👤 Gheeyoung Choe

Angiopoietin-like 4 (Angptl4) is a secreted glycoprotein involved in the regulation of various homeostatic and disease processes. In the intestine, prior studies have suggested protective roles for Angptl4 in inflammation using Angptl4 knockout mouse models; however, phenotypic variability-such as perinatal lethality and intestinal inflammation accompanied by lymphatic defects in only a subset of animals-has complicated the interpretation of its role in intestinal pathogenesis. In this study, the impact of Angptl4 deficiency was examined using a subset of Angptl4 knockout mice that survive postnatally without overt abnormalities. It was found that loss of Angptl4 confers protection against colitis and colitis-associated colorectal tumorigenesis. These protective effects were associated with the alternative activation of anti-inflammatory M2-like macrophages. Similarly, in a genetic model of intestinal tumorigenesis, Angptl4 deficiency resulted in reduced tumor burden and attenuated inflammation, accompanied by increased M2-like macrophages. Analysis of human colorectal cancer data sets further revealed that low ANGPTL4 expression is associated with improved survival outcomes as well as reduced expression of inflammation-related marker genes. Collectively, the findings uncover a previously unrecognized protective effect of Angptl4 deficiency against intestinal pathogenesis via anti-inflammatory mechanisms, suggesting Angptl4 as a potential therapeutic target and prognostic biomarker for colorectal cancer and inflammatory bowel disease. Show less

Amyloid-beta (Aβ) aggregation is the key component of neuritic plaques that drives Alzheimer's disease (AD) progression and cognitive decline. Although synaptic dysfunction strongly correlates with cognitive impairment, its underlying mechanisms remain unclear. Recently, the kynurenine pathway (KP) of tryptophan metabolism has emerged as a key contributor to AD pathology, and xanthurenic acid (XA), a naturally occurring end-product of the KP, has been implicated in neuroprotection. In this study, we investigated the neuroprotective effects of intranasally administered XA in an Aβ-induced AD mouse model. AD-like pathology was induced in mice by intracerebroventricular injection of Aβ Show less

Pancreatic cancer (PC) is a common gastrointestinal malignancy whose initiation and progression may be closely linked to the gut microbiota. Previous research indicates that Scutellaria barbata D. Don and Scleromitrion diffusum (Willd.) R.J. Wang (SB-SD) exhibit diverse biological activities, such as anti-inflammatory, antioxidant, and antitumor effects, though their precise regulatory mechanisms are not fully elucidated. Here, we treated PC cells with SB-SD to assess its impact on cell viability, apoptosis, migration, and cell cycle progression, while Western blotting analyzed the expression of HSP90AA1, MAPK3, p53, CDK1, and p21. We also established a pancreatic cancer xenograft model in nude mice to evaluate the in vivo inhibitory effect of SB-SD on tumor growth. Furthermore, we employed metagenomic sequencing, untargeted metabolomics, and quantitative proteomics to comprehensively profile changes in the gut microbiota, serum metabolites, and differentially expressed proteins, with Western blotting subsequently validating BCKDK, GATM and p53 expression. The results show that SB-SD significantly inhibited PC cell proliferation, promoted apoptosis, and induced S/G2 phase cell cycle arrest, potentially via modulation of the HSP90AA1/MAPK3 signaling pathway. Measurements of tumor volume and weight, complemented by histopathological analysis, confirmed that SB-SD effectively suppressed the growth of PANC-1 xenograft tumors. Integrated multi-omics analyses suggest that the antitumor effects of SB-SD may involve the modulation of key gut microbes like Bacteroides caccae and Lactobacillus, the promotion of choline metabolism, and the regulation of BCKDK and GATM. Together, these findings not only corroborate the direct antitumor activity of SB-SD against pancreatic cancer but also offer novel mechanistic insights by constructing a microbiota-metabolite-protein interaction network. Show less

