Leveraging the conserved cancer genomes across mammals has the potential to transform driver gene discovery in orphan cancers. Here, we combine cross-species genomics with validation across human-dog- Show more
Leveraging the conserved cancer genomes across mammals has the potential to transform driver gene discovery in orphan cancers. Here, we combine cross-species genomics with validation across human-dog-mouse systems to uncover a new bone tumor suppressor gene. Comparative genomics of spontaneous human and dog osteosarcomas (OS) expose Disks Large Homolog 2 (DLG2) as a tumor suppressor candidate. DLG2 copy number loss occurs in 42% of human and 56% of canine OS. Functional validation through pertinent human and canine OS DLG2-deficient cell lines identifies a regulatory role of DLG2 in cell division, migration and tumorigenesis. Moreover, osteoblast-specific deletion of Dlg2 in a clinically relevant genetically engineered mouse model leads to acceleration of OS development, establishing DLG2 as a critical determinant of OS. This widely applicable cross-species approach serves as a platform to expedite the search of cancer drivers in rare human malignancies, offering new targets for cancer therapy. Show less
Heat stress has a severe effect on animal health and can reduce the productivity and reproductive efficiency; it is therefore necessary to explore the molecular mechanism involved in heat stress respo Show more
Heat stress has a severe effect on animal health and can reduce the productivity and reproductive efficiency; it is therefore necessary to explore the molecular mechanism involved in heat stress response, which is helpful for the cultivation of an animal breed with resistance to heat stress. However, little research about heat stress-responsive molecular analysis has been reported in sheep. Therefore, in this study, RNA sequencing (RNA-Seq) was used to investigate the transcriptome profiling in the liver of Hu sheep with and without heat stress. In total, we detected 520 and 22 differentially expressed mRNAs and lncRNAs, respectively. The differentially expressed mRNAs were mainly associated with metabolic processes, the regulation of biosynthetic processes, and the regulation of glucocorticoid; additionally, they were significantly enriched in the heat stress related pathways, including the carbon metabolism, the PPAR signaling pathway, and vitamin digestion and absorption. The co-located differentially expressed lncRNA Lnc₀₀₁₇₈₂ might positively influence the expression of the corresponding genes APOA4 and APOA5, exerting co-regulative effects on the liver function. Thus, we made the hypothesis that Lnc₀₀₁₇₈₂, APOA4 and APOA5 might function synergistically to regulate the anti-heat stress ability in Hu sheep. This study provides a catalog of Hu sheep liver mRNAs and lncRNAs, and will contribute to a better understanding of the molecular mechanism underlying heat stress responses. Show less
Micro-RNAs regulate multiple biological behaviors of cancers, making them potential targets of new cancer therapies. MiR-1181 has been demonstrated to perform oncogenic or tumor-suppressing function i Show more
Micro-RNAs regulate multiple biological behaviors of cancers, making them potential targets of new cancer therapies. MiR-1181 has been demonstrated to perform oncogenic or tumor-suppressing function in a tissue-dependent way, but its role in hepatocellular carcinoma (HCC) was unclear. Here, we showed that miR-1181 was significantly overexpressed in HCC tissues when compared with tumor-adjacent normal ones or normal liver tissues from donated organ, and that inhibition of miR-1181 could repress the growth of HCC cells. Through bioinformatics analysis and luciferase reporter assays, we found that axis inhibition protein 1 (AXIN1) was a direct target of miR-1181, and the expression of AXIN1 showed a negative correlation with that of miR-1181 in HCC. Therefore, these data indicated an oncogenic function of miRNA-1181 in the development of HCC and a potential target for the clinical treatment of HCC. Show less
High fructose feeding changes fibroblast growth factor 21 (FGF21) regulation. Lactobacillus rhamnosus GG (LGG) supplementation reduces fructose-induced non-alcoholic fatty liver disease (NAFLD). The a Show more
