Glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) has been identified in multiple genome-wide association studies (GWAS) as a contributor to obesity, and GIPR knockout mice are protec Show more
Glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) has been identified in multiple genome-wide association studies (GWAS) as a contributor to obesity, and GIPR knockout mice are protected against diet-induced obesity (DIO). On the basis of this genetic evidence, we developed anti-GIPR antagonistic antibodies as a potential therapeutic strategy for the treatment of obesity and observed that a mouse anti-murine GIPR antibody (muGIPR-Ab) protected against body weight gain, improved multiple metabolic parameters, and was associated with reduced food intake and resting respiratory exchange ratio (RER) in DIO mice. We replicated these results in obese nonhuman primates (NHPs) using an anti-human GIPR antibody (hGIPR-Ab) and found that weight loss was more pronounced than in mice. In addition, we observed enhanced weight loss in DIO mice and NHPs when anti-GIPR antibodies were codosed with glucagon-like peptide-1 receptor (GLP-1R) agonists. Mechanistic and crystallographic studies demonstrated that hGIPR-Ab displaced GIP and bound to GIPR using the same conserved hydrophobic residues as GIP. Further, using a conditional knockout mouse model, we excluded the role of GIPR in pancreatic β-cells in the regulation of body weight and response to GIPR antagonism. In conclusion, these data provide preclinical validation of a therapeutic approach to treat obesity with anti-GIPR antibodies. Show less
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have become a powerful tool for human disease modeling and therapeutic testing. However, their use remains limited by their immat Show more
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) have become a powerful tool for human disease modeling and therapeutic testing. However, their use remains limited by their immaturity and heterogeneity. To characterize the source of this heterogeneity, we applied complementary single-cell RNA-seq and bulk RNA-seq technologies over time during hiPSC cardiac differentiation and in the adult heart. Using integrated transcriptomic and splicing analysis, more than half a dozen distinct single-cell populations were observed, several of which were coincident at a single time-point, day 30 of differentiation. To dissect the role of distinct cardiac transcriptional regulators associated with each cell population, we systematically tested the effect of a gain or loss of three transcription factors (NR2F2, TBX5, and HEY2), using CRISPR genome editing and ChIP-seq, in conjunction with patch clamp, calcium imaging, and CyTOF analysis. These targets, data, and integrative genomics analysis methods provide a powerful platform for understanding in vitro cellular heterogeneity. Show less
The overexpression of EGFR often occurs in TNBC, and the anti-EGFR receptor antibody cetuximab is used widely to treat metastatic cancer in the clinic. However, EGFR-targeted therapies have been devel Show more
The overexpression of EGFR often occurs in TNBC, and the anti-EGFR receptor antibody cetuximab is used widely to treat metastatic cancer in the clinic. However, EGFR-targeted therapies have been developed for TNBC without clinical success. In this study, we show that impaired EGFR degradation is crucial for resistance to cetuximab, which depends on the cell surface molecule CD44. To further investigate the role of CD44 in EGFR signaling and its treatment potential, we developed a targeting fusion protein composed of an anti-EGFR scFv generated from cetuximab and truncated protamine, called Ce-tP. CD44 siRNA can be specifically delivered into EGFR-positive TNBC cells by Ce-tP. Efficient knockdown of CD44 and suppression of both EGFR and downstream signaling by the Ce-tP/siRNA complex were observed in EGFR-positive TNBC cells. More importantly, our results also showed that targeted delivery of siRNA specific for CD44 can efficiently overcome resistance to EGFR targeting in TNBC cells both in vitro and in vivo. Overall, our results establish a new principle to achieve EGFR inhibition in TNBC and limit drug resistance. Show less
The progression toward low-cost and rapid next-generation sequencing has uncovered a multitude of variants of uncertain significance (VUS) in both patients and asymptomatic "healthy" individuals. A VU Show more
