In Vitro Preventive Effect and Mechanism of Action of Weissella cibaria CMU against Streptococcus mutans Biofilm Formation and Periodontal Pathogens.

In this study, we evaluated the in vitro anti-biofilm, antibacterial, and anti-inflammatory activity of Weissella cibaria CMU (CMU), an oral probiotic, against periodontopathogens. Compared to other oral probiotics, CMU showed a superior inhibitory effect on the biofilm formation and growth of Streptococcus mutans on orthodontic wires and artificial teeth (p < 0.05). CMU exerted potent antibacterial effects against S. mutans and Porphyromonas gingivalis according to a line test. In human gingival fibroblasts (HGFs) stimulated by P. gingivalis, Fusobacterium nucleatum, or Prevotella intermedia, CMU suppressed the gene expression of pro-inflammatory cytokines [interleukin (IL)-6, IL-1ß, IL-8, and tumor necrosis factor-α] in a dose-dependent manner (p < 0.05). CMU restored the production of the tissue inhibitor of metalloproteinase-1 following its inhibition by P. gingivalis, and it suppressed the expression of matrix metalloproteinase (MMP)-1 and -3 induced by periodontopathogens (p < 0.05). Moreover, CMU needed direct contact with HGFs to exert their anti-inflammatory function, indicating that they act directly on gingival cells to modulate local inflammation. Our preclinical study provides evidence for the potential benefits of topical CMU treatments in preventing the development of caries and periodontitis caused by the dysbiosis of the dental plaque microbiome.

Nuclear OsFKBP20-1b maintains SR34 stability and promotes the splicing of retained introns upon ABA exposure in rice.

Alternative splicing (AS) is a critical means by which plants respond to changes in the environment, but few splicing factors contributing to AS have been reported and functionally characterized in rice (Oryza sativa L.). Here, we explored the function and molecular mechanism of the spliceosome-associated protein OsFKBP20-1b during AS. We determined the AS landscape of wild-type and osfkbp20-1b knockout plants upon abscisic acid (ABA) treatment by transcriptome deep sequencing. To capture the dynamics of translating intron-containing mRNAs, we blocked transcription with cordycepin and performed polysome profiling. We also analyzed whether OsFKBP20-1b and the splicing factors OsSR34 and OsSR45 function together in AS using protoplast transfection assays. We show that OsFKBP20-1b interacts with OsSR34 and regulates its stability, suggesting a role as a chaperone-like protein in the spliceosome. OsFKBP20-1b facilitates the splicing of mRNAs with retained introns after ABA treatment; some of these mRNAs are translatable and encode functional transcriptional regulators of stress-responsive genes. In addition, interacting proteins, OsSR34 and OsSR45, regulate the splicing of the same retained introns as OsFKBP20-1b after ABA treatment. Our findings reveal that spliceosome-associated immunophilin functions in alternative RNA splicing in rice by positively regulating the splicing of retained introns to limit ABA response.

Computerized Version of the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children (KSADS-COMP): Development and Validation of the Korean Clinician-Administered Version.

OBJECTIVE: The purpose of the present study was to develop and validate the Korean version of the clinician-administered KSADSCOMP, which is the recently updated, web-based computerized version of the Kiddie Schedule for Affective Disorders and Schizophrenia for school-age children (KSADS). METHODS: A total of 71 participants (mean age=12.04±3.86 years, female=29.57%) participated in the study. A child-adolescent psychiatrist established a diagnosis for the participant after a thorough psychiatric interview with the participant and the parent. Researchers who were blind to the diagnoses administered the clinician-administered KSADS-COMP to the parents and participants. The gold-standard diagnoses made by child-adolescent psychiatrists were compared to the current diagnoses generated by the clinician-administered KSADS-COMP. Percent agreement, Cohen's Kappa, Gwet's first-order agreement coefficient (AC1), sensitivity, specificity, positive predictive value, and negative predictive value were calculated. RESULTS: Gwet's AC1, our preferred measure of agreement, showed excellent range between 0.78 and 1. Sensitivity, specificity, positive predicted value and negative predictive value also showed high scores. CONCLUSION: The current study demonstrated excellent criterion validity of the Korean version of the clinician-administered KSADSCOMP, though the small sample size could be a limitation. The current study was the first study to examine the criterion validity of the KSADS-COMP. Due to its readily usable format and efficient and accurate diagnostic process, widely-use of KSADS-COMP is expected.