High fructose feeding changes fibroblast growth factor 21 (FGF21) regulation. Lactobacillus rhamnosus GG (LGG) supplementation reduces fructose-induced non-alcoholic fatty liver disease (NAFLD). The aim of this study was to determine the role of FGF21 and underlying mechanisms in the protective effects of LGG. FGF21 knockout (KO) mice and C57BL/6 wild type (WT) mice were fed 30% fructose for 12 weeks. LGG was administered to the mice in the last 4 weeks during fructose feeding. FGF21-adiponectin (ADPN)-mediated hepatic lipogenesis and inflammation were investigated. FGF21 expression was robustly increased after 5-weeks of feeding and significantly decreased after 12-weeks of feeding in fructose-induced NAFLD mice. LGG administration reversed the depressed FGF21 expression, increased adipose production of ADPN, and reduced hepatic fat accumulation and inflammation in the WT mice but not in the KO mice. Hepatic nuclear carbohydrate responsive-element binding protein (ChREBP) was increased by fructose and reduced by LGG, resulting in a reduction in the expression of lipogenic genes. The methylated form of protein phosphatase 2A (PP2A) C, which dephosphorylates and activates ChREBP, was upregulated by fructose and normalized by LGG. Leucine carboxyl methyltransferase-1, which methylates PP2AC, was also increased by fructose and decreased by LGG. However, those beneficial effects of LGG were blunted in the KO mice. Hepatic dihydrosphingosine-1-phosphate, which inhibits PP2A, was markedly increased by LGG in the WT mice but attenuated in the KO mice. LGG decreased adipose hypertrophy and increased serum levels of ADPN, which regulates sphingosine metabolism. This beneficial effect was decreased in the KO mice. LGG administration increases hepatic FGF21 expression and serum ADPN concentration, resulting in a reduced ChREBP activation through dihydrosphingosine-1-phosphate-mediated PP2A deactivation, and subsequently reversed fructose-induced NAFLD. Thus, our data suggest that FGF21 is required for the beneficial effects of LGG in reversal of fructose-induced NAFLD. Show less
17β-hydroxysteroid dehydrogenase type 3 (17βHSD3) deficiency is an autosomal recessive disorder of male sex development that results in defective testosterone biosynthesis. Although mutations in the c Show more
17β-hydroxysteroid dehydrogenase type 3 (17βHSD3) deficiency is an autosomal recessive disorder of male sex development that results in defective testosterone biosynthesis. Although mutations in the cognate HSD17B3 gene cause a spectrum of phenotypic manifestations, the majority of affected patients are genetic males having female external genitalia. Many cases do not present until puberty, at which time peripheral conversion of androgen precursors causes progressive virilization. Measurement of the testosterone-to-androstenedione ratio is useful to screen for 17βHSD3 deficiency, and genetic analysis can confirm the diagnosis. As some individuals with 17βHSD3 deficiency transition from a female sex assignment to identifying as males, providers should ensure stable gender identity prior to recommending irreversible treatments. Gonadectomy is indicated to prevent further virilization if a female gender identity is established. The risk of testicular neoplasia is unknown, a point which should be discussed if patients elect to transition into a male gender role. Show less
Family with sequence similarity 83, member A (FAM83A), as a potential tumor promoter, was reported to contribute to the progression of several malignant tumors. However, the significance of FAM83A in Show more
Family with sequence similarity 83, member A (FAM83A), as a potential tumor promoter, was reported to contribute to the progression of several malignant tumors. However, the significance of FAM83A in invasion and metastasis of non-small cell lung cancer (NSCLC) remains largely unknown. In this study, we found that FAM83A expression was significantly increased in NSCLC tissues. High expression of FAM83A was positively associated with tumor metastasis and poor survival of NSCLC patients. Functional experiments revealed that FAM83A knockdown could suppress NSCLC cell migration and invasion both Show less