The progression toward low-cost and rapid next-generation sequencing has uncovered a multitude of variants of uncertain significance (VUS) in both patients and asymptomatic "healthy" individuals. A VUS is a rare or novel variant for which disease pathogenicity has not been conclusively demonstrated or excluded, and thus cannot be definitively annotated. VUS, therefore, pose critical clinical interpretation and risk-assessment challenges, and new methods are urgently needed to better characterize their pathogenicity. To address this challenge and showcase the uncertainty surrounding genomic variant interpretation, we recruited a "healthy" asymptomatic individual, lacking cardiac-disease clinical history, carrying a hypertrophic cardiomyopathy (HCM)-associated genetic variant (NM₀₀₀₂₅₈.2:c.170C>A, NP₀₀₀₂₄₉.1:p.Ala57Asp) in the sarcomeric gene MYL3, reported by the ClinVar database to be "likely pathogenic." Human-induced pluripotent stem cells (iPSCs) were derived from the heterozygous VUS MYL3 The heterozygous VUS MYL3 Our study illustrates the ability of clustered regularly interspaced short palindromic repeats/Cas9 genome-editing of carrier-specific iPSCs to elucidate both benign and pathogenic HCM functional phenotypes in a carrier-specific manner in a dish. As such, this platform represents a promising VUS risk-assessment tool that can be used for assessing HCM-associated VUS specifically, and VUS in general, and thus significantly contribute to the arsenal of precision medicine tools available in this emerging field. Show less
Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease for which the genetic contribution is incompletely understood. We conducted a joint analysis of 5,523,934 imputed SNPs in two n Show more
Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease for which the genetic contribution is incompletely understood. We conducted a joint analysis of 5,523,934 imputed SNPs in two newly-genotyped progressive supranuclear palsy cohorts, primarily derived from two clinical trials (Allon davunetide and NNIPPS riluzole trials in PSP) and a previously published genome-wide association study (GWAS), in total comprising 1646 cases and 10,662 controls of European ancestry. We identified 5 associated loci at a genome-wide significance threshold P < 5 × 10 In total, we identified 6 additional significant or suggestive SNP associations with PSP, and discovered genetic overlap with other neurodegenerative diseases. These findings clarify the pathogenesis and genetic architecture of PSP. Show less
Hereditary channelopathies and cardiomyopathies are potentially lethal and are clinically and genetically heterogeneous, involving at least 90 genes. Genetic testing can provide an accurate diagnosis, Show more
Hereditary channelopathies and cardiomyopathies are potentially lethal and are clinically and genetically heterogeneous, involving at least 90 genes. Genetic testing can provide an accurate diagnosis, guide treatment, and enable cascade screening. The genetic basis among the Hong Kong Chinese population is largely unknown. We aimed to report on 28 unrelated patients with positive genetic findings detected from January 2006 to December 2015. Sanger sequencing was performed for 28 unrelated patients with a clinical diagnosis of channelopathies or cardiomyopathies, testing for the following genes: There were 17 males and 11 females; their mean age at diagnosis was 39 years (range, 1-80 years). The major clinical presentations included syncope, palpitations, and abnormal electrocardiography findings. A family history was present in 13 (46%) patients. There were 26 different heterozygous mutations detected, of which six were novel-two in We have characterised the genetic heterogeneity in channelopathies and cardiomyopathies among Hong Kong Chinese patients in a 10-year case series. Correct interpretation of genetic findings is difficult and requires expertise and experience. Caution regarding issues of non-penetrance, variable expressivity, phenotype-genotype correlation, susceptibility risk, and digenic inheritance is necessary for genetic counselling and cascade screening. Show less
To assess the association of genes in the high-density lipoprotein metabolic pathway (HDLMP) with polypoidal choroidal vasculopathy (PCV) and the genetic difference in the HDLMP between PCV and age-re Show more
To assess the association of genes in the high-density lipoprotein metabolic pathway (HDLMP) with polypoidal choroidal vasculopathy (PCV) and the genetic difference in the HDLMP between PCV and age-related macular degeneration (AMD). We performed a literature search in EMBASE, PubMed, and Web of Science for genetic studies on 7 single nucleotide polymorphisms (SNPs) from 5 genes in the HDLMP including cholesteryl ester transfer protein (CETP), hepatic lipase (LIPC), lipoprotein lipase (LPL), ATP-binding cassette transporter A1 (ABCA1), and ATP-binding cassette transporter G1 (ABCG1) in PCV. All studies were published before September 30, 2017, without language restriction. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) of each polymorphism were estimated. We also compared the association profiles between PCV and AMD and performed a sensitivity analysis. Our result is based on 43 articles. After excluding duplicates and articles without complete information, 7 studies were applicable to meta-analysis. 7 polymorphisms were meta-analyzed: CETP rs2303790/rs3764261, LIPC rs10468017/rs493258, LPL rs12678919, ABCA1 rs1883025, and ABCG1 rs57137919. We found that in Asian population, CETP rs3764261 (T allele; OR = 1.46; 95% CI: 1.28-1.665, Our study revealed 7 polymorphisms in 5 genes. Among them, CETP (rs3764261/rs2303790) and ABCG1 (rs57137919) were the major susceptibility genes for PCV in Asian population and ABCG1 (rs57137919) showed allelic diversity between PCV and AMD. Since the size for PCV and AMD was small, we need to study these genes genotyping in larger samples. Show less
