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1.
Environ Sci Technol ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622030

RESUMO

The tandem application of CO2 electrolysis with syngas fermentation holds promise for achieving heightened production rates and improved product quality. However, the significant impact of syngas composition on mixed culture-based microbial chain elongation remains unclear. Additionally, effective methods for generating syngas with an adjustable composition from acidic CO2 electrolysis are currently lacking. This study successfully demonstrated the production of medium-chain fatty acids from CO2 through tandem acidic electrolysis with syngas fermentation. CO could serve as the sole energy source or as the electron donor (when cofed with acetate) for caproate generation. Furthermore, the results of gas diffusion electrode structure engineering highlighted that the use of carbon black, either alone or in combination with graphite, enabled consistent syngas generation with an adjustable composition from acidic CO2 electrolysis (pH 1). The carbon black layer significantly improved the CO selectivity, increasing from 0% to 43.5% (0.05 M K+) and further to 92.4% (0.5 M K+). This enhancement in performance was attributed to the promotion of K+ accumulation, stabilizing catalytically active sites, rather than creating a localized alkaline environment for CO2-to-CO conversion. This research contributes to the advancement of hybrid technology for sustainable CO2 reduction and chemical production.

2.
Neurologist ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38251449

RESUMO

OBJECTIVE: We mainly explore the predictive value of Barthel Index (BI), SPAN-100, and National Institute of Health stroke scale (NIHSS) scores on clinical prognosis and functional outcomes in thrombolytic patients and compare the differences in the predictive values of the above 3 scales so as to provide an effective basis to evaluate the prognosis of thrombolytic patients. METHODS: Data were collected from 212 patients with the first-onset AIS (acute ischemic stroke). The enrolled patients were treated with recombinant tissue plasminogen activator thrombolytic therapy and were divided into 2 groups according to the modified Rankin Scale (mRS) score at discharge: the prognosis group (mRS≤2 points) and the poor prognosis group (mRS≥3 points). Logistic multivariate analysis was used to analyze the predictors of poor prognosis in patients with thrombolysis. MedCalc software was used to plot receiver operating characteristic (ROC) curves, calculate the area under the ROC curve (AUC), and compare the prediction performance of the 3 scales by the Delong and colleagues' method, and the difference of P<0.05 was statistically significant. RESULTS: Logistic binary regression multivariate analysis suggested that BI was a predictor of poor prognosis for thrombolytic therapy in patients with AIS. The lower the BI score, the poorer the prognosis. The AUC for BI score was 0.862, 95% CI (0.808-0.906), NIHSS score AUC was 0.665, 95% CI (0.597-0.728), and SPAN-100 score AUC was 0.640, 95% CI (0.572-0.705). AUC comparison of 3 scoring ROC curves suggested statistically significant differences between BI and NIHSS (PC=0.0000), BI and SPAN-100 (PC=0.0000); no significant difference was observed between SPAN-100 and NIHSS (PC=1.7997). CONCLUSIONS: Simple BI scores have a high prognostic value for thrombolytic therapy in AIS.

3.
J Adv Res ; 57: 1-13, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37137429

RESUMO

INTRODUCTION: Fine-wool sheep are the most common breed used by the wool industry worldwide. Fine-wool sheep have over a three-fold higher follicle density and a 50% smaller fiber diameter than coarse-wool sheep. OBJECTIVES: This study aims to clarify the underlying genetic basis for the denser and finer wool phenotype in fine-wool breeds. METHOD: Whole-genome sequences of 140 samples, Ovine HD630K SNP array data of 385 samples, including fine, semi-fine, and coarse wool sheep, as well as skin transcriptomes of nine samples were integrated for genomic selection signature analysis. RESULTS: Two loci at keratin 74 (KRT74) and ectodysplasin receptor (EDAR) were revealed. Fine-scale analysis in 250 fine/semi-fine and 198 coarse wool sheep narrowed this association to one C/A missense variant of KRT74 (OAR3:133,486,008, P = 1.02E-67) and one T/C SNP in the regulatory region upstream of EDAR (OAR3:61,927,840, P = 2.50E-43). Cellular over-expression and ovine skin section staining assays confirmed that C-KRT74 activated the KRT74 protein and specifically enlarged cell size at the Huxley's layer of the inner root sheath (P < 0.01). This structure enhancement shapes the growing hair shaft into the finer wool than the wild type. Luciferase assays validated that the C-to-T mutation upregulated EDAR mRNA expression via a newly created SOX2 binding site and potentially led to the formation of more hair placodes. CONCLUSIONS: Two functional mutations driving finer and denser wool production were characterized and offered new targets for genetic breeding during wool sheep selection. This study not only provides a theoretical basis for future selection of fine wool sheep breeds but also contributes to improving the value of wool commodities.


