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.)

Li Hua Cui; Hye Jo Min; Mi Young Byun; Hyeong Geun Oh; Woo Taek Kim

doi:10.3389/fpls.2018.01797

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.)

Front Plant Sci. 2018 Dec 5:9:1797. doi: 10.3389/fpls.2018.01797. eCollection 2018.

Authors

Li Hua Cui^{1

2}, Hye Jo Min^{1

2}, Mi Young Byun³, Hyeong Geun Oh^{1

2}, Woo Taek Kim^{1

2}

Affiliations

¹ Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea.
² Institute of Life Science and Biotechnology, Yonsei University, Seoul, South Korea.
³ Unit of Polar Genomics, Korea Polar Research Institute, Incheon, South Korea.

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.

Keywords: RING E3 Ub ligase; abscisic acid; cold stress; drought stress; opposite response; rice (Oryza sativa).