Effects of TSA, NaB, Aza in Lactuca sativa L. protoplasts and effect of TSA in Nicotiana benthamiana protoplasts on cell division and callus formation.

Whole-plant regeneration via plant tissue culture is a complex process regulated by several genetic and environmental conditions in plant cell cultures. Recently, epigenetic regulation has been reported to play an important role in plant cell differentiation and establishment of pluripotency. Herein, we tested the effects of chemicals, which interfere with epigenetic regulation, on the plant regeneration from mesophyll protoplasts of lettuce. The used chemicals were histone deacetylase inhibitors trichostatin A (TSA) and sodium butyrate (NaB), and the DNA methyltransferase inhibitor azacytidine (Aza). All three chemicals increased cell division, micro-callus formation and callus proliferation in lettuce protoplasts. Cell division increased by more than 20% with an optimal treatment of the three chemicals. In addition, substantial increase in the callus proliferation rates was observed. In addition, TSA enhances cell division and adventitious shoot formation in the protoplast culture of Nicotiana benthamiana. The regenerated tobacco plants from TSA-treated protoplasts did not show morphological changes similar to the control. TSA increased histone H3 acetylation levels and affected the expression of CDK, CYCD3-1, and WUS in tobacco protoplasts. Thus, we investigated the effect of TSA, NaB, and Aza on Lactuca sativa L. protoplasts and the effect of TSA on cell division and callus formation in Nicotiana benthamiana protoplasts, which facilitates plant regeneration from mesophyll protoplasts. Furthermore, these chemicals can be directly applied as media additives for efficient plant regeneration and crop improvement in various plant species.

Cyclo[2]carbazole[2]pyrrole: a preorganized calix[4]pyrrole analogue.

A cyclo[2]carbazole[2]pyrrole (2) consisting of two carbazoles and two pyrroles has been synthesized by directly linking the carbazole 1- and 8-carbon atoms to the pyrrole α-carbon atoms. Macrocycle 2 is an extensively conjugated 16-membered macrocyclic ring that is fixed in a pseudo-1,3-alternate conformation. This provides a preorganized anion binding site consisting of two pyrrole subunits. 1H NMR spectroscopic analysis revealed that only the two diagonally opposed pyrrole NH protons, as opposed to the carbazole protons, take part in anion binding. Nevertheless, cyclo[2]carbazole[2]pyrrole 2 binds representative anions with higher affinity in CD2Cl2 than calix[4]pyrrole (1), a well-studied non-conjugated tetrapyrrole macrocycle that binds anions via four pyrrolic NH hydrogen bond interactions. On the basis of computational studies, the higher chloride anion affinity of receptor 2 relative to 1 is rationalized in terms of a larger binding energy and a lower host strain energy associated with anion complexation. In the presence of excess fluoride or bicarbonate anions, compound 2 loses two pyrrolic NH protons to produce a stable dianionic macrocycle [2-2H]2- displaying a quenched fluorescence.

The spliceophilin CYP18-2 is mainly involved in the splicing of retained introns under heat stress in Arabidopsis.

Peptidyl-prolyl isomerase-like 1 (PPIL1) is associated with the human spliceosome complex. However, its function in pre-mRNA splicing remains unclear. In this study, we show that Arabidopsis thaliana CYCLOPHILIN 18-2 (AtCYP18-2), a PPIL1 homolog, plays an essential role in heat tolerance by regulating pre-mRNA splicing. Under heat stress conditions, AtCYP18-2 expression was upregulated in mature plants and GFP-tagged AtCYP18-2 redistributed to nuclear and cytoplasmic puncta. We determined that AtCYP18-2 interacts with several spliceosome complex BACT components in nuclear puncta and is primarily associated with the small nuclear RNAs U5 and U6 in response to heat stress. The AtCYP18-2 loss-of-function allele cyp18-2 engineered by CRISPR/Cas9-mediated gene editing exhibited a hypersensitive phenotype to heat stress relative to the wild type. Moreover, global transcriptome profiling showed that the cyp18-2 mutation affects alternative splicing of heat stress-responsive genes under heat stress conditions, particularly intron retention (IR). The abundance of most intron-containing transcripts of a subset of genes essential for thermotolerance decreased in cyp18-2 compared to the wild type. Furthermore, the intron-containing transcripts of two heat stress-related genes, HEAT SHOCK PROTEIN 101 (HSP101) and HEAT SHOCK FACTOR A2 (HSFA2), produced functional proteins. HSP101-IR-GFP localization was responsive to heat stress, and HSFA2-III-IR interacted with HSF1 and HSP90.1 in plant cells. Our findings reveal that CYP18-2 functions as a splicing factor within the BACT spliceosome complex and is crucial for ensuring the production of adequate levels of alternatively spliced transcripts to enhance thermotolerance.