Assuntos
Receptor Edar , Queratinas Tipo II , Mutação de Sentido Incorreto , , Animais , Receptor Edar/genética , Ovinos/genética , Queratinas Tipo II/genética
4.
Biol Trace Elem Res ; 202(4): 1401-1410, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37715918

RESUMO

To investigate the relationship between selenium (Se) based multi-element combined exposure and cognitive function in rural elderly individuals, a cross-sectional study was conducted. The study involved 416 older adults aged 60 and above, residing in four different areas of Enshi county, China, with varying soil Se levels. Inductively coupled plasma mass spectrometry (ICP-MS) was employed to measure the concentrations of Se, copper (Cu), iron (Fe), zinc (Zn), calcium (Ca), magnesium (Mg), cadmium (Cd), arsenic (As), and lead (Pb) in whole blood. Nine standard cognitive tests were applied to assess cognitive function. Analysis of the least absolute shrinkage and selection operator regression (LASSO), covariance (ANCOVA), and generalized linear model (GLM) were utilized to investigate the relationship between element exposure and cognitive function. The results of LASSO revealed that Se, Cu, Fe, Zn, Ca, and Pb were independently identified to be associated with cognition. Both ANCOVA and GLM demonstrated that Se and Ca were correlated with cognitive function. The multi-element model showed higher composite Z scores of 0.32 (95% CI: 0.09 to 0.55) for log-transformed Se (P = 0.007), 0.75 (95% CI: 0.01 to 1.49) for log-transformed Cu (P = 0.048), and a lower score of - 0.67 (95% CI: - 1.26 to - 0.08) for log-transformed Ca (P = 0.025). Furthermore, there was evidence that Se could counteract the negative impact of Ca on cognitive function (P for interaction = 0.031). Our findings suggested that higher levels of Se and Cu were associated with better cognitive function in the elderly and Se can counteract the cognitive damage caused by Ca.


Assuntos
Selênio , Oligoelementos , Humanos , Idoso , Estudos Transversais , Chumbo , Zinco , Cobre , Cognição
5.
Int Immunopharmacol ; 127: 111345, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38086266

RESUMO

Triptolide (TPT) is widely used in the treatment of rheumatoid arthritis (RA). However, its regulatory mechanisms are not fully understood. This study demonstrated that Myeloid-derived suppressor cells (MDSCs) were expanded in both RA patients and arthritic mice. The frequency of MDSCs was correlated with RA disease severity and T helper 17 (Th17) responses. MDSCs from RA patients promoted the polarization of Th17 cells in vitro, which could be substantially attenuated by blocking arginase-1 (Arg-1). TPT inhibited the differentiation of MDSCs, particularly the monocytic MDSCs (M-MDSCs) subsets, as well as the expression of Arg-1 in a dose dependent manner. Alongside, TPT treatment reduced the potential of MDSCs to promote the polarization of IL-17+ T cell in vitro. Consistently, TPT immunotherapy alleviated adjuvant-induced arthritis (AIA) in a mice model, and reduced the frequency of MDSCs, M-MDSCs and IL-17+ T cells simultaneously. The presented data suggest a pathogenic role of MDSCs in RA and may function as a novel and effective therapeutic target for TPT in RA.


