Multi-omics analysis provides new insights into the changes of important nutrients and fructose metabolism in loquat bud sport mutant.

Bud sport is a common and stable somatic variation in perennial fruit trees, and often leads to significant modification of fruit traits and affects the breeding value. To investigate the impact of bud sport on the main metabolites in the fruit of white-fleshed loquat, we conducted a multi-omics analysis of loquat fruits at different developmental stages of a white-fleshed bud sport mutant of Dongting loquat (TBW) and its wild type (TBY). The findings from the detection of main fruit quality indices and metabolites suggested that bud sport resulted in a reduction in the accumulation of carotenoids, fructose, titratable acid and terpenoids at the mature stage of TBW, while leading to the accumulation of flavonoids, phenolic acids, amino acids and lipids. The comparably low content of titratable acid further enhances the balanced and pleasent taste profile of TBW. Expression patterns of differentially expressed genes involved in fructose metabolism exhibited a significant increase in the expression level of S6PDH (EVM0006243, EVM0044405) prior to fruit maturation. The comparison of protein sequences and promoter region of S6PDH between TBY and TBW revealed no structural variations that would impact gene function or expression, indicating that transcription factors may be responsible for the rapid up-regulation of S6PDH before maturation. Furthermore, correlation analysis helped to construct a comprehensive regulatory network of fructose metabolism in loquat, including 23 transcription factors, six structural genes, and nine saccharides. Based on the regulatory network and existing studies, it could be inferred that transcription factors such as ERF, NAC, MYB, GRAS, and bZIP may promote fructose accumulation in loquat flesh by positively regulating S6PDH. These findings improve our understanding of the nutritional value and breeding potential of white-fleshed loquat bud sport mutant, as well as serve as a foundation for exploring the genes and transcription factors that regulate fructose metabolism in loquat.

Effect of peer support interventions in patients with type 2 diabetes: A systematic review.

OBJECTIVE: This study aims to assess the effectiveness of a peer support intervention on the quality of life (QOL), self-management, self-efficacy, glycated hemoglobin (HbA1c), and depression in patients with type 2 diabetes mellitus (T2DM). METHODS: A systematic review was conducted by searching 10 databases, namely PubMed, The Cochrane Library, Embase, Medline, CINHAL, Web of Science, Sinomed, CNKI, WanFang Data, and VIP for articles published from January 1974 to April 2023. RESULTS: A total of 12 studies were included. A narrative synthesis of the results showed that peer support significantly improved QOL, self-management, self-efficacy, and HbA1c control in patients with T2DM, but had no significant effect on depression. CONCLUSION: Peer support is an effective intervention for individuals with T2DM. Future research should focus on more rigorously designed and larger-sample studies. PRACTICE IMPLICATIONS: Peer support proves to be effective for managing patients with T2DM. Current peer support interventions can provide valuable ideas that can guide the direction of future research.

The QTL and Candidate Genes Regulating the Early Tillering Vigor Traits of Late-Season Rice in Double-Cropping Systems.

Rice effective panicle is a major trait for grain yield and is affected by both the genetic tiller numbers and the early tillering vigor (ETV) traits to survive environmental adversities. The mechanism behind tiller bud formation has been well described, while the genes and the molecular mechanism underlying rice-regulating ETV traits are unclear. In this study, the candidate genes in regulating ETV traits have been sought by quantitative trait locus (QTL) mapping and bulk-segregation analysis by resequencing method (BSA-seq) conjoint analysis using rice backcross inbred line (BIL) populations, which were cultivated as late-season rice of double-cropping rice systems. By QTL mapping, seven QTLs were detected on chromosomes 1, 3, 4, and 9, with the logarithm of the odds (LOD) values ranging from 3.52 to 7.57 and explained 3.23% to 12.98% of the observed phenotypic variance. By BSA-seq analysis, seven QTLs on chromosomes 1, 2, 4, 5, 7, and 9 were identified using single-nucleotide polymorphism (SNP) and insertions/deletions (InDel) index algorithm and Euclidean distance (ED) algorithm. The overlapping QTL resulting from QTL mapping and BSA-seq analysis was shown in a 1.39 Mb interval on chromosome 4. In the overlap interval, six genes, including the functional unknown genes Os04g0455650, Os04g0470901, Os04g0500600, and ethylene-insensitive 3 (Os04g0456900), sialyltransferase family domain containing protein (Os04g0506800), and ATOZI1 (Os04g0497300), showed the differential expression between ETV rice lines and late tillering vigor (LTV) rice lines and have a missense base mutation in the genomic DNA sequences of the parents. We speculate that the six genes are the candidate genes regulating the ETV trait in rice, which provides a research basis for revealing the molecular mechanism behind the ETV traits in rice.