Fusion genes are major molecular biological abnormalities in hematological malignancies. This study aimed to depict the common recurrent gene-fusion landscape in acute myeloid leukemia (AML). 3135 de Show more
Fusion genes are major molecular biological abnormalities in hematological malignancies. This study aimed to depict the common recurrent gene-fusion landscape in acute myeloid leukemia (AML). 3135 de novo AML cases were enrolled and 36 recurrent fusion genes were assessed using multiplex-nested RT-PCR. Twenty-three distinct fusion genes were detected in 1292 (41.21%) cases. The incidence of fusion genes was higher in pediatric AML than in adult cases. The pediatric patients had higher incidences of RUNX1-RUNX1T1, KMT2A-MLLT3, KMT2A-MLLT10, KMT2A-MLLT11, KMT2A-MLLT6, and FUS-ERG, whereas KMT2A-PTD was more common in adult patients. The occurrence of molecular abnormalities involving the KMT2A gene and CBFB-MYH11 was lower in Chinese pediatric AML compared to Western reports. The incidence of RUNX1-RUNX1T1 was higher in both pediatric and adult patients in our study than in Western countries. This study provides a genetic landscape of common fusion genes in Chinese AML and confirms different incidences between age groups and races. Show less
Various cancer stem cell (CSC) biomarkers have been identified for hepatocellular carcinoma (HCC), but little is known about the implications of heterogeneity and shared molecular networks within the Show more
Various cancer stem cell (CSC) biomarkers have been identified for hepatocellular carcinoma (HCC), but little is known about the implications of heterogeneity and shared molecular networks within the CSC population. Through miRNA profile analysis in an HCC cohort ( Show less
EMT allows a polarized epithelium to lose epithelial integrity and acquire mesenchymal characteristics. Previously, we found that overexpression of the intracellular domain of Notch3 (N3ICD) can inhib Show more
EMT allows a polarized epithelium to lose epithelial integrity and acquire mesenchymal characteristics. Previously, we found that overexpression of the intracellular domain of Notch3 (N3ICD) can inhibit EMT in breast cancer cells. In this study, we aimed to elucidate the influence of N3ICD or N3ICD combined with the transmembrane domain (TD+N3ICD) on the expression and distribution of TJs/AJs and polar molecules. We found that although N3ICD can upregulate the expression levels of the above-mentioned molecules, TD+N3ICD can inhibit EMT more effectively than N3ICD alone. TD+N3ICD overexpression upregulated the expression of endogenous full-length Notch3 and contributed to correcting the position of TJs/AJs molecules and better acinar structures formation. Co-immunoprecipitation results showed that the upregulated endogenous full-length Notch3 could physically interact with E-ca in MDA-MB-231/pCMV-(TD+N3ICD) cells. Collectively, our data indicate that overexpression of TD+N3ICD can effectively inhibit EMT, resulting in better positioning of TJs/AJs molecules and cell-cell adhesion in breast cancer cells. Show less
HECT E3 ligases control the degradation and functioning of numerous oncogenic/tumor-suppressive factors and signaling proteins, and their activities must be tightly regulated to prevent cancers and ot Show more
HECT E3 ligases control the degradation and functioning of numerous oncogenic/tumor-suppressive factors and signaling proteins, and their activities must be tightly regulated to prevent cancers and other diseases. Here we show that the Nedd4 family HECT E3 WWP1 adopts an autoinhibited state, in which its multiple WW domains sequester HECT using a multi-lock mechanism. Removing WW2 or WW34 led to a partial activation of WWP1. The structure of fully inhibited WWP1 reveals that many WWP1 mutations identified in cancer patients result in a partially active state with increased E3 ligase activity, and the WWP1 mutants likely promote cell migration by enhancement of ∆Np63α degradation. We further demonstrate that WWP2 and Itch utilize a highly similar multi-lock autoinhibition mechanism as that utilized by WWP1, whereas Nedd4/4 L and Smurf2 utilize a slightly variant version. Overall, these results reveal versatile autoinhibitory mechanisms that fine-tune the ligase activities of the HECT family enzymes. Show less