Lipoprotein(a) [Lp(a)] is a genetically determined risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve stenosis (CAVS), with plasma levels largely unaffected by lifestyle modification or conventional lipid-lowering therapy. Although international guidelines increasingly recognize Lp(a) as a risk-enhancing factor, in many Asian populations thresholds for high Lp(a) and treatment strategies remain undefined. This Korean position paper, developed by the Lp(a) Task Force of the Korean Society of Lipid and Atherosclerosis, presents an evidence-based summary of the pathophysiology, clinical relevance, and therapeutic landscape surrounding Lp(a), with a focus on Korean-specific data. It reviews the genetic architecture of Lp(a), ethnic variability in concentrations, and its mechanistic roles in inflammation, thrombosis, and calcification. Based on large Korean cohorts, a 3-tiered classification is proposed of normal (<30 mg/dL), borderline high (30-49 mg/dL), and high (≥50 mg/dL), harmonizing global thresholds with local data. The document also highlights the limitations of current Lp(a) assays in Korea, and calls for standardized, isoform-insensitive testing. Novel therapeutics, including antisense oligonucleotides, small interfering RNAs, and small molecular inhibitors, have shown promising Lp(a)-lowering effects, with multiple phase 3 trials currently ongoing, or in planning. Given the unmet clinical need, the paper recommends incorporating Lp(a) into cardiovascular risk assessment, and calls for Korean-specific longitudinal studies, national screening strategies, and participation in clinical trials. These efforts will help clarify Lp(a)-associated risk in Korean patients and guide the adoption of future targeted therapies. Show less

Lipoprotein(a) [Lp(a)] is a genetically determined risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve stenosis (CAVS), with plasma levels largely unaffected by lifestyle modification or conventional lipid-lowering therapy. Although international guidelines increasingly recognize Lp(a) as a risk-enhancing factor, in many Asian populations thresholds for high Lp(a) and treatment strategies remain undefined. This Korean position paper, developed by the Lp(a) Task Force of the Korean Society of Lipid and Atherosclerosis, presents an evidence-based summary of the pathophysiology, clinical relevance, and therapeutic landscape surrounding Lp(a), with a focus on Korean-specific data. It reviews the genetic architecture of Lp(a), ethnic variability in concentrations, and its mechanistic roles in inflammation, thrombosis, and calcification. Based on large Korean cohorts, a 3-tiered classification is proposed of normal (<30 mg/dL), borderline high (30-49 mg/dL), and high (≥50 mg/dL), harmonizing global thresholds with local data. The document also highlights the limitations of current Lp(a) assays in Korea, and calls for standardized, isoform-insensitive testing. Novel therapeutics, including antisense oligonucleotides, small interfering RNAs, and small molecular inhibitors, have shown promising Lp(a)-lowering effects, with multiple phase 3 trials currently ongoing, or in planning. Given the unmet clinical need, the paper recommends incorporating Lp(a) into cardiovascular risk assessment, and calls for Korean-specific longitudinal studies, national screening strategies, and participation in clinical trials. These efforts will help clarify Lp(a)-associated risk in Korean patients and guide the adoption of future targeted therapies. Show less

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by amyloid-beta (Aβ) plaque deposition and neurofibrillary tangles, which collectively drive neuroinflammation, synaptic dysfunction, and cognitive decline. Here, we investigated whether a peptide epitope vaccine targeting the Aβ1-10 sequence could mitigate Aβ-induced pathology in AD mouse model. Three Aβ1-10 peptides, i.e. Aβ1-10-N, Aβ1-10-D1H, and Aβ1-10-S8R were synthesized, and Aβ1-10-S8R was further conjugated to ovalbumin (OVA) or keyhole limpet hemocyanin (KLH) to enhance immunogenicity. Among seven treatment groups, Aβ1-10-D1H and Aβ1-10-S8R, particularly when conjugated to OVA or KLH, effectively suppressed Aβ, amyloid-beta precursor protein (APP), and beta-secretase 1 (BACE-1) expression, decreased inflammatory cytokine production by astrocytes and microglia, and increased the levels of key synaptic markers (synaptophysin, synaptosomal-associated protein 23 [SNAP-23], postsynaptic density protein 95 [PSD-95]). Carrier protein conjugation also elevated immunoglobulin G (IgG) levels in the spleen, indicative of a robust humoral response. Taken together, these findings demonstrate that Aβ1-10-based immunization, especially with OVA or KLH conjugation, reduces Aβ-driven neuroinflammation, synaptic dysfunction, and memory deficits, suggesting a promising immunotherapeutic strategy for AD. Show less