Morphological and phylogenetic analyses reveal a new species of Anthracophyllum (Omphalotaceae, Agaricales) in Zhejiang Province, China.

During the investigations of macrofungi resources in Zhejiang Province, China, an interesting wood rot fungus was collected. Based on morphological and molecular phylogenetic studies, it is described as a new species, Anthracophyllum sinense. A. sinense is characterized by its sessile, charcoal black and pleurotoid pileus, sparse lamellae occasionally branching, clavate basidia with long sterigmata [(3-)6-7(-8) µm], and non-heteromorphous cystidia. A. sinense establishes a separate lineage close to A. archeri and A. lateritium in the phylogenetic tree.

Phylogenetic and Morphological Evidence Reveal Five New Species of Boletes from Southern China.

Fungi of the order Boletales are extremely important in both ecology and economy, since most of them are ectomycorrhizal fungi, which play vital roles in maintaining forest ecosystems, water and soil protection, vegetation restoration and so on. Although previous studies have shown that this order has a very high species diversity in China, there are few reports on the species diversity of boletes in Jiangxi Province, China. Based on morphological (macroscopic and microscopic morphological characteristics) and phylogenetic analyses (ITS, LSU, and TEF1-α sequences), in this study, the wild boletes in Jiangxi Province were investigated, and five new species are described: Austroboletus albus, Xanthoconium violaceipes, Xanthoconium violaceofuscum, Xerocomus rutilans and Xerocomus subsplendidus. Descriptions and hand drawings of the new species are presented.

A new species of Dictyochaeta (Sordariomycetes, Chaetosphaeriales, Chaetosphaeriaceae) from freshwater habitats in China.

Background: Freshwater fungi refer to the fungi that depend on the freshwater habitats for the whole life cycle or part of their life cycle. In this context, a new aquatic hyphomycete was isolated from decaying wood in a freshwater habitat in Jiangxi Province, China. New information: Dictyochaetajiangxiensis sp. nov., a new aquatic hyphomycete, is characterised by its unbranched, septate, base-fertile conidiophores with multisepta and single phialide at the apex, brown, sterile seta, monophialidic, subcylindrical conidiogenous cells narrowing below the funnel-shaped collarette, hyaline, unicellular, thin-walled, smooth, guttulate, falcate to subclavate conidia narrowly rounded at both ends with hair-like appendages. Phylogenetically, the new species Dictyochaetajiangxiensis clustered together with Dictyochaetabrevis MFLU 19-0216 in a well-supported clade, but formed a separate branch. In order to better define the taxonomic status of the new species, a phylogenetic tree of most closely-related taxa in Chaetosphaeriaceae was established, based on multi-locus sequences (ITS and LSU). The novel species is described and illustrated. Newly-generated molecular data of Dictyochaetajiangxiensis is also provided.

Three novel species of Distoseptispora (Distoseptisporaceae) isolated from bamboo in Jiangxi Province, China.

Decaying bamboo in freshwater is a unique eco-environment for fungi. Three new Distoseptispora (Distoseptisporaceae) species, D.meilingensis, D.yongxiuensis and D.yunjushanensis from submerged decaying bamboo culms in Jiangxi Province, China, were discovered, based on phylogenetic analyses and morphological characters. The combined data of ITS-LSU-SSU-Tef1 sequences were used to infer the phylogenetic relationship between D.meilingensis, D.yongxiuensis, D.yunjushanensis and related species. Both molecular analyses and morphological data supported D.meilingensis, D.yongxiuensis and D.yunjushanensis as three independent taxa.

Analysis of genetic diversity among Chinese Cyclocybe chaxingu strains using ISSR and SRAP markers.

