The Rice GLYCINE-RICH PROTEIN 3 Confers Drought Tolerance by Regulating mRNA Stability of ROS Scavenging-Related Genes

Jae Sung Shim; Su-Hyun Park; Dong-Keun Lee; Youn Shic Kim; Soo-Chul Park; Mark Christian Felipe R Redillas; Jun Sung Seo; Ju-Kon Kim

doi:10.1186/s12284-021-00473-0

The Rice GLYCINE-RICH PROTEIN 3 Confers Drought Tolerance by Regulating mRNA Stability of ROS Scavenging-Related Genes

Rice (N Y). 2021 Mar 19;14(1):31. doi: 10.1186/s12284-021-00473-0.

Authors

Jae Sung Shim^#^{1

2}, Su-Hyun Park^#^{1

3}, Dong-Keun Lee^{1

4}, Youn Shic Kim^{1

5}, Soo-Chul Park^{1

6}, Mark Christian Felipe R Redillas⁷, Jun Sung Seo⁸, Ju-Kon Kim⁹

Affiliations

¹ Crop Biotechnology Institute, GreenBio Science and Technology, Seoul National University, Pyeongchang, 25354, South Korea.
² School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186, South Korea.
³ Temasek Life Sciences Laboratory, 1 Research Link, National University of Singapore, Singapore, 117604, Singapore.
⁴ E GREEN GLOBAL, Gunpo, 15843, South Korea.
⁵ Agriculture and Life Sciences Research Institute, Kangwon National University, Chuncheon, 24341, South Korea.
⁶ Department of Agricultural Biotechnology, National Academy of Agricultural Science, Rural Development Administration, Jeonju, 54874, South Korea.
⁷ Biology Department, De La Salle University, 0922, Manila, Philippines.
⁸ Crop Biotechnology Institute, GreenBio Science and Technology, Seoul National University, Pyeongchang, 25354, South Korea. xfiles96@snu.ac.kr.
⁹ Crop Biotechnology Institute, GreenBio Science and Technology, Seoul National University, Pyeongchang, 25354, South Korea. jukon@snu.ac.kr.

^# Contributed equally.

Abstract

Background: Plant glycine-rich proteins are categorized into several classes based on their protein structures. The glycine-rich RNA binding proteins (GRPs) are members of class IV subfamily possessing N-terminus RNA-recognition motifs (RRMs) and proposed to be involved in post-transcriptional regulation of its target transcripts. GRPs are involved in developmental process and cellular stress responses, but the molecular mechanisms underlying these regulations are still elusive.

Results: Here, we report the functional characterization of rice GLYCINE-RICH PROTEIN 3 (OsGRP3) and its physiological roles in drought stress response. Both drought stress and ABA induce the expression of OsGRP3. Transgenic plants overexpressing OsGRP3 (OsGRP3^OE) exhibited tolerance while knock-down plants (OsGRP3^KD) were susceptible to drought compared to the non-transgenic control. In vivo, subcellular localization analysis revealed that OsGRP3-GFP was transported from cytoplasm/nucleus into cytoplasmic foci following exposure to ABA and mannitol treatments. Comparative transcriptomic analysis between OsGRP3^OE and OsGRP3^KD plants suggests that OsGRP3 is involved in the regulation of the ROS related genes. RNA-immunoprecipitation analysis revealed the associations of OsGRP3 with PATHOGENESIS RELATED GENE 5 (PR5), METALLOTHIONEIN 1d (MT1d), 4,5-DOPA-DIOXYGENASE (DOPA), and LIPOXYGENASE (LOX) transcripts. The half-life analysis showed that PR5 transcripts decayed slower in OsGRP3^OE but faster in OsGRP3^KD, while MT1d and LOX transcripts decayed faster in OsGRP3^OE but slower in OsGRP3^KD plants. H₂O₂ accumulation was reduced in OsGRP3^OE and increased in OsGRP3^KD plants compared to non-transgenic plants (NT) under drought stress.

Conclusion: OsGRP3 plays a positive regulator in rice drought tolerance and modulates the transcript level and mRNA stability of stress-responsive genes, including ROS-related genes. Moreover, OsGRP3 contributes to the reduction of ROS accumulation during drought stress. Our results suggested that OsGRP3 alleviates ROS accumulation by regulating ROS-related genes' mRNA stability under drought stress, which confers drought tolerance.

Keywords: Cytoplasmic foci; Drought tolerance; OsGRP3; RNA-IP; mRNA stability.

Grants and funding

PJ01477201/Rural Development Administration, Republic of Korea