Assuntos
Artrite Reumatoide , Diterpenos , Células Supressoras Mieloides , Fenantrenos , Humanos , Animais , Camundongos , Células Supressoras Mieloides/metabolismo , Interleucina-17/metabolismo , Arginase/metabolismo , Artrite Reumatoide/metabolismo , Compostos de Epóxi
6.
Animals (Basel) ; 13(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37893889

RESUMO

Horns are an important breeding trait for sheep. However, no widely recognized viewpoint on the regulatory genes and mechanisms of horns is available, and the genetic basis of the four-horn phenotype (FHP) is unclear. This work conducted a genome-wide association study with 100 sheep genomes from multiple breeds to investigate the genetic basis of the FHP. The results revealed three significant associations (corrected as p < 1.64 × 10-8) of the InDels (CHR2: g.133,742,709delA, g.133,743,215insC, and g.133,743,940delT) for FHP in the intergenic sequence (IGS) between the MTX2 and the LOC105609047 of CHR2. Moreover, 14 significant associations (corrected as p < 1.42 × 10-9) of SNPs with the FHP phenotype were identified in CHR2 and CHR16, including five (e.g., CHR16: g.40,351,378G > A and g.40,352,577G > A) located in the intron of the ADAMTS12 gene, eight (e.g., CHR2: g.133,727,513C > T and g.133,732,145T > G) in the IGS between MTX2 and LOC105609047, and only one (CHR2: g.133,930,761A > G) in the IGS between HOXD1 and MTX2. Obvious divergence was also observed in genotype patterns between the FHP and others (two horns and hornless) in the HOXD1 and ADAMTS12 gene regions. An extremely significant linkage also occurred between Loci I and Loci II within 100 individuals (LD = -156.02186, p < 0.00001). In summary, our study indicated that the genomic sequences from CHR2 and CHR16 contributed to the FHP in sheep, specifically the key candidate genes HOXD1 and ADAMTS12. These results improved our understanding of the Mendelian genetic basis of the FHP in sheep.

7.
Mol Ther Methods Clin Dev ; 31: 101110, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37822719

RESUMO

SARS-CoV-2, the etiological agent behind the coronavirus disease 2019 (COVID-19) pandemic, has continued to mutate and create new variants with increased resistance against the WHO-approved spike-based vaccines. With a significant portion of the worldwide population still unvaccinated and with waning immunity against newly emerging variants, there is a pressing need to develop novel vaccines that provide broader and longer-lasting protection. To generate broader protective immunity against COVID-19, we developed our second-generation vaccinia virus-based COVID-19 vaccine, TOH-VAC-2, encoded with modified versions of the spike (S) and nucleocapsid (N) proteins as well as a unique poly-epitope antigen that contains immunodominant T cell epitopes from seven different SARS-CoV-2 proteins. We show that the poly-epitope antigen restimulates T cells from the PBMCs of individuals formerly infected with SARS-CoV-2. In mice, TOH-VAC-2 vaccination produces high titers of S- and N-specific antibodies and generates robust T cell immunity against S, N, and poly-epitope antigens. The immunity generated from TOH-VAC-2 is also capable of protecting mice from heterologous challenge with recombinant VSV viruses that express the same SARS-CoV-2 antigens. Altogether, these findings demonstrate the effectiveness of our versatile vaccine platform as an alternative or complementary approach to current vaccines.

8.
PeerJ ; 11: e15690, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37525657

RESUMO

Rheumatoid arthritis (RA) is a refractory autoimmune disease, affecting about 1% of the world's population. RA is divided into seronegative RA and seropositive RA. However, biomarkers for discriminating between seronegative and seropositive RA have not been reported. In this study, we profiled serum miRNAs in seronegative RA patients (N-RA), seropositive RA patients (P-RA) and healthy controls (HC) by small RNA sequencing. Results indicated that compared with HC group, there were one up-regulated and four downregulated miRNAs in N-RA group (fold change ≥ 2 and P value < 0.05); compared with P-RA group, there were two up-regulated and four downregulated miRNAs in N-RA group; compared with HC group, there were three up-regulated and four downregulated miRNAs in P-RA group. Among them, the level of hsa-miR-362-5p in N-RA group was up-regulated compared with that in HC group and P-RA group, and the level of hsa-miR-6855-5p and hsa-miR-187-3p in P-RA group was upregulated compared with that in N-RA group and HC group. Validation by qPCR confirmed that serum hsa-miR-362-5p level was elevated in N-RA group. Subsequently, by analyzing the target genes using RNAhybrid, PITA, Miranda and TargetScan and functions of differential miRNAs utilizing Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), we found that the target genes and molecular pathways regulated by miRNAs in seronegative RA and seropositive RA were roughly the same, and miRNAs in these two diseases may participate in the occurrence and development of diseases by regulating the immune system. In conclusion, this study revealed the profiles of serum miRNAs in seronegative and seropositive RA patients for the first time, providing potential biomarkers and targets for the diagnosis and treatment of seronegative and seropositive RA.