We report the generation of the human iPSC line LEIi004-A from a patient with late-onset non-syndromic retinitis pigmentosa caused by compound heterozygous mutations in the CLN3 gene. Reprogramming of Show more
We report the generation of the human iPSC line LEIi004-A from a patient with late-onset non-syndromic retinitis pigmentosa caused by compound heterozygous mutations in the CLN3 gene. Reprogramming of primary dermal fibroblasts was performed using episomal plasmids containing OCT4, SOX2, KLF4, L-MYC, LIN28, shRNA for p53 and mir302/367 microRNA. To create a coisogenic control line, one CLN3 variant was corrected in the patient-iPSC using CRISPR/Cas9 gene editing to generate the iPSC line LEIi004-A-1. Show less
Platelet αIIbβ3 integrin and its ligands are essential for thrombosis and hemostasis, and play key roles in myocardial infarction and stroke. Here we show that apolipoprotein A-IV (apoA-IV) can be iso Show more
Platelet αIIbβ3 integrin and its ligands are essential for thrombosis and hemostasis, and play key roles in myocardial infarction and stroke. Here we show that apolipoprotein A-IV (apoA-IV) can be isolated from human blood plasma using platelet β3 integrin-coated beads. Binding of apoA-IV to platelets requires activation of αIIbβ3 integrin, and the direct apoA-IV-αIIbβ3 interaction can be detected using a single-molecule Biomembrane Force Probe. We identify that aspartic acids 5 and 13 at the N-terminus of apoA-IV are required for binding to αIIbβ3 integrin, which is additionally modulated by apoA-IV C-terminus via intra-molecular interactions. ApoA-IV inhibits platelet aggregation and postprandial platelet hyperactivity. Human apoA-IV plasma levels show a circadian rhythm that negatively correlates with platelet aggregation and cardiovascular events. Thus, we identify apoA-IV as a novel ligand of αIIbβ3 integrin and an endogenous inhibitor of thrombosis, establishing a link between lipoprotein metabolism and cardiovascular diseases. Show less
In the human body, 50-70 billion cells die every day, resulting in the generation of a large number of apoptotic bodies. However, the detailed biological role of apoptotic bodies in regulating tissue Show more
In the human body, 50-70 billion cells die every day, resulting in the generation of a large number of apoptotic bodies. However, the detailed biological role of apoptotic bodies in regulating tissue homeostasis remains unclear. In this study, we used Fas-deficient MRL/lpr and Caspase 3 Show less
Diabetic retinopathy (DR) is a major cause of adult blindness. Retinal Müller cells maintain water homeostasis and potassium concentration via inwardly rectifying Kir4.1 channels. Accumulation of adva Show more
Diabetic retinopathy (DR) is a major cause of adult blindness. Retinal Müller cells maintain water homeostasis and potassium concentration via inwardly rectifying Kir4.1 channels. Accumulation of advanced glycation end products (AGEs) is a major pathologic event in DR. While diabetes leads to a decrease in the Kir4.1 channels, it remains unknown whether AGEs-linked to the basement membrane (BM) affect normal Kir4.1 channels. For this study, we hypothesized that AGE-modification of laminin is detrimental to Kir4.1 channels, therefore, disrupting Müller cell function. The AGE-modified laminin-coated substrates were prepared by incubating Petri-dishes with laminin and methylglyoxal for seven days. The rat Müller cells (rMC-1) were propagated on AGE-modified laminin, and Kir4.1 expression and function were evaluated. Quantification of AGEs using ELISA revealed a dose-dependent increase in methylglyoxal-hydro-imidazolone adducts. The rMC-1 propagated on AGE-modified laminin demonstrated a decrease in Kir4.1 levels in immunofluorescence and western blot studies and a decrease in the Kir4.1 channel function. Kir4.1 decrease on AGE-modified laminin resulted in a disorganization of an actin cytoskeleton and disruption of α-dystroglycan-syntrophin-dystrophin complexes. Our studies suggest that AGE-modification of laminin is detrimental to Kir4.1 channels. By studying the role of AGEs in Kir4.1 channels we have identified a novel mechanism of Müller cell dysfunction and its subsequent involvement in DR. Show less
Colorectal cancer (CRC) is one of the most common malignant gastrointestinal cancers. Metastasis is a major leading of death in patients with CRC and many patients have metastatic disease at diagnosis Show more