Intervertebral disc degeneration (IVDD)-related disorders are the major causes of low back pain. A previous study suggested that Notch activation serves as a protective mechanism and is a part of the Show more
Intervertebral disc degeneration (IVDD)-related disorders are the major causes of low back pain. A previous study suggested that Notch activation serves as a protective mechanism and is a part of the compensatory response that maintains the necessary resident nucleus pulposus (NP) cell proliferation to replace lost or non-functional cells. However, the exact mechanism remains to be determined. In this study, we aimed to investigate the role of JAG2/Notch2 in NP cell proliferation and apoptosis. Recombinant JAG2 or Notch2, Hes1, and Hey2 siRNAs were used to activate or inhibit Notch signaling. Cell proliferation, apoptosis, cell cycle regulatory factors, and pathways associated with Notch-mediated proliferation were examined. In vivo experiments involving an intradiscal injection of Sprague-Dawley rats were performed. Recombinant JAG2 induced Notch2 and Hes1/Hey2 expression together with NP cell proliferation. Downregulation of Notch2/Hes1/Hey2 induced G0/G1 phase cell cycle arrest in NP cells. Moreover, Notch2 mediated NP cell proliferation by regulating cyclin D1 and by activating PI3K/Akt and Wnt/β-catenin signaling. Furthermore, Notch signaling inhibited TNF-α-promoted NP cell apoptosis by suppressing the formation of the RIP1-FADD-caspase-8 complex. Finally, we found that intradiscal injection of JAG2 alleviated IVDD and that sh-Notch2 aggravated IVDD in a rat model. These results indicated that JAG2/Notch2 inhibited IVDD by modulating cell proliferation, apoptosis, and extracellular matrix. The JAG2/Notch2 axis regulated NP cell proliferation via PI3K/Akt and Wnt/β-catenin signaling and inhibited TNF-α-induced apoptosis by suppressing the formation of the RIP1-FADD-caspase-8 complex. The current and previous results shed light on the therapeutic implications of targeting the JAG2/Notch2 axis to inhibit or reverse IVDD. Show less
Ying Bai, Ning Liu, Shuang Hu+2 more · 2019 · Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics · added 2026-04-24
To detect EXT1 and EXT2 gene mutations in two pedigrees affected with hereditary multiple exostosis (HME). The coding regions and exon/intron boundaries of the EXT1 and EXT2 genes were analyzed by tar Show more
To detect EXT1 and EXT2 gene mutations in two pedigrees affected with hereditary multiple exostosis (HME). The coding regions and exon/intron boundaries of the EXT1 and EXT2 genes were analyzed by targeted next-generation sequencing (NGS). Suspected mutations were confirmed by Sanger sequencing of the probands, their family members and 200 unrelated healthy controls. Gross deletion was confirmed by quantitative PCR (qPCR) analysis and multiple ligation-dependent probe amplification (MLPA) analysis. Two mutations were detected in the pedigrees, which included EXT2 gene c.337₃₃₈insG mutation in pedigree 1 and deletion of entire EXT1 in pedigree 2. Analysis of sequencing data revealed that a novel heterozygous mutation (c.337₃₃₈insG) in EXT2 gene in proband 1 and his father. The same mutation was not found among healthy family members and 200 unrelated healthy controls. As shown by NGS and MLPA analysis, proband 2 carried a heterozygous deletion of entire EXT1 gene. The same deletion was also found in her mother by qPCR. Mutations of the EXT1 and EXT2 genes probably underlie the HME in both pedigrees. NGS combined with Sanger sequencing, qPCR and MLPA is effective for attaining the diagnosis. Show less
no PDFDOI: 10.3760/cma.j.issn.1003-9406.2019.05.009
Trauma is a leading cause of morbidity and mortality. It is unclear why some trauma victims follow a complicated clinical course and die, while others, with apparently similar injury characteristics, Show more