Background: Cyclocybe chaxingu is an edible and medicinal fungal species commonly cultivated in China. The major problems currently facing by growers of C. chaxingu is the random labeling of strains and strains aging and degeneration. Therefore, an evaluation of genetic diversity is essential for the conservation and reproducing programs of this species. Methods: In the present study, 24 widely cultivated strains were collected from the main producing areas of China, and the genetic diversity analysis was performed. DNA polymorphism among these Chinese C. chaxingu strains was analyzed using inter-simple sequence repeat (ISSR) and sequence-related amplified polymorphism (SRAP) markers. Results: Eight ISSR primers amplified a total of 75 DNA fragments of which 61 (81.33%) were polymorphic. Fifteen SRAP primer combinations amplified 166 fragments of which 132 (79.52%) were polymorphic. Cluster analysis showed that the C. chaxnigu strains fall into five groups with a genetic distance values ranging from 0.06 to 0.60 by ISSR analysis, while the SRAP analysis divided the test strains into four groups within the range of genetic distance from 0.03 to 0.57. The results of the present study reveal a high level of genetic diversity among the widely cultivated C. chaxingu strains.

Retiboletus atrofuscus (Boletaceae, Boletales), a new species from China.

Based on morphological and phylogenetic analyses, an ectomycorrhizal fungus collected from Jiangxi, China, is described as a new species. R. atrofuscus is morphological characterized by a dark gray to black pileus, white to pale yellowish white hymenophore, a grayish brown to pale yellow context, which turning orange-yellow to rusty yellow when injured, a prominently and coarsely white to pale yellow to black reticulation on upper 3/4 or entire stipe, grayish yellow to pale yellow to yellowish brown basidiospores in KOH with measuring (7-)7.5-13(-13.5) × (3-)3.5-5(-5.5) µm. Phylogenetic analysis results showed that R. atrofuscus formed an independent lineage within Retiboletus. Descriptions and hand drawings of the new species and comparisons with similar species are presented.

Aquapteridospora jiangxiensis, a new aquatic hyphomycetous fungus from a freshwater habitat in China.

During an investigation of freshwater fungi in Jiangxi province, China, a new hyphomycetous fungus, Aquapteridospora jiangxiensis, was collected and isolated. Aquapteridospora jiangxiensis is characterized by its unbranched and guttulate conidiophores with multi-septa swollen at the base, polyblastic conidiogenous cells with sympodial proliferations, and denticles, and guttulate conidia with a sheath. A photo plate of the macro- and micro-morphology and a muti-loci (ITS, LSU, SSU, TEF1 and RPB2) phylogenetic tree are provided. A key to the species of Aquapteridospora is also presented in this paper.

Osthole inhibits the migration and invasion of highly metastatic breast cancer cells by suppressing ITGα3/ITGß5 signaling.

Metastasis is the leading cause of death in breast cancer patients. Osthole, as an active compound detected in the traditional Chinese medicine Wenshen Zhuanggu Formula, has shown a promising anti-metastatic activity in human breast cancer cells, but the underlying mechanisms remain ambiguous. In this study we elucidated the anti-metastatic mechanisms of osthole in highly metastatic breast cancer cells and a zebrafish xenograft model. We showed that the expression of integrin α3 (ITGα3) and integrin ß5 (ITGß5) was upregulated in highly metastatic MDA-MB-231, MDA-MB-231BO breast cancer cell lines but was downregulated in poorly metastatic MCF-7 breast cancer cell line, which might be the key targets of osthole's anti-metastatic action. Furthermore, we showed that knockdown of ITGα3 and ITGß5 attenuated breast cancer cell migration and invasion possibly via suppression of FAK/Src/Rac1 pathway, whereas overexpression of ITGα3 and ITGß5 caused the opposite effects. Consistently, osthole significantly inhibited breast cancer metastasis by downregulating ITGα3/ITGß5 signaling in vitro and in vivo. These results provide new evidence that osthole may be developed as a candidate therapeutic drug for metastatic breast cancer.

Phaeoisarialaianensis (Pleurotheciales, Pleurotheciaceae), a new species from freshwater habitats in China.

Background: Freshwater fungi play an indispensable role in the ecosystem and have great research value. Based on morphological and phylogenetic analyses of a concatenated dataset of ITS, LSU and SSU sequences, a new species, Phaeoisarialaianensis, was introduced as a freshwater hyphomycete from Anhui Province, China. New information: Phaeoisarialaianensis was morphologically described as erect, rigid, dark brown to black, velvety synnemata which has macronematous, septate, branched, brown to dark brown, parallel adpressed conidiophores with polyblastic, integrated, terminal, hyaline to pale brown, smooth, denticulate, sympodial conidiogenous cells and ellipsoidal to obovoid, rounded at the apex, obtuse and tapering towards base, septate, guttulate conidia. Based on molecular and morphological characteristics, it is confirmed to be a new species. All illustrations and descriptions have been provided.