Lipolysis of triglyceride-rich lipoproteins by peripheral lipoprotein lipase (LPL) plays an essential role in maintaining systemic cholesterol/lipid homeostasis. Human genetic studies have unequivocally demonstrated that activation of LPL pathway reduces risks for both coronary artery disease (CAD) and type 2 diabetes (T2D). Although sterol regulatory element-binding protein 2 (SREBP2) is well established as the master transcription factor that regulates the hepatic biosynthesis of both cholesterol and fatty acids, whether and how its activity in liver interacts with peripheral LPL pathway remains unknown. Here, it is demonstrated that acute liver-specific depletion of SREBP2 results in divergent effects on the regulation of peripheral LPL activity in mice, depending on the presence or absence of low-density lipoprotein receptors (LDLR). SREBP2 deficiency drastically elevates peripheral LPL activity through downregulation of plasma angiopoietin-related protein 3 (ANGPTL3) levels in LDLR-deficient mice. Moreover, in addition to SREBP2's transcriptional regulation of ANGPTL3, it is found that SREBP2 promotes proteasome-based degradation of ANGPTL3 in the presence of LDLR. Remarkably, acute depletion of hepatic SREBP2 protects against hypercholesterolemia and atherosclerosis, in which atherosclerotic lesions are reduced by 45% compared to control littermates. Taken together, these findings outline a liver-peripheral crosstalk mediated by SREBP2-ANGPTL3-LPL axis and suggest that SREBP2 inhibition can be an effective strategy to tackle homozygous familial hypercholesterolemia (HoFH). Show less

The infarcted heart undergoes irreversible pathological remodeling after reperfusion involving left ventricle dilation and excessive inflammatory reactions in the infarcted heart, frequently leading to fatal functional damage. Extensive attempts have been made to attenuate pathological remodeling in infarcted hearts using cardiac patches and anti-inflammatory drug delivery. In this study, we developed a paintable and adhesive hydrogel patch using dextran-aldehyde (dex-ald) and gelatin, incorporating the anti-inflammatory protein, ANGPTL4, into the hydrogel for sustained release directly to the infarcted heart to alleviate inflammation. We optimized the material composition, including polymer concentration and molecular weight, to achieve a paintable, adhesive hydrogel using 10% gelatin and 5% dex-ald, which displayed in-situ gel formation within 135 s, cardiac tissue-like modulus (40.5 kPa), suitable tissue adhesiveness (4.3 kPa), and excellent mechanical stability. ANGPTL4 was continuously released from the gelatin/dex-ald hydrogel without substantial burst release. The gelatin/dex-ald hydrogel could be conveniently painted onto the beating heart and degraded in vivo. Moreover, in vivo studies using animal models of acute myocardial infarction revealed that our hydrogel cardiac patch containing ANGPTL4 significantly improved heart tissue repair, evaluated by echocardiography and histological evaluation. The heart tissues treated with ANGPTL4-loaded hydrogel patches exhibited increased vascularization, reduced inflammatory macrophages, and structural maturation of cardiac cells. Our novel hydrogel system, which allows for facile paintability, appropriate tissue adhesiveness, and sustained release of anti-inflammatory drugs, will serve as an effective platform for the repair of various tissues, including heart, muscle, and cartilage. Show less

Alzheimer's disease (AD) is a progressive neurodegenerative disorder pathologically characterized by the deposition of amyloid beta (Aβ) plaques and neurofibrillary tangles (NFTs) in the brain. The accumulation of these aggregated proteins causes memory and synaptic dysfunction, neuroinflammation, and oxidative stress. This research study is significant as it aims to assess the neuroprotective properties of vitamin E (VE) analog Trolox in an Aβ Show less