Colorectal cancer (CRC) is one of the most common malignant gastrointestinal cancers. Metastasis is a major leading of death in patients with CRC and many patients have metastatic disease at diagnosis. However, the underlying molecular mechanisms are still elusive. Here, we showed that JMJD1C was overexpressed in colon cancer tissues compared to normal samples and was positively associated with metastasis and poor prognosis. Silencing JMJD1C strongly inhibits CRC migration and invasion both in vitro and in vivo. Further, we found that knockdown of JMJD1C decreased the protein and mRNA levels of ATF2, mechanistically, and JMJD1C regulated the expression of ATF2 by modulating the H3K9me2 but not H3K9me1 activity. In addition, we further performed some "rescues experiments". We found that overexpression of ATF2 could reverse the abrogated migration and invasion ability by knockdown of JMJD1C in CRC. Our results demonstrated that an increase of JMJD1C was observed in colon cancer and knockdown of JMJD1C regulated CRC metastasis by inactivation of the ATF2 pathway. This novel JMJD1C/ATF2 signaling pathway may be a promising therapeutic target for CRC metastasis. Show less
Angiopoietin-like 4 (ANGPTL4) is an endogenous inhibitor of lipoprotein lipase that modulates lipid levels, coronary atherosclerosis risk, and nutrient partitioning. We hypothesize that loss of ANGPTL Show more
Angiopoietin-like 4 (ANGPTL4) is an endogenous inhibitor of lipoprotein lipase that modulates lipid levels, coronary atherosclerosis risk, and nutrient partitioning. We hypothesize that loss of ANGPTL4 function might improve glucose homeostasis and decrease risk of type 2 diabetes (T2D). We investigate protein-altering variants in ANGPTL4 among 58,124 participants in the DiscovEHR human genetics study, with follow-up studies in 82,766 T2D cases and 498,761 controls. Carriers of p.E40K, a variant that abolishes ANGPTL4 ability to inhibit lipoprotein lipase, have lower odds of T2D (odds ratio 0.89, 95% confidence interval 0.85-0.92, p = 6.3 × 10 Show less
Helicase DHX36 plays essential roles in cell development and differentiation at least partially by resolving G-quadruplex (G4) structures. Here we report crystal structures of the Drosophila homolog o Show more
Helicase DHX36 plays essential roles in cell development and differentiation at least partially by resolving G-quadruplex (G4) structures. Here we report crystal structures of the Drosophila homolog of DHX36 (DmDHX36) in complex with RNA and a series of DNAs. By combining structural, small-angle X-ray scattering, molecular dynamics simulation, and single-molecule fluorescence studies, we revealed that positively charged amino acids in RecA2 and OB-like domains constitute an elaborate structural pocket at the nucleic acid entrance, in which negatively charged G4 DNA is tightly bound and partially destabilized. The G4 DNA is then completely unfolded through the 3'-5' translocation activity of the helicase. Furthermore, crystal structures and DNA binding assays show that G-rich DNA is preferentially recognized and in the presence of ATP, specifically bound by DmDHX36, which may cooperatively enhance the G-rich DNA translocation and G4 unfolding. On the basis of these results, a conceptual G4 DNA-resolving mechanism is proposed. Show less
Gastric cancer (GC) is one of the most common cancers and is the second-leading cause of cancer-associated morbidity worldwide. Oxysterols are oxidized derivatives of cholesterol that may be important Show more
Gastric cancer (GC) is one of the most common cancers and is the second-leading cause of cancer-associated morbidity worldwide. Oxysterols are oxidized derivatives of cholesterol that may be important in many biological processes, but the levels and roles of oxysterols in gastric tumours remain to be elucidated. The levels of cholesterol, oxysterols and sulfated oxysterols in human gastric tumour tissues, adjacent normal mucosal tissues, cancerous gastric juice and gastric juice obtained from healthy subjects were detected by LC-MS. It was found that the levels of 24(R/S),25-EC and 27HC in human gastric tumour tissues and cancerous gastric juice were significantly increased compared with those of adjacent normal mucosal tissues and gastric juice from healthy subjects. Compared with normal gastric mucosal tissue, the levels of sulfated 25-hydroxycholesterol (25HC3S) and the ratio of 25HC3S/25HC were decreased in human gastric tumour tissues, which might be related to the dramatically decreased SULT2A1 expression in gastric tumour tissue. Both 24(R/S),25-EC and 27HC suppressed gastric cancer proliferation, which was not altered by LXRα-siRNA treatment. The suppression of cell proliferation induced by 27HC was attenuated by LXRβ-siRNA, but the suppression of cell proliferation induced by 24(R/S),25-EC was intensified by LXRβ-siRNA. Both 24(R/S),25-EC and 27HC dramatically inhibited HGC-27 cell migration, which was attenuated by the co-transfection of cells with LXRα-siRNA and LXRβ-siRNA, but not LXRα-siRNA or LXRβ-siRNA alone. In conclusion, the accumulated 24(R/S),25-EC and 27HC in human gastric tumour tissues might play important roles in gastric cancer development. Show less
The hypothalamic melanocortin 4 receptor (MC4R) pathway serves a critical role in regulating body weight. Loss of function (LoF) mutations in the MC4R pathway, including mutations in the pro-opiomelan Show more
