RNA Editing Responses to Oxidative Stress between a Wild Abortive Type Male-Sterile Line and Its Maintainer Line

Abstract

RNA editing of mitochondrial gene transcripts plays a central role during plant development and evolutionary adaptation. RNA editing has previously been reported to differ between the rice cytoplasmic male sterile (CMS) line and its maintainer line, which has been suggested as a cause for their different performances under environmental stress. To specifically test this hypothesis, a wild abortive (WA) CMS line (Huhan-1A) and its maintainer line (Huhan-1B) were utilized to investigate performances in response to oxidative stress, as well as RNA editing efficiencies on transcripts of six selected mitochondrial genes. Compared to the maintainer line, Huhan-1A represented both lower plant height and total antioxidant capacity, possessed higher total soluble protein and chlorophyll contents, accumulated less H2O2 content on the 3rd day after treatment (DAT), and exhibited higher survival ratio after re-watering. Furthermore, a total of 90 editing sites were detected on transcripts of six mitochondrial genes (atp9, nad2, nad7, nad9, ccmB, and ccmC) in both Huhan-1A and Huhan-1B on the 0, 1st, and 3rd DAT. Forty-eight sites were furthermore determined as stress-responsive sites (SRS). Generally, in response to oxidative stress, SRS in Huhan-1A increased the resulting editing efficiencies, while SRS in Huhan-1B decreased the resulting editing efficiencies. In addition, 33 and 22 sites at ccmB and ccmC were differentially edited between Huhan-1A and Huhan-1B, respectively, on the 0, 1st, and 3rd DAT. Editing efficiencies of ccmB and ccmC were generally lower in Huhan-1A (ccmB, 37.3–47.8%; ccmC, 41.2–52.3%) than those in Huhan-1B (ccmB, 82.6–86.5%; ccmC, 81.0–82.9%). Deficiencies of RNA editing in Huhan-1A at ccmB and ccmC could lead to the loss of transmembrane domains in their protein structures. Consequently, differences in RNA editing at ccmB and ccmC between the WA-CMS line and its maintainer line partially explained their different performances under stress. Moreover, we detected differences in expressions of pentatricopeptide repeat (PPR) genes between both lines, as well as significant correlations with RNA editing. Our study indicated potential associations of RNA editing and PPR genes in rice tolerance to abiotic stresses. However, the underlying molecular mechanisms of stress-adaptation, which are attributed to RNA editing on transcripts of mitochondrial genes, require further investigation.

Genome-Wide Analysis of Multiple Organellar RNA Editing Factor Family in Poplar Reveals Evolution and Roles in Drought Stress

“…In order to further explore the possible relationship between RNA editing and plant stress, we selected a total of six genes from chloroplasts and mitochondria to evaluate their expression, based on previous studies [27,38,39]. The RPS14 gene represented important chloroplast proteins, and the fluctuant editing efficiency and gene expression of RPS14 were associated with cytokinins against stress [39,40].…”

“…Under salt stress, PSBF and NDHB likely showed an elevated editing percentage, linked to PSII repair and increase in NDHB gene translation [39]. In rice, atp6 , atp9 , and ccmC were related to mitochondrial electron transport chain and had been selected to test RNA editing during stress exposure [38]. In our study, these reported genes in poplar were obtained from National Center for Biotechnology information and showed different expression owing to drought.…”

white panicle2 encoding thioredoxin z, regulates plastid RNA editing by interacting with multiple organellar RNA editing factors in rice

“…All rights reserved Chan, 2015;Choudhury et al, 2017;Farooq et al, 2019), which might in turn affect the redox status of TRXs and MORFs, and assembly of the editosome, eventually leading to changes in RNA editing efficiencies for an adaptive response. In support of this notion, a previous study in rice showed that mitochondria RNA editing was affected by oxidative stress (Xiong et al, 2017).…”

Knocking Out the Gene RLS1 Induces Hypersensitivity to Oxidative Stress and Premature Leaf Senescence in Rice

“…The culture solution, formulated as described by Chen et al [ 41 ], was replaced every two days. Following the procedure given by Xiong et al [ 42 ], ten-day old seedlings of uniform size were transferred into the same solution supplemented with 60 mM H 2 O 2 for two days, at which point the extent of necrotic and chlorotic damage was determined. The experiment consisted of three replicates, each involving 16 seedlings per line.…”