Neuroinflammation includes the activation of immune glial cells in the central nervous system, release pro-inflammatory cytokines, which disrupt normal neural function and contribute to various neurological disorders, including Alzheimer's disease (AD), Parkinson's disease, multiple sclerosis, and stroke. AD is characterized by various factors including amyloidogenesis, synaptic dysfunction, memory impairment and neuroinflammation. Lipopolysaccharide (LPS) constitutes a vital element of membrane of the gram-negative bacterial cell, triggering vigorous neuroinflammation and facilitating neurodegeneration. Lupeol, a naturally occurring pentacyclic triterpene, has demonstrated several pharmacological properties, notably its anti-inflammatory activity. In this study, we evaluated the anti-inflammatory and anti-Alzheimer activity of lupeol in lipopolysaccharide (LPS)-injected mice model. LPS (250ug/kg) was administered intraperitoneally to C57BL/6 N male mice for 1 week to induce neuroinflammation and cognitive impairment. For biochemical analysis, acetylcholinesterase (AChE) assay, western blotting and confocal microscopy were performed. AChE, western blot and immunofluorescence results showed that lupeol treatment (50 mg/kg) along with LPS administration significantly inhibited the LPS-induced activation of neuroinflammatory mediators and cytokines like nuclear factor (NF-κB), tumor necrosis factor (TNF-α), cyclooxygenase (COX-2) and interleukin (IL-1β). Furthermore, we found that LPS-induced systemic inflammation lead to Alzheimer's symptoms as LPS treatment enhances level of amyloid beta (Aβ), amyloid precursor protein (APP), Beta-site APP cleaving enzyme (BACE-1) and hyperphosphorylated Tau (p-Tau). Lupeol treatment reversed the LPS-induced elevated level of Aβ, APP, BACE-1 and p-Tau in the hippocampus, showing anti-Alzheimer's properties. It is also determined that lupeol prevented LPS-induced synaptic dysfunction via enhanced expression of pre-and post-synaptic markers like SNAP-23, synaptophysin and PSD-95. Overall, our study shows that lupeol prevents memory impairment and synaptic dysfunction via inhibition of neuroinflammatory processes. Hence, we suggest that lupeol might be a useful therapeutic agent in prevention of neuroinflammation-induced neurological disorders like AD. Show less

Cerebral organoids (COs) are the most advanced in vitro models that resemble the human brain. The use of COs as a model for Alzheimer's disease (AD), as well as other brain diseases, has recently gained attention. This study aimed to develop a human AD CO model using normal human pluripotent stem cells (hPSCs) that recapitulates the pathological phenotypes of AD and to determine the usefulness of this model for drug screening. We established AD hPSC lines from normal hPSCs by introducing genes that harbor familial AD mutations, and the COs were generated using these hPSC lines. The pathological features of AD, including extensive amyloid-β (Aβ) accumulation, tauopathy, and neurodegeneration, were analyzed using enzyme-linked immunosorbent assay, Amylo-Glo staining, thioflavin-S staining, immunohistochemistry, Bielschowsky's staining, and western blot analysis. The AD COs exhibited extensive Aβ accumulation. The levels of paired helical filament tau and neurofibrillary tangle-like silver deposits were highly increased in the AD COs. The number of cells immunoreactive for cleaved caspase-3 was significantly increased in the AD COs. In addition, treatment of AD COs with BACE1 inhibitor IV, a β-secretase inhibitor, and compound E, a γ-secretase inhibitor, significantly attenuated the AD pathological features. Our model effectively recapitulates AD pathology. Hence, it is a valuable platform for understanding the mechanisms underlying AD pathogenesis and can be used to test the efficacy of anti-AD drugs. Show less