Multi-biomarker panel prediction model for diagnosis of pancreatic cancer.

BACKGROUND/PURPOSE: The current study aimed to develop a prediction model using a multi-marker panel as a diagnostic screening tool for pancreatic ductal adenocarcinoma. METHODS: Multi-center cohort of 1991 blood samples were collected from January 2011 to September 2019, of which 609 were normal, 145 were other cancer (colorectal, thyroid, and breast cancer), 314 were pancreatic benign disease, and 923 were pancreatic ductal adenocarcinoma. The automated multi-biomarker Enzyme-Linked Immunosorbent Assay kit was developed using three potential biomarkers: LRG1, TTR, and CA 19-9. Using a logistic regression model on a training data set, the predicted values for pancreatic ductal adenocarcinoma were obtained, and the result was classification into one of the three risk groups: low, intermediate, and high. The five covariates used to create the model were sex, age, and three biomarkers. RESULTS: Participants were categorized into four groups as normal (n = 609), other cancer (n = 145), pancreatic benign disease (n = 314), and pancreatic ductal adenocarcinoma (n = 923). The normal, other cancer, and pancreatic benign disease groups were clubbed into the non-pancreatic ductal adenocarcinoma group (n = 1068). The positive and negative predictive value, sensitivity, and specificity were 94.12, 90.40, 93.81, and 90.86, respectively. CONCLUSIONS: This study demonstrates a significant diagnostic performance of the multi-marker panel in distinguishing pancreatic ductal adenocarcinoma from normal and benign pancreatic disease states, as well as patients with other cancers.

Model-Based Prediction of Acid Suppression and Proposal of a New Dosing Regimen of Fexuprazan in Humans.

Fexuprazan is a potassium-competitive acid blocker (P-CAB). The compounds in this newly developed drug family suppress intragastric acidity. As there are already other acid-suppressing drugs on the market, such as H2 antagonists and proton pump inhibitors (PPIs), it would be informative to compare the biological effects of fexuprazan against another approved drug with the same indication. The drug concentration predicted by the pharmacokinetic (PK) model could serve as an input function for a pharmacodynamic (PD) model. The apparent pharmacokinetics of fexuprazan could be described by a simpler model. However, a physiologically based pharmacokinetic (PBPK) model was developed in a previous study. A one-compartment model was also proposed in the present study. Both the newly suggested model and the previously validated PBPK model were used as input functions of the PD models. Our simulation revealed that the effects of fexuprazan could be effectively simulated by the proposed PK-PD models. A PK-PD model was also proposed for the oral administration of the PPI reference drug esomeprazole. A model-based analysis was then performed for intragastric pH using several dosing methods. The expected pH could be predicted for both drugs under several dosing regimens using the proposed PK-PD models.

The Arabidopsis cyclophilin CYP18-1 facilitates PRP18 dephosphorylation and the splicing of introns retained under heat stress.

In plants, heat stress induces changes in alternative splicing, including intron retention; these events can rapidly alter proteins or downregulate protein activity, producing nonfunctional isoforms or inducing nonsense-mediated decay of messenger RNA (mRNA). Nuclear cyclophilins (CYPs) are accessory proteins in the spliceosome complexes of multicellular eukaryotes. However, whether plant CYPs are involved in pre-mRNA splicing remain unknown. Here, we found that Arabidopsis thaliana CYP18-1 is necessary for the efficient removal of introns that are retained in response to heat stress during germination. CYP18-1 interacts with Step II splicing factors (PRP18a, PRP22, and SWELLMAP1) and associates with the U2 and U5 small nuclear RNAs in response to heat stress. CYP18-1 binds to phospho-PRP18a, and increasing concentrations of CYP18-1 are associated with increasing dephosphorylation of PRP18a. Furthermore, interaction and protoplast transfection assays revealed that CYP18-1 and the PP2A-type phosphatase PP2A B'η co-regulate PRP18a dephosphorylation. RNA-seq and RT-qPCR analysis confirmed that CYP18-1 is essential for splicing introns that are retained under heat stress. Overall, we reveal the mechanism of action by which CYP18-1 activates the dephosphorylation of PRP18 and show that CYP18-1 is crucial for the efficient splicing of retained introns and rapid responses to heat stress in plants.