Trauma is a leading cause of morbidity and mortality. It is unclear why some trauma victims follow a complicated clinical course and die, while others, with apparently similar injury characteristics, do not. Interpatient genomic differences, in the form of single nucleotide polymorphisms (SNPs), have been associated previously with adverse outcomes after trauma. Recently, we identified seven novel SNPs associated with mortality following trauma. The aim of the present study was to determine if one or more of these SNPs was also associated with worse clinical outcomes and altered inflammatory trajectories in trauma survivors. Accordingly, of 413 trauma survivors, DNA samples, full blood samples, and clinical data were collected at multiple time points in the first 24 h and then daily over 7 days following hospital admission. Subsequently, single-SNP groups were created and outcomes, such as hospital length of stay (LOS), ICU LOS, and requirement for mechanical ventilation, were compared. Across a broad range of Injury Severity Scores (ISS), patients carrying the rs2065418 TT SNP in the metallophosphoesterase domain-containing 2 ( Show less
Aberrant activation of Wnt/β-catenin signaling plays a key role in the onset and development of hepatocellular carcinomas (HCC), with about half of them acquiring mutations in either
Antler growth is a unique event compared to other growth and development processes in mammals. Antlers grow extremely fast during the rapid growth stage when growth rate peaks at 2 cm per day. Antler Show more
Antler growth is a unique event compared to other growth and development processes in mammals. Antlers grow extremely fast during the rapid growth stage when growth rate peaks at 2 cm per day. Antler growth is driven by a specific endochondral ossification process in the growth center that is in the distal region of the antler tip. In this study, we used state-of-art RNA-seq technology to analyze the expression profiles of mRNAs and miRNAs during antler growth. Our results indicated that the expression levels of multiple genes involved in chondrogenesis and endochondral ossification, including Show less
Caveolin-1 has been reported to play an important role in the pathogenesis of acute respiratory distress syndrome (ARDS). This study was designed to identify Caveolin-1-interacting proteins to reveal Show more
Caveolin-1 has been reported to play an important role in the pathogenesis of acute respiratory distress syndrome (ARDS). This study was designed to identify Caveolin-1-interacting proteins to reveal the molecular mechanisms of ARDS. Yeast two-hybrid screening was performed using Caveolin-1 as the bait, and Axin-1 was identified as a binding partner for Caveolin-1. Co-immunoprecipitation demonstrated that the binding domains were located in the N-terminal region (1-100 aa) of Caveolin-1 and the C-terminal region (710-797 aa) of Axin-1. Caveolin-1 gene knockout or Axin-1 knockdown significantly decreased the levels of TNF-α and IL-6 in the supernatants of alveolar type I (AT-I) epithelial cells treated with LPS. Disrupting the interaction between Caveolin-1 and Axin-1 using CRISPR/Cas9 technology led to a significant increase in TNF-α and IL-6 from AT-I cells, along with a significant reduction in β-catenin expression. In conclusion, Axin-1 functions as an adaptor of Caveolin-1 and affects the production of inflammatory cytokines in AT-I cells challenged with LPS via β-catenin-mediated negative regulation. Show less
HDL-bound ApoM and albumin are protein chaperones for the circulating bioactive lipid, sphingosine 1-phosphate (S1P); in this role, they support essential extracellular S1P signaling functions in the Show more
HDL-bound ApoM and albumin are protein chaperones for the circulating bioactive lipid, sphingosine 1-phosphate (S1P); in this role, they support essential extracellular S1P signaling functions in the vascular and immune systems. We previously showed that ApoM- and albumin-bound S1P exhibit differences in receptor activation and biological functions. Whether the physiological functions of S1P require chaperones is not clear. We examined ApoM-deficient, albumin-deficient, and double-KO (DKO) mice for circulatory S1P and its biological functions. In albumin-deficient mice, ApoM was upregulated, thus enabling S1P functions in embryonic development and postnatal adult life. The Show less
Hepatic fatty acid oxidation of yolk lipoproteins provides the main energy source for chick embryos. Post-hatching these yolk lipids are rapidly exhausted and metabolism switches to a carbohydrate-bas Show more