Diffuse midline gliomas with H3 K27-alteration (DMGH3) are lethal and inoperable brain tumors. Although DMGH3s mainly occur in pediatric patients, they have also occurred in adult patients. This study aimed to analyze the clinicopathological significance of targetable genetic alterations in non-pediatric DMGH3. Next-generation sequencing (NGS) was conducted on 18 non-pediatric DMGH3 patients to analyze additional genetic alterations. The median age at diagnosis was 35 years, and the mean follow-up duration was 762 days. Fourteen cases involved the thalamus-hypothalamus (77.8%). Histologic high-grade features (WHO histologic grade ≥ 3) were observed in 11 (61.1%) patients. H3F3A (H3 K27 M) alterations were identified in all 18 patients using immunohistochemistry and NGS. TP53 mutations were found in 11 patients (61.1%), FGFR1 or PIK3CA in 3 (16.7%), ATRX in 6 (33.3%), NF1 in 4 (22.2%), and KRAS or ATM in 1 (5.6%). TP53 mutations were significantly correlated with high-grade histological features and worse overall survival (OS) (P < 0.05). Despite non-pediatric DMGH3 cases exhibiting superior OS compared to pediatric DMGH3 cases, TP53 mutations were associated with poorer OS outcomes. Notably, FGFR1 and PIK3CA mutations, which have been identified as potential targetable genes, were detected. In conclusion, non-pediatric DMGH3s showed predominant tumor localization within the thalamus and improved prognosis compared to those in pediatric cases, with TP53 alterations correlating with high-grade histology and shorter survival. Genetic profiling, particularly identifying targetable mutations like FGFR1 and PIK3CA, could inform personalized treatment strategies and improve patient outcomes. Show less

Alzheimer's disease (AD), is a progressive neurodegenerative disorder that involves the deposition of β-amyloid plaques and the clinical symptoms of confusion, memory loss, and cognitive dysfunction. Despite enormous progress in the field, no curative treatment is available. Therefore, the current study was designed to determine the neuroprotective effects of N-methyl-(2S, 4R)-Trans-4-hydroxy-L-proline (NMP) obtained from Sideroxylon obtusifolium, a Brazilian folk medicine with anti-inflammatory and anti-oxidative properties. Here, for the first time, we explored the neuroprotective role of NMP in the Aβ Show less

Oxidative stress plays an important role in cognitive dysfunctions and is seen in neurodegeneration and Alzheimer's disease (AD). It has been reported that the polyphenolic compound caffeic acid possesses strong neuroprotective and antioxidant effects. The current study was conducted to investigate the therapeutic potential of caffeic acid against amyloid beta (Aβ Show less

This study reports on diffuse leptomeningeal glioneuronal tumor (DL-GNT) in a 29-year-old male. DL-GNT is a rare central nervous system (CNS) tumor mostly seen in children and only few cases have been reported in adult patients. Our patient presented with a chronic headache that lasted for five months. MR imaging showed mild hydrocephalus, multiple rim-enhancing nodular lesions in the suprasellar cistern, diffuse leptomeningeal enhancement in the lumbosacral area, and multiple small non-enhancing cyst-appearing lesions not suppressed on fluid attenuated inversion recovery (FLAIR) images in the bilateral basal ganglia, thalami, and cerebral hemispheres. Under the impression of germ cell tumor with leptomeningeal seeding, the patient underwent trans-sphenoidal tumor removal. DL-GNT was pathologically confirmed and FGFR1 mutation was detected through a next-generation sequencing test. In conclusion, a combination of leptomeningeal enhancement and multiple parenchymal non-enhancing cyst-appearing lesions not suppressed on FLAIR images may be helpful for differential diagnosis despite overlapping imaging features with many other CNS diseases that have leptomeningeal enhancement. Show less