Menisporopsisaquatica sp. nov. (Sordariomycetes, Chaetosphaeriales, Chaetosphaeriaceae), from freshwater habitat in China.

Background: Freshwater fungi are an integral part of freshwater ecosystems. They promote the carbon cycle of the ecosystem by decomposing wood substrates. Menisporopsis is a fungal genus of Chaetosphaeriales in Sordariomycetes, which has been commonly collected from aquatic and marine environments. Most species of this genus are saprophytes. New information: Here, a new freshwater hyphomycetous fungus, Menisporopsisaquatica, reported from submerged rotten wood samples collected in a stream in Zhejiang Province, south-eastern China. The new species is characterised by hyaline conidia appendiculate with 1-2 setulae at each end and synnematous conidiophores growing closely around a black central seta. Molecular phylogeny of Menisporopsis was studied using a combined two-loci dataset, including the internal transcribed spacer sequences (ITS) and the nuclear ribosomal large subunit gene sequences (nrLSU). The new species is illustrated and a synopsis of the Menisporopsis species is presented in this paper.

Sporidesmiellalignicola sp. nov., a new hyphomycetous fungus from freshwater habitats in China.

BACKGROUND: Freshwater fungi, growing on submerged wood, can promote the degradation of organisms and the reuse of rotten wood energy and play key roles in freshwater ecosystems. Here, a new hyphomycetous fungus, Sporidesmiellalignicola, was isolated and identified from submerged wood samples collected in a small stream in Jiangxi Province, south-eastern China. NEW INFORMATION: The new taxon was studied, based on morphological characters and phylogenetic analyses combined with LSU, ITS, TEF1α and RPB2 sequences data. Sporidesmiellalignicola was morphologically characterised by its pink colonies on PDA medium in prophase, macronematous, mononematous, solitary, brown, septate, unbranched, straight or slightly flexuous conidiophores with holoblastic, polyblastic, integrated, terminal, pale brown conidiogenous cells and cylindrical, narrowly clavate, broadly obovoid to cuneiform, 3-4-distoseptate, olivaceous brown or brown conidia with rounded apex. A phylogenetic tree was constructed, based on the combination of LSU, ITS, TEF1α and RPB2 sequences data.

Extracts of Vine Tea Improve Diet-Induced Non-Alcoholic Steatohepatitis Through AMPK-LXRα Signaling.

Chinese vine tea can improve glucose and lipid metabolic disorders. However, its protective effects in non-alcoholic steatohepatitis (NASH) and its underlying molecular mechanisms remain unclear. Liver X receptor α (LXRα) inhibition and adenosine monophosphate-(AMP)-activated protein kinase (AMPK) activation can enhance control of NASH. AMPK activators have also been shown to inactivate LXRα. Here, the anti-NASH effects of vine tea extract (VTE) dosed at 1 g.100 g-1 diet were investigated using NASH mice challenged with a methionine and choline-deficient l-amino acid diet (MCDD) and a high-fat diet (HFD). Pharmacological mechanisms of VTE were explored using TUNEL staining, AMPK inhibition, Western blot, reporter assays, qRT-PCR analyses, and immunofluorescence. VTE treatment improved fatty liver in HFD-induced mice, while it alleviated the progression of NASH including protecting against liver lipid accumulation, steatosis, endoplasmic reticulum stress, apoptosis, inflammation, and functional injury in MCDD-fed mice. VTE reduced the action of hepatic lipogenic genes, F4/80, pro-inflammatory cytokines, CHOP, and cleaved Caspase-3 expression, while promoting expression of fatty acid oxidation genes CPT1α, ß. VTE also enhanced AMPK and blocked LXRα signaling in mouse livers. In vitro results indicated that VTE increased AMPK phosphorylation and reduced LXRα activity in HepG2 cells. Conversely, the antagonistic effect of VTE on LXRα was decreased through AMPK inhibition. Our data suggests that VTE may improve diet-induced NASH, which involves the pharmacological modulation of the AMPK-LXRα signaling pathway.

[Effects of Notch3 on gene expression and signal pathway of pancreatic stellate cell activation].