The hypothalamic melanocortin 4 receptor (MC4R) pathway serves a critical role in regulating body weight. Loss of function (LoF) mutations in the MC4R pathway, including mutations in the pro-opiomelanocortin (POMC), prohormone convertase 1 (PCSK1), leptin receptor (LEPR), or MC4R genes, have been shown to cause early-onset severe obesity. Through a comprehensive epidemiological analysis of known and predicted LoF variants in the POMC, PCSK1, and LEPR genes, we sought to estimate the number of US individuals with biallelic MC4R pathway LoF variants. We predict ~650 α-melanocyte-stimulating hormone (MSH)/POMC, 8500 PCSK1, and 3600 LEPR homozygous and compound heterozygous individuals in the United States, cumulatively enumerating >12,800 MC4R pathway-deficient obese patients. Few of these variants have been genetically diagnosed to date. These estimates increase when we include a small subset of less rare variants: β-MSH/POMC,PCSK1 N221D, and a PCSK1 LoF variant (T640A). To further define the MC4R pathway and its potential impact on obesity, we tested associations between body mass index (BMI) and LoF mutation burden in the POMC, PCSK1, and LEPR genes in various populations. We show that the cumulative allele burden in individuals with two or more LoF alleles in one or more genes in the MC4R pathway are predisposed to a higher BMI than noncarriers or heterozygous LoF carriers with a defect in only one gene. Our analysis represents a genetically rationalized study of the hypothalamic MC4R pathway aimed at genetic patient stratification to determine which obese subpopulations should be studied to elucidate MC4R agonist (e.g., setmelanotide) treatment responsiveness. Show less
To characterize the association between epilepsy, use of antiepileptic drugs (AEDs), and the risk of hyperlipidemia, we conducted a nationwide population-based cohort study with data obtained from the Show more
To characterize the association between epilepsy, use of antiepileptic drugs (AEDs), and the risk of hyperlipidemia, we conducted a nationwide population-based cohort study with data obtained from the National Health Insurance Research Database of Taiwan. The effects of AEDs on lipogenic gene expression were also examined in vitro. We identified 3617 cases involving patients, whose epilepsy was newly diagnosed between 2000 and 2011, and selected a comparison cohort comprising 14,468 patients without epilepsy. The Cox proportional hazards model was used to evaluate the association between epilepsy, AED use, and hyperlipidemia. The incidence rate of hyperlipidemia was higher in the epilepsy cohort than in the comparison cohort, with an adjusted hazard ratio (aHR) of 1.21 [95% confidence interval (CI): 1.06-1.38] after adjusting for comorbidities and medications. Epilepsy patients not taking AEDs had a higher risk of hyperlipidemia (aHR 1.65; 95% CI 1.35-2.03). Among AEDs, only valproate treatment showed a higher risk of hyperlipidemia (aHR 1.53; 95% CI 1.01-2.33), although the dose-dependent effect did not reach statistical significance. In vitro studies with two hepatic cell lines showed that valproate may exert its effects by activating the liver X receptor alpha (LXRα) signaling pathway, inducing the expression of lipogenesis-related genes and increasing cellular lipid contents. In silico calculations concluded that valproate can bind stably with the ligand-binding domain of LXRα. Thus, valproate-induced hepatic lipogenic gene expression may occur through LXRα activation. Predicting the 'off-target' effects of valproate may prove valuable in developing antiepileptic agents with fewer adverse reactions. Monitoring blood lipid levels throughout the course of treatment is recommended. Show less
Carbamoyl Phosphate Synthetase 1 deficiency (CPS1D) is a rare autosomal recessive inborn metabolic disease characterized mainly by hyperammonemia. The fatal nature of CPS1D and its similar symptoms wi Show more
Carbamoyl Phosphate Synthetase 1 deficiency (CPS1D) is a rare autosomal recessive inborn metabolic disease characterized mainly by hyperammonemia. The fatal nature of CPS1D and its similar symptoms with other urea cycle disorders (UCDs) make its diagnosis difficult, and the molecular diagnosis is hindered due to the large size of the causative gene CPS1. Therefore, the objective of the present study was to investigate the clinical applicability of exome sequencing in molecular diagnosis of CPS1D in Chinese population. We described two Chinese neonates presented with unconsciousness and drowsiness due to deepening encephalopathy with hyperammonemia. Whole exome sequencing was performed. Candidate mutations were validated by Sanger sequencing. In-silicon analysis was processed for the pathogenicity predictions of the identified mutations. Two compound heterozygous mutations in the gene carbamoyl phosphate synthetase 1(CPS1) were identified. One is in Case 1 with two novel missense mutations (c.2537C>T, p. Pro846Leu and c.3443T>A, p.Met1148Lys), and the other one is in Case 2 with a novel missense mutation (c.1799G>A, p.Cys600Tyr) and a previously reported 12-bp deletion (c.4088₄₀₉₉del, p.Leu 1363_Ile1366del). Bioinformatics deleterious predictions indicated pathogenicity of the missense mutations. Conversation analysis and homology modeling showed that the substituted amino acids were highly evolutionary conserved and necessary for enzyme stability or function. The present study initially and successfully applied whole exome sequencing to the molecular diagnosis of CPS1D in Chinese neonates, indicating its applicability in cost-effective molecular diagnosis of CPS1D. Three novel pathogenic missense mutations were identified, expanded the mutational spectrum of the CPS1 gene. Show less