Assuntos
Artrite Reumatoide , MicroRNAs , Humanos , MicroRNAs/genética , Artrite Reumatoide/diagnóstico , Sequência de Bases , Análise de Sequência de RNA/métodos , Biomarcadores/metabolismo
9.
J Food Sci ; 88(9): 3879-3892, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37458306

RESUMO

A novel whole peanut butter (PB) was developed using an emerging technology called stirred media mill (SMM). The impact of SMM on the size, microstructure, rheology, nutrient, and flavor of PB was investigated. The SMM treatment significantly decreased the particle size of PB, damaged cell structure, and released the oil body from cells. The apparent viscosity of PB decreased with the grinding process. Visual inspection revealed that the colloidal stability of PB was improved. The fatty acid composition was not affected by the grinding process. However, the tocopherol contents of the extracted oil slightly increased. Electronic nose and GC-MS analysis indicated that SMM could alter the flavor of PB after grinding for 45 min. Overall, SMM was a potential process technology to manufacture stable nut butter with smooth texture and delightful flavor profile.


Assuntos
Arachis , Ácidos Graxos , Arachis/química , Nutrientes , Reologia
10.
Biology (Basel) ; 12(7)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37508473

RESUMO

In the original publication [1], there were mistakes in the order of the references, which were as follows: [...].

11.
Pathol Oncol Res ; 29: 1611055, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168049

RESUMO

Background: The association between pretreatment skeletal muscle index (SMI) and long-term survival of gastric cancer patients remains unclear up to now. The aim of this meta-analysis was to identify the prognostic value of pretreatment SMI in gastric cancer. Methods: The PubMed, EMBASE and Web of Science electronic databases were searched up to 5 June 2022 for relevant studies. The primary outcome was overall survival (OS) and the second outcomes were disease-free survival (DFS) and cancer-specific survival (CSS). The hazard ratios (HRs) and 95% confidence intervals (CIs) were combined to assess the relationship between pretreatment SMI and survival of gastric cancer patients. All statistical analyses were conducted by STATA 15.0 software. Results: A total of 31 retrospective studies involving 12,434 patients were enrolled in this meta-analysis. The pooled results demonstrated that lower pretreatment was significantly associated with poorer OS (HR = 1.53, p < 0.001). Besides, lower pretreatment SMI was also related with worse DFS (HR = 1.39, p < 0.001) and CSS (HR = 1.96, p < 0.001). Conclusion: Pretreatment SMI was significantly associated with prognosis of gastric cancer patients and lower SMI predicted worse survival. However, more prospective high-quality studies are still needed to verify our findings.


Assuntos
Neoplasias Gástricas , Humanos , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Músculo Esquelético
12.
Nat Commun ; 14(1): 3035, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37236967

RESUMO

The large coding potential of vaccinia virus (VV) vectors is a defining feature. However, limited regulatory switches are available to control viral replication as well as timing and dosing of transgene expression in order to facilitate safe and efficacious payload delivery. Herein, we adapt drug-controlled gene switches to enable control of virally encoded transgene expression, including systems controlled by the FDA-approved rapamycin and doxycycline. Using ribosome profiling to characterize viral promoter strength, we rationally design fusions of the operator element of different drug-inducible systems with VV promoters to produce synthetic promoters yielding robust inducible expression with undetectable baseline levels. We also generate chimeric synthetic promoters facilitating additional regulatory layers for VV-encoded synthetic transgene networks. The switches are applied to enable inducible expression of fusogenic proteins, dose-controlled delivery of toxic cytokines, and chemical regulation of VV replication. This toolbox enables the precise modulation of transgene circuitry in VV-vectored oncolytic virus design.