Objective: The pancreatic stellate cells( PSCs) of mice were isolated and cultured and the effects of Notch3 siRNA on PSCs gene expression were detected. Methods: were PSCs of mice were isolated and cultured. The expressions of α-SMA, fibonectin and collagen I in activated PSCs were detected by immunofluorescence. The PSCs were divided into four groups, blank control group (MOCK group), negative siRNA control group (NC group) , Notch3 siRNA group (N3 siRNA group) and Notch3 siRNA-1 group (N3 siRNA-1 group). Cell treatment: the same transfection method was applied to transfect PSCs for 48h. Then total RNA was extracted from each group, and the concentration and purity of RNA was measured. The transcriptome sequencing and analysis were performed by ANOROAD Gene technology (Beijing) co., LTD. Results: The immunofluorescence results showed that α-SMA, fibonectin and collagen I were significantly expressed in activated PSCs. The analysis of the sequencing results showed that the gene expressions of α-SMA, collagen I, fibronectin, CTGF and PCNA of PSCs were down-regulated in N3 siRNA group and N3 siRNA-1 group comparing with NC group. The genes involved in collagen metabolism were up-regulated, the gene expression of positive regulation of collagen biosynthesis was down-regulated, while that of negative regulation of collagen biosynthesis was up-regulated in N3 siRNA group and N3 siRNA-1 group comparing with NC group. The genes that regulated cell aggregation were down-regulated, and the genes that regulated extracellular matrix were down regulated in N3 siRNA group and N3 siRNA-1 group comparing with NC group. Inhibition of Notch3 expression in PSCs could affect the gene expressions of cell adhesion molecule signaling pathway, MAPK signaling pathway and TGF-ß signaling pathway. Conclusion: Inhibition of Notch3 expression can inhibit activation of PSCs , and reduce the ability of proliferation, migration and aggregation and ECM synthesis of PSCs. Inhibition of Notch3 expression may affect other signal pathways such as cell adhesion molecule signaling pathway, MAPK signaling pathway and TGF-ß signaling pathway, but its effects need further validation.

Comprehensive Analysis of Differentially Expressed lncRNAs miRNAs and mRNA and Their ceRNA Network of Patients With Rare-Earth Pneumoconiosis.

Rare-earth pneumoconiosis (REP) is the main occupational disease of rare earth exposed workers and there is no specific treatment. In this study, we performed high-throughput sequencing on the plasma of nine REP to describe and analyze the expression profiles of long non-coding RNA (lncRNA), micro RNA (miRNA) and mRNA and investigate their regulatory networks. Our results identified a total of 125 lncRNAs, 5 miRNAs, and 82 mRNAs were differentially expressed in the plasma of patients with REP. Furthermore, Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to analyze the differentially expressed non-coding RNAs (ncRNA). We found the differential expression of ncRNA are mainly related to the response of cells to stimulation, Hedgehog signaling pathway and so on. We also constructed lncRNA-miRNA-mRNA networks to further explore their underlying mechanism and possible relationships in REP. We found that in the competitive endogenous RNA (ceRNA) networks, lncRNA acts as a sponge of miRNA to regulate the target gene. The expression results were verified by qRT-PCR and the protein interaction networks of differentially expressed genes were constructed via the STRING database. OncoLnc online platform was used to do the lung cancer survival analysis among the top five mRNA analyzed by Protein-protein interaction (PPI) network analysis. We found miR-16-2-3p may used as biomarker for REP, because it is closely related to the occurrence and prognosis of REP through inflammatory reaction and in lung squamous cell carcinoma, its expression levels were positively correlated with the overall survival rate of patients.

Sensitivity analysis of heat and mass transfer characteristics during forced-air cooling process of peaches on different air-inflow velocities.

Peach is one of the most perishable fruits. During forced-convection cooling, the heat sources (respiratory and evaporative latent heat) internal to freshly harvested peaches have a remarkable influence on its evaluation of cooling characteristics with respect to various cooling strategies. Therefore, to improve the accuracy of simulation results in peaches cooling, the term of heat source was coded as detailed procedures and included into a computational fluid dynamics (CFD) model. By comparing the temperature simulated with and without considering these heat sources, it is found that a reasonable decrease in variations of cooling performances is obtained with sustained increase in air-inflow velocities. A maximum discrepancy in peaches volume-weighted average temperature (∆T vwa-max) is mainly concentrated in 0.1-0.3°C when the air-inflow velocity not exceeds 1.7 m/s, and its corresponded 7/8ths cooling time (SECT) is also prolonged by 1-6 min. This means that, below 1.7 m/s, these heat sources should be added as a term into the heat transfer equations for modifying the mathematical model inside peaches computational domain. Furthermore, the feasibility of this modeling method is confirmed by a great agreement with experiments, and its modified model has a higher accuracy with the decreased RMSE and MAPE values of 6.90%-11.26% and 7.28%-12.95%, respectively.