There is a growing evidence that fluctuation in lipid profiles is important in cardiovascular outcomes. We aimed to identify single nucleotide polymorphism (SNP) variants associated with low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) variability in statin-naïve Korean subjects and evaluate their associations with coronary atherosclerosis. In statin-naïve subjects from Gene-Environment of Interaction and phenotype cohort, we performed genome-wide association studies of lipid variability; the discovery (first) and replication (second) sets included 4,287 and 1,086 subjects, respectively. Coronary artery calcium (CAC) score and degree of coronary artery stenosis were used as outcome measures. Cholesterol variability was determined by standard deviation and average successive variability, and significant coronary atherosclerosis was defined as CAC score ≥400 or coronary stenosis ≥70%. Mean HDL-C and LDL-C level were 54 ± 12 and 123 ± 30 mg/dL in the first set and 53 ± 12 and 126 ± 29 mg/dL in the second set. Two SNPs associated with LDL-C variability ( Show less

Background inflammatory status indicators have been reported as prognostic biomarkers of colorectal cancer (CRC). However, since inflammatory interactions with the colon involve various modes of action, the biological mechanism linking inflammation and CRC prognosis has not been fully elucidated. We comprehensively evaluated the predictive roles of the expression and methylation levels of inflammation-related genes for CRC prognosis and their pathophysiological associations. An integrative analysis of 247 patients with stage I-III CRC from The Cancer Genome Atlas was conducted. Lasso-penalized Cox proportional hazards regression (Lasso-Cox) and statistical Cox proportional hazard regression (CPH) were used for the analysis. Models to predict overall survival were designed with respective combinations of clinical variables, including age, sex, stage, gene expression, and methylation. An integrative model combining expression, methylation, and clinical features performed better (median C-index = 0.756) than the model with clinical features alone (median C-index = 0.726). Based on multivariate CPH with features from the best model, the methylation levels of CEP250, RAB21, and TNPO3 were significantly associated with overall survival. They did not share any biological process in functional networks. The 5-year survival rate was 29.8% in the low methylation group of CEP250 and 79.1% in the high methylation group ( Our study results implicate the importance of integrating expression and methylation information along with clinical information in the prediction of survival. CEP250, RAB21, and TNPO3 in the prediction model might have a crucial role in CRC prognosis and further improve our understanding of potential mechanisms linking inflammatory reactions and CRC progression. Show less

Metabolic syndrome (MetS) which is caused by obesity and insulin resistance, is well known for its predictive capability for the risk of type 2 diabetes mellitus and cardiovascular disease. The development of MetS is associated with multiple genetic factors, environmental factors and lifestyle. We performed a genome-wide association study to identify single-nucleotide polymorphism (SNP) related to MetS in large Korean population based samples of 1,362 subjects with MetS and 6,061 controls using the Axiom® Korean Biobank Array 1.0. We replicated the data in another sample including 502 subjects with MetS and 1,751 controls. After adjusting for age and sex, rs662799 located in the APOA5 gene were significantly associated with MetS. 15 SNPs in GCKR, C2orf16, APOA5, ZPR1, and BUD13 were associated with high triglyceride (TG). 14 SNPs in APOA5, ALDH1A2, LIPC, HERPUD1, and CETP, and 2 SNPs in MTNR1B were associated with low high density lipoprotein cholesterol (HDL-C) and high fasting blood glucose respectively. Among these SNPs, 6 TG SNPs: rs1260326, rs1260333, rs1919127, rs964184, rs2075295 and rs1558861 and 11 HDL-C SNPs: rs4775041, rs10468017, rs1800588, rs72786786, rs173539, rs247616, rs247617, rs3764261, rs4783961, rs708272, and rs7499892 were first discovered in Koreans. Additional research is needed to confirm these 17 novel SNPs in Korean population. Show less

The spectrum of genetic variants and their clinical significance of Hypertrophic cardiomyopathy (HCM) have been poorly studied in Asian patients. The objectives of this study were to assess the spectrum of genetic variants and genotype-phenotype relationships within a Korean HCM population. Eighty-nine consecutive unrelated HCM patients were included. All patients underwent genotypic analysis for 23 HCM-associated genes. Clinical parameters including echocardiographic and cardiac magnetic resonance (CMR) parameters were evaluated. A composite of major adverse cardiac and cerebrovascular events was assessed. Genetic variants were detected in 55 of 89 subjects. Pathogenic variants or likely pathogenic variants were identified in 27 of HCM patients in Genetic variants in patients with HCM are relatively common and are associated with adverse clinical events and myocardial fibrosis on CMR. Genotypic analysis may add important information to clinical variables in the assessment of long-term risk for HCM patients. Show less