Assuntos
Terapia Viral Oncolítica , Vírus Oncolíticos , Vetores Genéticos/genética , Vírus Vaccinia/genética , Vírus Oncolíticos/genética , Regiões Promotoras Genéticas/genética
13.
Biology (Basel) ; 12(4)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37106791

RESUMO

Horns, also known as headgear, are a unique structure of ruminants. As ruminants are globally distributed, the study of horn formation is critical not only for increasing our understanding of natural and sexual selection but also for the breeding of polled sheep breeds to facilitate modern sheep farming. Despite this, a significant number of the underlying genetic pathways in sheep horn remain unclear. In this study, to clarify the gene expression profile of horn buds and investigate the key genes in horn bud formation, RNA-sequencing (RNA-seq) technology was utilized to investigate differential gene expression in the horn buds and adjacent forehead skin of Altay sheep fetuses. There were only 68 differentially expressed genes (DEGs) identified, consisting of 58 up-regulated genes and 10 down-regulated genes. RXFP2 was differentially up-regulated in the horn buds and had the highest significance (p-value = 7.42 × 10-14). In addition, 32 DEGs were horn-related genes identified in previous studies, such as RXFP2, FOXL2, SFRP4, SFRP2, KRT1, KRT10, WNT7B, and WNT3. Further, Gene Ontology (GO) analysis showed that the DEGs were mainly enriched with regard to growth, development, and cell differentiation. Pathway analysis revealed that the Wnt signaling pathway may be responsible for horn development. Further, through combining the protein-protein interaction networks of the DEGs, it was found that the top five hub genes, namely, ACAN, SFRP2, SFRP4, WNT3, and WNT7B, were also associated with horn development. Our results suggest that only a few key genes, including RXFP2, are involved in bud formation. This study not only validates the expression of candidate genes identified at the transcriptome level in previous studies but also provides new possible marker genes for horn development, which may promote our understanding of the genetic mechanisms of horn formation.

14.
J Biol Chem ; 299(6): 104749, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37100284

RESUMO

The recent SARS-CoV-2 and mpox outbreaks have highlighted the need to expand our arsenal of broad-spectrum antiviral agents for future pandemic preparedness. Host-directed antivirals are an important tool to accomplish this as they typically offer protection against a broader range of viruses than direct-acting antivirals and have a lower susceptibility to viral mutations that cause drug resistance. In this study, we investigate the exchange protein activated by cAMP (EPAC) as a target for broad-spectrum antiviral therapy. We find that the EPAC-selective inhibitor, ESI-09, provides robust protection against a variety of viruses, including SARS-CoV-2 and Vaccinia (VACV)-an orthopox virus from the same family as mpox. We show, using a series of immunofluorescence experiments, that ESI-09 remodels the actin cytoskeleton through Rac1/Cdc42 GTPases and the Arp2/3 complex, impairing internalization of viruses that use clathrin-mediated endocytosis (e.g. VSV) or micropinocytosis (e.g. VACV). Additionally, we find that ESI-09 disrupts syncytia formation and inhibits cell-to-cell transmission of viruses such as measles and VACV. When administered to immune-deficient mice in an intranasal challenge model, ESI-09 protects mice from lethal doses of VACV and prevents formation of pox lesions. Altogether, our finding shows that EPAC antagonists such as ESI-09 are promising candidates for broad-spectrum antiviral therapy that can aid in the fight against ongoing and future viral outbreaks.


Assuntos
Antivirais , COVID-19 , Vaccinia , Animais , Camundongos , Antivirais/farmacologia , SARS-CoV-2/efeitos dos fármacos , Vaccinia/tratamento farmacológico , Vírus Vaccinia/efeitos dos fármacos
15.
Ecotoxicol Environ Saf ; 257: 114914, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37084658

RESUMO

Ingestion of arsenic interferes with spermatogenesis and increases the risk of male infertility, but the underlying mechanism remines unclear. In this study, we investigated spermatogenic injury with a focus on blood-testis barrier (BTB) disruption by administrating 5 mg/L and 15 mg/L arsenic orally to adult male mice for 60 d. Our results showed that arsenic exposure reduced sperm quality, altered testicular architecture, and impaired Sertoli cell junctions at the BTB. Analysis of BTB junctional proteins revealed that arsenic intake downregulated Claudin-11 expression and increased protein levels of ß-catenin, N-cadherin, and Connexin-43. Aberrant localization of these membrane proteins was also observed in arsenic-treated mice. Meanwhile, arsenic exposure altered the components of Rictor/mTORC2 pathway in mouse testis, including inhibition of Rictor expression, reduced phosphorylation of protein kinase Cα (PKCα) and protein kinase B (PKB), and elevated matrix metalloproteinase-9 (MMP-9) levels. Furthermore, arsenic also induced testicular lipid peroxidative damage, inhibited antioxidant enzyme (T-SOD) activity, and caused glutathione (GSH) depletion. Our findings suggest that disruption of BTB integrity is one of the main factors responsible for the decline in sperm quality caused by arsenic. PKCα-mediated rearrangement of actin filaments and PKB/MMP-9-increased barrier permeability jointly contribute to arsenic-induced BTB disruption.