[Effects of obatoclax combined with gemcitabine on breast cancer cells under hypoxia condition].

Objective: To explore the effects of obatoclax(OBX) combined with gemcitabine(GEM) on breast cancer cells MCF-7 and BT-20 cell activity, migration, invasion and apoptosis under hypoxia condition.Methods: Breast cancer cells MCF-7 and BT-20 were divided into normal group, hypoxia group, GEM group, OBX+GEM group. Normal group: Cells were cultured at 37℃, 5% CO2 for 24 h and 48 h; Hypoxia group: Cells were cultured at 37℃, 1% O2, 5% CO2, 94% N2 for 24 h and 48 h; GEM group: Cells were cultured at 37℃, 1% O2, 5% CO2, 94% N2, adding 10 µmol/L GEM for 24 h and 48 h; OBX + GEM group: Cells were cultured at 37℃, 1% O2, 5% CO2, 94% N2, adding 10 µmol/L GEM and 50 nmol/L OBX for 24 h and 48 h. Western blot method was used to detect the expressions of HIF-1α in MCF-7 and BT-20 cells under normal oxygen and hypoxia condition. CCK-8 method was used to detect cancer cell activity, each group was provided with 15 compound holes. Scratch experiment was used to detect cells migration ability, each group was provided with 6 compound holes. Western blot method was used to detect the expressions of vimentin, E-Cadherin and p53 protein in cells of each group. Results: Under hypoxia condition, the expression of HIF-1α in MCF-7 and BT-20 cells was much higher than that under normal oxygen(P＜0.05). Compared with hypoxia group, GEM could reduce MCF-7 and BT-20 cells migration ability(P＜0.01)and cell activity(P＜0.05), while decrease the expression of vimentin protein(P＜0.01)and promote the expressions of E-Cadherin (P＜0.01)and p53 protein(P＜0.01) in tumor cells under hypoxia condition. In OBX combined with GEM group, the cell activity and the migration ability of MCF-7 and BT-20 were reduced significantly(P＜0.01). The expression of vimentin in cells was further reduced(P＜0.01). The expressions of E-Cadherin(P＜0.01)and p53(P＜0.01) protein were increased significantly compared with GEM group. Conclusion: Under hypoxia condition, OBX combined with a low-dose of GEM can significantly inhibit the growth, migration and invasion of breast cancer cells, and enhance the pro-apoptotic effect of GEM, but the specific mechanism needs further study.

Cytosine methylations in the promoter regions of genes involved in the cellular oxidation equilibrium pathways affect rice heat tolerance.

BACKGROUND: High temperatures, particularly at night, decrease rice yield and quality. As high nighttime temperatures (HNTs) become increasingly frequent due to climate change, it is imperative to develop rice crops that tolerate HNTs. DNA methylation may represent a potential avenue for HNT-tolerant rice strain development, as this mechanism regulates gene activity and cellular phenotype in response to adverse environmental conditions without changing the nucleotide sequence. RESULTS: After HNT exposure, the methylation patterns of cytosines in the CHH context differed noticeably between two coisogenic rice strains with significantly different levels in heat tolerance. Methylation differences between strains were primarily observed on successive cytosines in the promoter or downstream regions of transcription factors and transposon elements. In contrast to the heat-sensitive rice strain, the regions 358-359 bp and 2-60 bp downstream of two basal transcriptional factors (TFIID subunit 11 and mediator of RNA polymerase II transcription subunit 31, respectively) were fully demethylated in the heat-tolerant strain after HNT exposure. In the heat-tolerant strain, HNTs reversed the methylation patterns of successive cytosines in the promoter regions of various genes involved in abscisic acid (ABA)-related reactive oxygen species (ROS) equilibrium pathways, including the pentatricopeptide repeat domain gene PPR (LOC_Os07g28900) and the homeobox domain gene homeobox (LOC_Os01g19694). Indeed, PRR expression was inhibited in heat-sensitive rice strains, and the methylation rates of the cytosines in the promoter region of PRR were greater in heat-sensitive strains as compared to heat-tolerant strains. CONCLUSIONS: After HNT exposure, cytosines in the CHH context were more likely than cytosines in other contexts to be methylated differently between the heat-sensitive and heat-tolerant rice strains. Methylation in the promoter regions of the genes associated with ABA-related oxidation and ROS scavenging improved heat tolerance in rice. Our results help to clarify the molecular mechanisms underlying rice heat tolerance.