Various environmental stresses induce reactive oxygen species (ROS), causing deleterious effects on plant cells. Glutathione (GSH), a critical antioxidant, is used to combat ROS. GSH is produced by γ-glutamylcysteine synthetase (γ-ECS) and glutathione synthetase (GS). To evaluate the functional roles of the Oryza sativa L. Japonica cv. Ilmi ECS (OsECS) gene, we generated transgenic rice plants overexpressing OsECS under the control of an inducible promoter (Rab21). When grown under saline conditions (100mM) for 4 weeks, 2-independent transgenic (TGR1 and TGR2) rice plants remained bright green in comparison to control wild-type (WT) rice plants. TGR1 and TGR2 rice plants also showed a higher GSH/GSSG ratio than did WT rice plants in the presence of 100mM NaCl, which led to enhanced redox homeostasis. TGR1 and TGR2 rice plants also showed lower ion leakage and higher chlorophyll-fluorescence when exposed to 10μM methyl viologen (MV). Furthermore, the TGR1 and TGR2 rice seeds had approximately 1.5-fold higher germination rates in the presence of 200mM salt. Under paddy field conditions, OsECS-overexpression in transgenic rice plants increased rice grain yield (TGW) and improved biomass. Overall, our results show that OsECS overexpression in transgenic rice increases tolerance and germination rate in the presence of abiotic stress by improving redox homeostasis via an enhanced GSH pool. Our findings suggest that increases in grain yield by OsECS overexpression could improve crop yields under natural environmental conditions. Show less

Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) play important roles in insulin secretion through their receptors, GLP1R and GIPR. Although GLP-1 and GIP are attractive candidates for treatment of type 2 diabetes and obesity, little is known regarding the molecular interaction of these peptides with the heptahelical core domain of their receptors. These core domains are important not only for specific ligand binding but also for ligand-induced receptor activation. Here, using chimeric and point-mutated GLP1R/GIPR, we determined that evolutionarily conserved amino acid residues such as Ile(196) at transmembrane helix 2, Leu(232) and Met(233) at extracellular loop 1, and Asn(302) at extracellular loop 2 of GLP1R are responsible for interaction with ligand and receptor activation. Application of chimeric GLP-1/GIP peptides together with molecular modeling suggests that His(1) of GLP-1 interacts with Asn(302) of GLP1R and that Thr(7) of GLP-1 has close contact with a binding pocket formed by Ile(196), Leu(232), and Met(233) of GLP1R. This study may provide critical clues for the development of peptide and/or nonpeptide agonists acting at GLP1R. Show less

The dynamic exchange of histone lysine methylation status by histone methyltransferases and demethylases has been previously implicated as an important factor in chromatin structure and transcriptional regulation. Using immunoaffinity TAP analysis, we purified the WHISTLE-interacting protein complexes, which include the heat shock protein HSP90α and the jumonji C-domain harboring the histone demethylase JMJD1C. In this study, we demonstrate that JMJD1C specifically demethylates histone H3K9 mono- and di-methylation, and mediates transcriptional activation. We also provide evidence suggesting that both WHISTLE and JMJD1C performs functions in the development of mouse testes by regulating the expression of the steroidogenesis marker, p450c17, via SF-1-mediated transcription. Furthermore, we demonstrate that WHISTLE is recruited to the p450c17 promoter via SF-1 and represses the transcription of prepubertal stages of steroidogenesis, after which JMJD1C replaces WHISTLE and activates the expression of target genes via SF-1-mediated interactions. Our results demonstrate that the histone methylation balance mediated by HMTase WHISTLE and demethylase JMJD1C perform a transcriptional regulatory function in mouse testis development. Show less