Engineering of Sulfolobus acidocaldarius for Hemicellulosic Biomass Utilization.

The saccharification of cellulose and hemicellulose is essential for utilizing lignocellulosic biomass as a biofuel. While cellulose is composed of glucose only, hemicelluloses are composed of diverse sugars such as xylose, arabinose, glucose, and galactose. Sulfolobus acidocaldarius is a good potential candidate for biofuel production using hemicellulose as this archaeon simultaneously utilizes various sugars. However, S. acidocaldarius has to be manipulated because the enzyme that breaks down hemicellulose is not present in this species. Here, we engineered S. acidocaldarius to utilize xylan as a carbon source by introducing xylanase and ß-xylosidase. Heterologous expression of ß-xylosidase enhanced the organism's degradability and utilization of xylooligosaccharides (XOS), but the mutant still failed to grow when xylan was provided as a carbon source. S. acidocaldarius exhibited the ability to degrade xylan into XOS when xylanase was introduced, but no further degradation proceeded after this sole reaction. Following cell growth and enzyme reaction, S. acidocaldarius successfully utilized xylan in the synergy between xylanase and ß-xylosidase.

Multi-omics reveals microbiome, host gene expression, and immune landscape in gastric carcinogenesis.

To date, there has been no multi-omic analysis characterizing the intricate relationships between the intragastric microbiome and gastric mucosal gene expression in gastric carcinogenesis. Using multi-omic approaches, we provide a comprehensive view of the connections between the microbiome and host gene expression in distinct stages of gastric carcinogenesis (i.e., healthy, gastritis, cancer). Our integrative analysis uncovers various associations specific to disease states. For example, uniquely in gastritis, Helicobacteraceae is highly correlated with the expression of FAM3D, which has been previously implicated in gastrointestinal inflammation. In addition, in gastric cancer but not in adjacent gastritis, Lachnospiraceae is highly correlated with the expression of UBD, which regulates mitosis and cell cycle time. Furthermore, lower abundances of B cell signatures in gastric cancer compared to gastritis may suggest a previously unidentified immune evasion process in gastric carcinogenesis. Our study provides the most comprehensive description of microbial, host transcriptomic, and immune cell factors of the gastric carcinogenesis pathway.

In vivo study for the hemostatic efficacy and foreign body reaction of a new powder-type polysaccharide hemostatic agent.

PURPOSE: Various hemostatic agents have been introduced in therapy as postoperative bleeding is a poor prognostic factor for postoperative outcomes. These products can be divided into those that directly promote the hemostatic cascade and those that physically form a barrier by absorbing blood. The latter, powder-type hemostatic agents have the advantages of being inexpensive and more absorbable with less foreign body reactions (FBRs) and are applicable to a relatively wide area. This study was conducted to verify the safety and efficacy of a newly invented polysaccharide product (OOZFIX, Theracion Biomedical), which improves blood absorption and hemostatic effects. METHODS: Two separate animal experiments were performed. The first evaluated FBRs histologically at 3 days, 2 weeks, and 4 weeks, after implantation of OOZFIX in rats, and the second compared hemostatic performance of OOZFIX and Arista AH (Bard) in the porcine liver punch biopsy model. RESULTS: We found minimal FBRs in the 3-day group and no reactions in both the 2-week and 4-week groups after implantation of hemostatic agents. The time to hemostasis of OOZFIX was not significantly different from that of Arista AH (median [interquartile range]: 9 [6-10] minutes vs. 8 [6-10] minutes, respectively; P = 0.522). When comparing the serial bleeding grade tendency, there was no statistical difference between OOZFIX and Arista AH (P = 0.656). CONCLUSION: OOZFIX caused a minimal FBR that disappeared within 2 weeks in vivo, and its hemostatic performance was comparable with that of an existing agent, Arista AH. Further clinical studies are required in the future.

Targeted Delivery of Exosomes Armed with Anti-Cancer Therapeutics.