We previously showed that complement 3 (C3) is highly expressed in mesenchymal tissues in spontaneously hypertensive rats (SHR). We targeted C3 gene by zinc-finger nuclease (ZFN) gene-editing technolo Show more
We previously showed that complement 3 (C3) is highly expressed in mesenchymal tissues in spontaneously hypertensive rats (SHR). We targeted C3 gene by zinc-finger nuclease (ZFN) gene-editing technology and investigated blood pressure and phenotype in SHR. Blood pressure was measured by tail-cuff and telemetry methods. Histology and expression of liver X receptor α (LXRα), renin, Krüppel-like factor 5 (KLF5), and E-cadherin were evaluated in kidneys. Mesangial cells (MCs) were removed from glomeruli from three strains, and we evaluated the phenotype in vitro. SHR showed the salt-sensitive hypertension that was abolished in C3 knockout (KO) SHR. Proliferation of MCs from SHR was higher than that from Wistar-Kyoto (WKY) rats and showed a synthetic phenotype. Renal injury scores were higher in SHR than in WKY rats and C3 KO SHR. Expression of E-cadherin was lower, and expression of renin was higher in the nephrotubulus from SHR than WKY rats and C3 KO SHR. Expression of C3 α-chain protein and α-smooth muscle actin protein was significantly higher in renal medulla from SHR than from WKY rats. Expression of angiotensinogen, LXRα, renin, and KLF5 mRNA was increased in kidney from SHR compared with C3 KO SHR. Intrarenal angiotensin II levels were significantly higher in kidney from SHR than WKY rats and C3 KO SHR. Urinary epinephrine and norepinephrine excretions were significantly higher in SHR than in WKY rats and C3 KO SHR. These findings showed that increased C3 induces salt-sensitive hypertension with increases in urinary catecholamine excretion and intrarenal activation of the renin-angiotensin system by the dedifferentiation of mesenchymal tissues in kidney from SHR. Show less
γ-Secretase has been a therapeutical target for its key role in cleaving APP to generate β-amyloid (Aβ), the primary constituents of senile plaques and a hallmark of Alzheimer's disease (AD) pathology Show more
γ-Secretase has been a therapeutical target for its key role in cleaving APP to generate β-amyloid (Aβ), the primary constituents of senile plaques and a hallmark of Alzheimer's disease (AD) pathology. Recently, γ-secretase-associating proteins showed promising role in specifically modulating APP processing while sparing Notch signaling; however, the underlying mechanism is still unclear. A co-immunoprecipitation (Co-IP) coupled with mass spectrometry proteomic assay for Presenilin1 (PS1, the catalytic subunit of γ-secretase) was firstly conducted to find more γ-secretase-associating proteins. Gene ontology analysis of these results identified Rab21 as a potential PS1 interacting protein, and the interaction between them was validated by reciprocal Co-IP and immunofluorescence assay. Then, molecular and biochemical methods were used to investigate the effect of Rab21 on APP processing. Results showed that overexpression of Rab21 enhanced Aβ generation, while silencing of Rab21 reduced the accumulation of Aβ, which resulted due to change in γ-secretase activity rather than α- or β-secretase. Finally, we demonstrated that Rab21 had no effect on γ-secretase complex synthesis or metabolism but enhanced PS1 endocytosis and translocation to late endosome/lysosome. In conclusion, we identified a novel γ-secretase-associating protein Rab21 and illustrate that Rab21 promotes γ-secretase internalization and translocation to late endosome/lysosome. Moreover, silencing of Rab21 decreases the γ-secretase activity in APP processing thus production of Aβ. All these results open new gateways towards the understanding of γ-secretase-associating proteins in APP processing and make inhibition of Rab21 a promising strategy for AD therapy. Show less
Jia Wang, Jianhua Gong, Li Li+7 more · 2018 · Autism research : official journal of the International Society for Autism Research · Wiley · added 2026-04-24
Increasing evidence suggests that abnormal synaptic function leads to neuronal developmental disorders and is an important component of the etiology of autism spectrum disorder (ASD). Neurexins are pr Show more
The class III PI3-kinase (PIK3C3) is an enzyme responsible for the generation of phosphatidylinositol 3-phosphate (PI3P), a critical component of vesicular membrane. Here, we report that PIK3C3 defici Show more
