice plants. Moreover, Ubi:OsDIRP1-sGFP progeny were less sensitive to ABA than the wild-type during both germination and post-germination growth. In contrast, Ubi:OsDIRP1-sGFP plants exhibited markedly higher tolerance to prolonged cold (4°C) treatment. These results suggest that OsDIRP1 acts as a negative regulator during drought and salt stress, whereas it functions as a positive factor during the cold stress response in rice.

Identification of plant hormones and candidate hub genes regulating flag leaf senescence in wheat response to water deficit stress at the grain‐filling stage

“…However, there have been reports indicating that the E3 ligase (DHS) causes a negative regulation of water deficit stress by decreasing cuticular wax biosynthesis (Wang, Tian, et al., ). Cui, Min, Byun, Oh, and Kim () also reported that a putative RING E3 Ligase gene, OsDIRP1 , plays a negative role in drought and salt stress, but a positive role in cold stress response. Chitinase 8, found in the lightpink 2 module, is related to studies that previously demonstrated that a class III chitinase, DIP3, induced by drought, might play critical roles in the regulation of the rice stress response (Guo et al., ).…”

“…However, there have been reports indicating that the E3 ligase (DHS) causes a negative regulation of water deficit stress by decreasing cuticular wax biosynthesis (Wang, Tian, et al, 2018). Cui, Min, Byun, Oh, and Kim (2018) also reported that a putative RING E3…”

AtPPRT1, an E3 Ubiquitin Ligase, Enhances the Thermotolerance in Arabidopsis

“…Plants 2020, 9, x FOR PEER REVIEW 8 of 10 stress responses, and they play different functions in cold and drought signaling pathways [40][41][42].…”

“…Therefore, the mechanism of AtAIRP4 involved in the reverse regulation of salt and drought stress responses needs further study [ 39 ]. In addition, RING-type E3 ubiquitin ligases AtATL78, OsDIRP1 and CaPUB1 have opposite phenotypes in cold and drought stress responses, and they play different functions in cold and drought signaling pathways [ 40 , 41 , 42 ]. We speculate that AtPPRT1′ s ubiquitinated substrate maybe two proteins that play opposite roles in heat and drought stress responses.…”

Expression Patterns and Functional Analysis of E3 Ubiquitin Ligase Genes in Rice

“…In Arabidopsis, HOS1, AtATL78 and AtATL80 negatively regulated the tolerance to cold stress (Lee et al 2001; Kim S and Kim W 2013;Suh and Kim 2015), while PUB25 and PUB26 positively regulated the tolerance to cold stress (Wang et al 2019). OsDIRP1 positively regulated the tolerance to cold stress in rice (Cui et al 2018).…”