Among extracellular vesicles, exosomes have gained great attention for their role as therapeutic vehicles for delivering various active pharmaceutical ingredients (APIs). Exosomes "armed" with anti-cancer therapeutics possess great potential for an efficient intracellular delivery of anti-cancer APIs and enhanced targetability to tumor cells. Various technologies are being developed to efficiently incorporate anti-cancer APIs such as genetic materials (miRNA, siRNA, mRNA), chemotherapeutics, and proteins into exosomes and to induce targeted delivery to tumor burden by exosomal surface modification. Exosomes can incorporate the desired therapeutic molecules via direct exogenous methods (e.g., electroporation and sonication) or indirect methods by modifying cells to produce "armed" exosomes. The targeted delivery of "armed" exosomes to tumor burden could be accomplished either by "passive" targeting using the natural tropism of exosomes or by "active" targeting via the surface engineering of exosomal membranes. Although anti-cancer exosome therapeutics demonstrated promising results in preclinical studies, success in clinical trials requires thorough validation in terms of chemistry, manufacturing, and control techniques. While exosomes possess multiple advantages over synthetic nanoparticles, challenges remain in increasing the loading efficiency of anti-cancer agents into exosomes, as well as establishing quantitative and qualitative analytical methods for monitoring the delivery of in vivo administered exosomes and exosome-incorporated anti-cancer agents to the tumor parenchyma.

Impact of short-chain fatty acid supplementation on gut inflammation and microbiota composition in a murine colitis model.

Short-chain fatty acids (SCFAs) play a pivotal role in maintaining intestinal homeostasis. We aimed to investigate the effects of SCFA supplementation on gut inflammation and microbiota composition in a murine colitis model. Mice were fed with sodium butyrate or a mixture of SCFAs in the drinking water for 2 weeks, followed by 2% dextran sulfate sodium (DSS) for 7 d. After euthanasia, mouse colons were extracted to examine histological findings. Flow cytometry of the mouse colon tissues was performed to assess T cell differentiation. Changes in gut microbiota were assessed by high-throughput sequencing of the mouse feces. There were no significant differences in weight change, colonic length, or histologic inflammation score between the DSS, butyrate, and SCFA mix groups. However, flow cytometry revealed that both the expression of CD4+Foxp3+ regulatory T cells and of IL-17-producing T cells were increased in the butyrate and SCFA mix groups. Microbial compositions of the butyrate and SCFA mix groups were significantly different from those of the control and DSS groups in principal coordinate analysis. Relative abundances of the phyla Verrucomicrobia and Proteobacteria, species Akkermansia muciniphila and Escherichia fergusonii were increased in the butyrate and SCFA mix groups. Genera Roseburia and Lactobacillus showed a negative correlation with the degree of colitis, whereas genera Escherichia and Mucispirillum showed a positive correlation. SCFA supplementation did not result in a significant reduction in colon inflammation, but it promoted both regulatory T cell and IL-17-producing T cell expression, and increased both protective and aggressive gut microbiota.

Their C-termini divide Brassica rapa FT-like proteins into FD-interacting and FD-independent proteins that have different effects on the floral transition.

Members of the FLOWERING LOCUS T (FT)-like clade of phosphatidylethanolamine-binding proteins (PEBPs) induce flowering by associating with the basic leucine zipper (bZIP) transcription factor FD and forming regulatory complexes in angiosperm species. However, the molecular mechanism of the FT-FD heterocomplex in Chinese cabbage (Brassica rapa ssp. pekinensis) is unknown. In this study, we identified 12 BrPEBP genes and focused our functional analysis on four BrFT-like genes by overexpressing them individually in an FT loss-of-function mutant in Arabidopsis thaliana. We determined that BrFT1 and BrFT2 promote flowering by upregulating the expression of floral meristem identity genes, whereas BrTSF and BrBFT, although close in sequence to their Arabidopsis counterparts, had no clear effect on flowering in either long- or short-day photoperiods. We also simultaneously genetically inactivated BrFT1 and BrFT2 in Chinese cabbage using CRISPR/Cas9-mediated genome editing, which revealed that BrFT1 and BrFT2 may play key roles in inflorescence organogenesis as well as in the transition to flowering. We show that BrFT-like proteins, except for BrTSF, are functionally divided into FD interactors and non-interactors based on the presence of three specific amino acids in their C termini, as evidenced by the observed interconversion when these amino acids are mutated. Overall, this study reveals that although BrFT-like homologs are conserved, they may have evolved to exert functionally diverse functions in flowering via their potential to be associated with FD or independently from FD in Brassica rapa.

The Effect of Suicide Prevention Education on Attitudes Toward Suicide in Police Officers.