The class III PI3-kinase (PIK3C3) is an enzyme responsible for the generation of phosphatidylinositol 3-phosphate (PI3P), a critical component of vesicular membrane. Here, we report that PIK3C3 deficiency in zebrafish results in intestinal injury and inflammation. In pik3c3 mutants, gut tube forms but fails to be maintained. Gene expression analysis reveals that barrier-function-related inflammatory bowel disease (IBD) susceptibility genes (e-cadherin, hnf4a, ttc7a) are suppressed, while inflammatory response genes are stimulated in the mutants. Histological analysis shows neutrophil infiltration into mutant intestinal epithelium and the clearance of gut microbiota. Yet, gut microorganisms appear dispensable as mutants cultured under germ-free condition have similar intestinal defects. Mechanistically, we show that PIK3C3 deficiency suppresses the formation of PI3P and disrupts the polarized distribution of cell-junction proteins in intestinal epithelial cells. These results not only reveal a role of PIK3C3 in gut homeostasis, but also provide a zebrafish IBD model. Show less
Wnt/β-catenin signaling activity is maintained in homeostasis by an expanding list of molecular determinants. However, the molecular components and the regulatory mechanisms involved in its fine-tunin Show more
Wnt/β-catenin signaling activity is maintained in homeostasis by an expanding list of molecular determinants. However, the molecular components and the regulatory mechanisms involved in its fine-tuning remain to be determined. Here, we identified C9orf140, a tumor-specific protein, as a novel Axin1-interacting protein by tandem-affinity purification and mass spectrometry. We further showed that C9orf140 is a negative regulator of Wnt/β-catenin signaling in cultured cells as well as in zebrafish embryos. It functions upstream of β-catenin, outcompetes PP2A for binding to Axin1, influences the balance between phosphorylation and de-phosphorylation of β-catenin, and ultimately compromises Wnt3A-induced β-catenin accumulation. Interestingly, Wnt-induced C9orf140 expression via β-catenin. We propose that C9orf140 mediates a negative feedback loop of Wnt/β-catenin signaling by interacting with Axin1. Our results advance the current understanding of the exquisite control of Wnt/β-catenin signaling cascade, and provide evidence of the new role of C9orf140. Show less
Screening and identifying the gene mutation of EXT1, EXT2 and EXT3 associated with multiple exostosis (ME) and the expression in tumor tissues. Nine patients with multiple exostosis were collected and Show more
Screening and identifying the gene mutation of EXT1, EXT2 and EXT3 associated with multiple exostosis (ME) and the expression in tumor tissues. Nine patients with multiple exostosis were collected and genomic DNA was extracted. Polymerase chain reaction (PCR) amplification and direct sequencing techniques were used to screen all exons, 5' and 3' ends of the EXT1, EXT2 and EXT3 related causative genes. EXT1, EXT2 and EXT3 gene were screened and quantified by RNA-SEQ and RT-qPCR. The concentration of calcitonin gene-related peptide (CGRP) in peripheral blood of tumor patients and normal controls was detected by ELISA. Between the two patients with ME, the EXT1 gene was found in one patient to have c.79 T>A mutation, which caused the change of p.M27T, the non polar methionine was replaced by the high frequency mutation of polar threonine, and the rest of patients was found the splicing mutation c.1284 + 8 delAT of the heterozygosity of the EXT1 gene. The serum CGRP concentration of ME patients (623 + 49 pg/ml) was significantly higher than that of normal controls (196 + 68 pg/ml), and EXT1 mutation patients were also higher than non mutation patients. Show less
Brandon Podyma, Hui Sun, Eric A Wilson+5 more · 2018 · The Journal of biological chemistry · American Society for Biochemistry and Molecular Biology · added 2026-04-24
CAD (Coronary Artery Disease) is a complex disease that influenced by various environmental and genetic factors. Previous studies have found many single nucleotide polymorphisms (SNPs) associated with Show more
CAD (Coronary Artery Disease) is a complex disease that influenced by various environmental and genetic factors. Previous studies have found many single nucleotide polymorphisms (SNPs) associated with the risk of CAD occurrence. However, the results are inconsistent. In this study, we aim to investigate genetic etiology in Chinese Han population by analysis of 7 SNPs in lipid metabolism pathway that previously has been reported to be associated with CAD. A total of 631 samples were used in this study, including 435 CAD cases and 196 normal healthy controls. SNP genotyping were conducted via multiplex PCR amplifying followed by NGS (next-generation sequencing). Rs662799 in APOA5 (Apolipoprotein A5) gene was associated with CAD in Chinese Han population (Odds-ratio = 1.374, P-value = 0.03). No significant association was observed between the rest of SNPs and CAD. Stratified association analysis revealed rs5882 was associated with CAD in non-hypertension group (Odds-ratio = 1.593, P-value = 0.023). Rs1800588 was associated with CAD in smoking group (Odds-ratio = 1.603, P-value = 0.035). The minor allele of rs662799 was the risk factor of CAD occurrences in Chinese Han population. Show less
The traditional Chinese medicine (TCM) Yuanshi Shengmai Chenggu Tablet is used for treating the common orthopedic disease, hormone‑induced avascular necrosis of the femoral head (ANFH) in China. Howev Show more