Hepatic fatty acid oxidation of yolk lipoproteins provides the main energy source for chick embryos. Post-hatching these yolk lipids are rapidly exhausted and metabolism switches to a carbohydrate-based energy source. We recently demonstrated that many microRNAs (miRNAs) are key regulators of hepatic metabolic pathways during this metabolic switching. MiRNAs are small non-coding RNAs that post-transcriptionally regulate gene expression in most eukaryotes. To further elucidate the roles of miRNAs in the metabolic switch, we used delayed feeding for 48 h to impede the hepatic metabolic switch. We found that hepatic expression of several miRNAs including Show less
Jinpeng Liu, Thilakam Murali, Tianxin Yu+19 more · 2019 · Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology · added 2026-04-24
Lung cancer is the leading cause of cancer mortality in the United States (U.S.). Squamous cell carcinoma (SQCC) represents 22.6% of all lung cancers nationally, and 26.4% in Appalachian Kentucky (App Show more
Lung cancer is the leading cause of cancer mortality in the United States (U.S.). Squamous cell carcinoma (SQCC) represents 22.6% of all lung cancers nationally, and 26.4% in Appalachian Kentucky (AppKY), where death from lung cancer is exceptionally high. The Cancer Genome Atlas (TCGA) characterized genetic alterations in lung SQCC, but this cohort did not focus on AppKY residents. Whole-exome sequencing was performed on tumor and normal DNA samples from 51 lung SQCC subjects from AppKY. Somatic genomic alterations were compared between the AppKY and TCGA SQCC cohorts. From this AppKY cohort, we identified an average of 237 nonsilent mutations per patient and, in comparison with TCGA, we found that This study has identified an increased percentage of Our study is the first report to characterize genomic alterations in lung SQCC from AppKY. These findings suggest population differences in the genetics of lung SQCC between AppKY and U.S. populations, highlighting the importance of the relevant population when developing personalized treatment approaches for this disease. Show less
Long noncoding RNA CPS1-IT1 is recently recognized as a tumor suppressor in several cancers. Here, we investigate the role of CPS1-IT1 in human melanoma. Presently, our study reveals the low expressio Show more
Long noncoding RNA CPS1-IT1 is recently recognized as a tumor suppressor in several cancers. Here, we investigate the role of CPS1-IT1 in human melanoma. Presently, our study reveals the low expression of CPS1-IT1 in human melanoma tissues and cell lines, which is significantly associated with metastasis and tumor stage. Besides, the potential of CPS1-IT1 as a prognosis-predictor is strongly indicated. Functionally, CPS1-IT1 overexpression inhibits cell migration, invasion, epithelial-mesenchymal transition, and angiogenesis in melanoma cells. CYR61, an angiogenic factor that participates in tumor metastasis as well as a recognized oncogene in melanoma, is shown to be confined under CPS1-IT1 overexpression in melanoma cells. Furthermore, enforced expression of Cyr61 in CPS1-IT1-silenced melanoma cells dramatically normalized the protein level of Cyr61 and that of its downstream targets vascular endothelial growth factor and matrix metalloproteinase-9, as well as the repressive effect of CPS1-IT1 overexpression on melanoma cell metastasis. BRG1, a core component of SWI/SNF complex, is implied to interact with both CPS1-IT1 and Cyr61 in melanoma cells. Moreover, CPS1-IT1 negatively regulates Cyr61 expression by blocking the binding of BRG1 to Cyr61 promoter. Jointly, CPS1-IT1 controls melanoma metastasis through impairing Cyr61 expression via competitively binding with BRG1, uncovering a novel potential therapeutic and prognostic biomarker for patients with melanoma. Show less
Tissues rely on stem cells (SCs) for homeostasis and wound repair. SCs reside in specialized microenvironments (niches) whose complexities and roles in orchestrating tissue growth are still unfolding. Show more
Tissues rely on stem cells (SCs) for homeostasis and wound repair. SCs reside in specialized microenvironments (niches) whose complexities and roles in orchestrating tissue growth are still unfolding. Here, we identify lymphatic capillaries as critical SC-niche components. In skin, lymphatics form intimate networks around hair follicle (HF) SCs. When HFs regenerate, lymphatic-SC connections become dynamic. Using a mouse model, we unravel a secretome switch in SCs that controls lymphatic behavior. Resting SCs express angiopoietin-like protein 7 ( Show less