Assuntos
Arsênio , Camundongos , Masculino , Animais , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Arsênio/toxicidade , Arsênio/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteína Quinase C-alfa/metabolismo , Barreira Hematotesticular/metabolismo , Sêmen , Testículo/metabolismo , Espermatogênese , Fatores de Transcrição/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/metabolismo
17.
Animals (Basel) ; 13(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36978617

RESUMO

Skeletal muscle satellite cells (SMSCs), which are highly multifunctional muscle-derived stem cells, play an essential role in myogenesis and regeneration. Here, the transcriptional profile of SMSCs during proliferation and differentiation were constructed using the RNA-Seq method. A total of 1954 differentially expressed genes (DEGs) and 1092 differentially alternative splicing genes (DAGs) were identified including 1288 upregulated genes as well as 666 downregulated genes. GO and KEGG analyses showed that the DEGs and DAGs were enriched in the MAPK (mitogen-activated protein kinase) signaling pathway, the PI3K-Akt (phosphatidylinositol-tris-phosphate kinase 3/protein kinase B) signaling pathway, the Wnt signaling pathway, and the Ras signaling pathway. In total, 1479 alternative splice events (AS) were also identified during SMSC proliferation and differentiation. Among them, a unique AS event was the major per-mRNA splicing type, and SE was the predominant splicing pattern. Furthermore, transcription factors with AS were scanned during SMSC differentiation such as myocyte enhancer factor-2C (MEF2C) and the nuclear receptor subfamily 4 group A member 2 (NR4A2). Our results imply that MEF2C and NR4A2 can interact, and we speculate that NR4A2 and MEF2C might regulate the myogenesis of ovine SMSCs through interaction. Together, our study provides useful information on the transcriptional regulation of SMSCs during proliferation and differentiation at the transcriptional level, and provides a valuable resource for understanding the molecular mechanism of myogenesis and muscle development.

20.
Int J Mol Sci ; 24(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36768334

RESUMO

Triacylglycerol (TG) biosynthesis is an important metabolic process for intracellular storage of surplus energy, intestinal dietary fat absorption, attenuation of lipotoxicity, lipid transportation, lactation and signal transduction in mammals. Transmembrane protein 68 (TMEM68) is an endoplasmic reticulum (ER)-anchored acyltransferase family member of unknown function. In the current study we show that overexpression of TMEM68 promotes TG accumulation and lipid droplet (LD) formation in a conserved active sites-dependent manner. Quantitative targeted lipidomic analysis showed that diacylglycerol (DG), free fatty acid (FFA) and TG levels were increased by TMEM68 expression. In addition, TMEM68 overexpression affected the levels of several glycerophospholipids, such as phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol, as well as sterol ester contents. TMEM68 exhibited monoacylglycerol acyltransferase (MGAT) and diacylglycerol acyltransferase (DGAT) activities dependent on the conserved active sites in an in vitro assay. The expression of lipogenesis genes, including DGATs, fatty acid synthesis-related genes and peroxisome proliferator-activated receptor γ was upregulated in TMEM68-overexpressing cells. These results together demonstrate for the first time that TMEM68 functions as an acyltransferase and affects lipogenic gene expression, glycerolipid metabolism and TG storage in mammalian cells.


Assuntos
Diacilglicerol O-Aciltransferase , Lipogênese , Proteínas de Membrana , Triglicerídeos , Animais , Feminino , Humanos , Aciltransferases/genética , Aciltransferases/metabolismo , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Lipogênese/genética , Lipogênese/fisiologia , Mamíferos/metabolismo , Triglicerídeos/biossíntese , Triglicerídeos/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
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