The traditional Chinese medicine (TCM) Yuanshi Shengmai Chenggu Tablet is used for treating the common orthopedic disease, hormone‑induced avascular necrosis of the femoral head (ANFH) in China. However, its underlying mechanism and the changes induced in the treatment of ANFH remain to be fully elucidated. In the present study, through the use of isobaric Tag for Relative and Absolute Quantitation and multiple reaction monitoring quantifications, corticosteroid‑induced femoral head necrosis and the effects of treatment with Yuanshi Shengmai Chenggu Tablet were examined. The aim was to identify serum proteins, which may be potential serum markers for the early clinical diagnosis of ANFH, and maybe used to develop more rapid and convenient detection strategies. A total of five proteins were identified, comprising Ig mu chain C region, keratin, type I cytoskeletal 9, properdin, apolipoprotein A‑IV, and IQ and AAA domain‑containing protein 1. The expression levels of all five proteins were lower in ANFH and were higher following TCM treatment. These findings were confirmed using ELISA and western blot analysis. Show less
Mechanical unloading was considered a major threat to bone homeostasis, and has been shown to decrease osteoblast proliferation although the underlying mechanism is unclear. Microtubule actin crosslin Show more
Mechanical unloading was considered a major threat to bone homeostasis, and has been shown to decrease osteoblast proliferation although the underlying mechanism is unclear. Microtubule actin crosslinking factor 1 (MACF1) is a cytoskeletal protein that regulates cellular processes and Wnt/β-catenin pathway, an essential signaling pathway for osteoblasts. However, the relationship between MACF1 expression and mechanical unloading, and the function and the associated mechanisms of MACF1 in regulating osteoblast proliferation are unclear. This study investigated effects of mechanical unloading on MACF1 expression levels in cultured MC3T3-E1 osteoblastic cells and in femurs of mice with hind limb unloading; and it also examined the role and potential action mechanisms of MACF1 in osteoblast proliferation in MACF1-knockdown, overexpressed or control MC3T3-E1 cells treated with or without the mechanical unloading condition. Results showed that the mechanical unloading condition inhibited osteoblast proliferation and MACF1 expression in MC3T3-E1 osteoblastic cells and mouse femurs. MACF1 knockdown decreased osteoblast proliferation, while MACF1 overexpression increased it. The inhibitory effect of mechanical unloading on osteoblast proliferation also changed with MACF1 expression levels. Furthermore, MACF1 was found to enhance β-catenin expression and activity, and mechanical unloading decreased β-catenin expression through MACF1. Moreover, β-catenin was found an important regulator of osteoblast proliferation, as its preservation by treatment with its agonist lithium attenuated the inhibitory effects of MACF1-knockdown or mechanical unloading on osteoblast proliferation. Taken together, mechanical unloading decreases MACF1 expression, and MACF1 up-regulates osteoblast proliferation through enhancing β-catenin signaling. This study has thus provided a mechanism for mechanical unloading-induced inhibited osteoblast proliferation. Show less
Blood lipids are well-known risk factors for coronary heart disease (CHD). The aim of this study was to explore the association between 17 lipid-related gene polymorphisms and CHD. The current study e Show more
Blood lipids are well-known risk factors for coronary heart disease (CHD). The aim of this study was to explore the association between 17 lipid-related gene polymorphisms and CHD. The current study examined with 784 CHD cases and 739 non-CHD controls. Genotyping was performed on the MassARRAY iPLEX® assay platform. Our analyses revealed a significant association of APOE rs7259620 with CHD (genotype: χ2=6.353, df=2, p=0.042; allele: χ2=5.05, df=1, p=0.025; recessive model: χ2=5.57, df=1, p=0.018). A further gender-based subgroup analysis revealed significant associations of APOE rs7259620 and PPAP2B rs72664392 with CHD in males (genotype: χ2=8.379, df=2, p=0.015; allele: χ2=5.190, df=1, p=0.023; recessive model: χ2=19.3, df=1, p<0.0001) and females (genotype: χ2=9.878, df=2, p=0.007), respectively. Subsequent breakdown analysis by age showed that CETP rs4783961, MLXIPL rs35493868, and PON2 rs12704796 were significantly associated with CHD among individuals younger than 55 years of age (CETP rs4783961: χ2=8.966, df=1, p=0.011 by genotype; MLXIPL rs35493868: χ2=4.87, df=1, p=0.027 by allele; χ2=4.88, df=1, p=0.027 by dominant model; PON2 rs12704796: χ2=6.511, df=2, p=0.039 by genotype; χ2=6.210, df=1, p=0.013 by allele; χ2=5.03, df=1, p=0.025 by dominant model). Significant allelic association was observed between LEPR rs656451 and CHD among individuals older than 65 years of age (χ2=4.410, df=1, p=0.036). Our study revealed significant associations of APOE, PPAP2B, CETP, MLXIPL, PON2, and LEPR gene polymorphisms with CHD among the Han Chinese. Show less