OBJECTIVE: This study investigated the effect of suicide prevention education on attitudes toward suicide among police officers. METHODS: We used an anonymous questionnaire for 518 officers and surveyed the demographic profiles and examined attitudes toward suicide utilizing the Attitudes Towards Suicide Scale (ATTS) (1=totally agree, 5=totally disagree). Our study divided participants into two groups, based on whether or not they had received suicide prevention education, and examined the differences in attitudes toward suicide between the groups. RESULTS: Of the total population, 247 (47.7%) officers had received suicide prevention education. The education group thought suicide as a predictable matter, disagreeing significantly more with the ATTS factor 'suicide is unpredictable' (3.36 vs. 3.35; p=0.001) compared with the no education group. Also, the education group more perceived suicide as a cry for help and at the same time disagreed more with the notion 'suicidal thoughts will never disappear' (2.08 vs. 2.26; p=0.025, 3.2 vs. 3.05; p=0.035, respectively). CONCLUSION: Officers with experience in suicide prevention education showed more positive attitude toward suicide and suicide prevention. These findings suggest a need to organize more opportunities of suicide prevention educations, such as making the training mandatory for police officers.

Proteome profile of spleen in rock bream (Oplegnathus fasciatus) naturally infected with rock bream iridovirus (RBIV).

BACKGROUND: Rock bream iridovirus (RBIV) is one of the most dangerous pathogens that causes the highest mortality in the aquaculture of rock bream (Oplegnathus fasciatus). Even though RBIV infection leads to huge economic loss, proteome studies on RBIV-infected rock bream have not been conducted to provide information about the differential protein expression pattern by the host protection system. OBJECTIVE: The purpose of this study was to investigate the protein expression patterns in spleens of rock bream olive after infection by RBIV or mixed infection by RBIV and bacteria. METHODS: Depending on the infection intensity and sampling time point, fish were divided into five groups: uninfected healthy fish at week 0 as the control (0C), heavily infected fish at week 0 (0H), heavily mixed RBIV and bacterial infected fish at week 0 (0MH), uninfected healthy fish at week 3 (3C), and lightly infected fish at week 3 (3L). Proteins were extracted from the spleens of infected rock bream. We used 2-DE analysis with LC-MS/MS to investigate proteome changes in infected rock bream. RESULTS: The results of the LC-MS/MS analyses showed different protein expression profiles after infection. Proteins related to oxygen transport and energy generation, such as hemoglobin, beta-globin, and ATP synthase, were mostly expressed in the infected spleen. Whereas proteins involved in structure and cell movement, such as tubulin, myosin, actin binding proteins, and intermediate filament proteins, were down-regulated in the infected spleens. The protein expression profiles between infection by RBIV and mixed infection by RBIV and bacteria showed similar patterns. CONCLUSIONS: Our results indicated that infection by RBIV or mixed infection by RBIV and bacteria triggered energy generation and oxygen-transport, but cell migration and constructional changes in the spleen were extremely decreased.

SUMO Modification of OsFKBP20-1b Is Integral to Proper Pre-mRNA Splicing upon Heat Stress in Rice.

OsFKBP20-1b, a plant-specific cyclophilin protein, has been implicated to regulate pre-mRNA splicing under stress conditions in rice. Here, we demonstrated that OsFKBP20-1b is SUMOylated in a reconstituted SUMOylation system in E.coli and in planta, and that the SUMOylation-coupled regulation was associated with enhanced protein stability using a less SUMOylated OsFKBP20-1b mutant (5KR_OsFKBP20-1b). Furthermore, OsFKBP20-1b directly interacted with OsSUMO1 and OsSUMO2 in the nucleus and cytoplasm, whereas the less SUMOylated 5KR_OsFKBP20-1b mutant had an impaired interaction with OsSUMO1 and 2 in the cytoplasm but not in the nucleus. Under heat stress, the abundance of an OsFKBP20-1b-GFP fusion protein was substantially increased in the nuclear speckles and cytoplasmic foci, whereas the heat-responsiveness was remarkably diminished in the presence of the less SUMOylated 5KR_OsFKBP20-1b-GFP mutant. The accumulation of endogenous SUMOylated OsFKBP20-1b was enhanced by heat stress in planta. Moreover, 5KR_OsFKBP20-1b was not sufficiently associated with the U snRNAs in the nucleus as a spliceosome component. A protoplast transfection assay indicated that the low SUMOylation level of 5KR_OsFKBP20-1b led to inaccurate alternative splicing and transcription under heat stress. Thus, our results suggest that OsFKBP20-1b is post-translationally regulated by SUMOylation, and the modification is crucial for proper RNA processing in response to heat stress in rice.