Exosomes, vehicles for intercellular communication, are formed intracellularly within multivesicular bodies (MVBs) and are released upon fusion with the plasma membrane. For their biogenesis, proper c Show more
Exosomes, vehicles for intercellular communication, are formed intracellularly within multivesicular bodies (MVBs) and are released upon fusion with the plasma membrane. For their biogenesis, proper cargo loading to exosomes and vesicle traffic for extracellular release are required. Previously we showed that the L-type lectin, LMAN2, limits trans-Golgi Network (TGN)-to-endosomes traffic of GPRC5B, an exosome cargo protein, for exosome release. Here, we identified that the protein deacetylase sirtuin 2 (SIRT2) as a novel interactor of LMAN2. Loss of SIRT2 expression resulted in exosomal release of LMAN2, a Golgi resident protein, along with increased exosomal release of GPRC5B. Furthermore, knockout of SIRT2 increased total number of extracellular vesicles (EVs), indicating increased MVB-to-EV flux. While knockout of SIRT1 increased EV release with enlarged late endolysosome, knockout of SIRT2 did not exhibit endolysosome enlargement for increased EV release. Taken together, our study suggests that SIRT2 regulates cargo loading to MVBs and MVB-to-EV flux through a mechanism distinct from that of SIRT1. Show less
Fructose has become a major constituent of our modern diet and is implicated as an underlying cause in the development of metabolic diseases. The fructose transporter GLUT5 (SLC2A5) is required for in Show more
Fructose has become a major constituent of our modern diet and is implicated as an underlying cause in the development of metabolic diseases. The fructose transporter GLUT5 (SLC2A5) is required for intestinal fructose absorption. GLUT5 expression is induced in the intestine and skeletal muscle of type 2 diabetes (T2D) patients and in certain cancers that are dependent on fructose metabolism, indicating that modulation of GLUT5 levels could have potential in the treatment of these diseases. Using an unbiased screen for transcriptional control of the human GLUT5 promoter we identified a strong and specific regulation by liver X receptor α (LXRα, NR1H3). Using promoter truncations and site-directed mutagenesis we identified a functional LXR response element (LXRE) in the human GLUT5 promoter, located at -385 bp relative to the transcriptional start site (TSS). Finally, mice treated with LXR agonist T0901317 showed an increase in Glut5 mRNA and protein levels in duodenum and adipose tissue, underscoring the in vivo relevance of its regulation by LXR. Together, our findings show that LXRα regulates GLUT5 in mice and humans. As a ligand-activated transcription factor, LXRα might provide novel pharmacologic strategies for the selective modulation of GLUT5 activity in the treatment of metabolic disease as well as cancer. Show less
High resting heart rate (RHR) occurs in parallel with type 2 diabetes (T2D) and metabolic disorders, implying shared etiology between them. However, it is unknown if they are causally related, and no Show more
High resting heart rate (RHR) occurs in parallel with type 2 diabetes (T2D) and metabolic disorders, implying shared etiology between them. However, it is unknown if they are causally related, and no study has been conducted to investigate the shared mechanisms underlying these associations. The objective of this study was to understand the genetic basis of the association between resting heart rate and cardiometabolic disorders/T2D. This study examined the genetic correlation, causality, and shared genetics between RHR and T2D using LD Score regression, generalized summary data-based Mendelian randomization, and transcriptome wide association scan (TWAS) in UK Biobank data (n = 428,250) and summary-level data for T2D (74,124 cases and 824,006 control subjects) and 8 cardiometabolic traits (sample size ranges from 51,750 to 236,231). Significant genetic correlation between RHR and T2D (r These findings provide evidence of significant genetic correlations and causation between RHR and T2D/cardiometabolic traits, advance our understanding of RHR, and provide insight into shared etiology for high RHR and T2D. Show less
As a member of spectraplakin family of cytoskeletal crosslinking proteins, microtubule-actin crosslinking factor 1 (MACF1) controls cytoskeleton network dynamics. Knockout of
Since metabolic process differs between humans and mice, studies were performed in hamsters, which are generally considered to be a more appropriate animal model for studies of obesity-related metabol Show more
Since metabolic process differs between humans and mice, studies were performed in hamsters, which are generally considered to be a more appropriate animal model for studies of obesity-related metabolic disorders. The modulation of gut microbiota, bile acids and the farnesoid X receptor (FXR) axis is correlated with obesity-induced insulin resistance and hepatic steatosis in mice. However, the interactions among the gut microbiota, bile acids and FXR in metabolic disorders remained largely unexplored in hamsters. In the current study, hamsters fed a 60% high-fat diet (HFD) were administered vehicle or an antibiotic cocktail by gavage twice a week for four weeks. Antibiotic treatment alleviated HFD-induced glucose intolerance, hepatic steatosis and inflammation accompanied with decreased hepatic lipogenesis and elevated thermogenesis in subcutaneous white adipose tissue (sWAT). In the livers of antibiotic-treated hamsters, cytochrome P450 family 7 subfamily B member 1 (CYP7B1) in the alternative bile acid synthesis pathway was upregulated, contributing to a more hydrophilic bile acid profile with increased tauro- Show less
Atherosclerosis is characterized by the accumulation of excess cholesterol in plaques. Reverse cholesterol transport (RCT) plays a key role in the removal of cholesterol. In the present study, we exam Show more
Atherosclerosis is characterized by the accumulation of excess cholesterol in plaques. Reverse cholesterol transport (RCT) plays a key role in the removal of cholesterol. In the present study, we examined the effect of thioredoxin-1 (Trx-1) on RCT and explored the underlying mechanism. We found that Trx-1 promoted RCT in vivo, as did T0901317, a known liver X receptor (LXR) ligand. T0901317 also inhibited the development of atherosclerotic plaques but promoted liver steatosis. Furthermore, Trx-1 promoted macrophage cholesterol efflux to apoAI in vitro. Mechanistically, Trx-1 promoted nuclear translocation of LXRα and induced the expression of ATP-binding cassette transporter A1 (ABCA1). Apolipoprotein E knockout (apoE-/-) mice fed an atherogenic diet were daily injected intraperitoneally with saline or Trx-1 (0.33 mg/kg). Trx-1 treatment significantly inhibited the development of atherosclerosis and induced the expression of ABCA1 in macrophages retrieved from apoE-/- mice. Moreover, the liver steatosis was attenuated by Trx-1. Overall, we demonstrated that Trx-1 promotes RCT by upregulating ABCA1 expression through induction of nuclear translocation of LXRα, and protects liver from steatosis. Show less
Complex mechanisms are required to form neuromuscular synapses, direct their subsequent maturation, and maintain the synapse throughout life. Transcriptional and post-translational pathways play impor Show more
Complex mechanisms are required to form neuromuscular synapses, direct their subsequent maturation, and maintain the synapse throughout life. Transcriptional and post-translational pathways play important roles in synaptic differentiation and direct the accumulation of the neurotransmitter receptors, acetylcholine receptors (AChRs), to the postsynaptic membrane, ensuring for reliable synaptic transmission. Rapsyn, an intracellular peripheral membrane protein that binds AChRs, is essential for synaptic differentiation, but how Rapsyn acts is poorly understood. We screened for proteins that coisolate with AChRs in a Rapsyn-dependent manner and show that microtubule actin cross linking factor 1 (MACF1), a scaffolding protein with binding sites for microtubules (MT) and actin, is concentrated at neuromuscular synapses, where it binds Rapsyn and serves as a synaptic organizer for MT-associated proteins, EB1 and MAP1b, and the actin-associated protein, Vinculin. MACF1 plays an important role in maintaining synaptic differentiation and efficient synaptic transmission in mice, and variants in Show less