Distinct expression profiles of transcriptional coactivators for thyroid hormone receptors during Xenopus laevis metamorphosis

The biological effects of thyroid hormone (T3) are mediated by the thyroid hormone receptor (TR). Amphibian metamorphosis is one of the most dramatic processes that are dependent on T3. T3 regulates a series of orchestrated developmental changes, which ultimately result in the conversion of an aquatic herbivorous tadpole to a terrestrial carnivorous frog. T3 is presumed to bind to TRs, which in turn recruit coactivators, leading to gene activation. The best-studied coactivators belong to the p160 or SRC family. Members of this family include SRC1/NCoA-1, SRC2/TIF2/GRIP1, and SRC3/pCIP/ACTR/AIB-1/RAC-3/TRAM-1. These SRCs interact directly with liganded TR and function as adapter molecules to recruit other coactivators such as p300/CBP. Here, we studied the expression patterns of these coactivators during various stages of development. Amongst the coactivators cloned in Xenopus laevis, SRC3 was found to be dramatically upregulated during natural and T3-induced metamorphosis, and SRC2 and p300 are expressed throughout postembryonic development with little change in their expression levels. These results support the view that these coactivators participate in gene regulation by TR during metamorphosis.

Irisin/BDNF signaling in the muscle-brain axis and circadian system: A review

In mammals,the timing of physiological,biochemical and behavioral processes over a 24-h period is controlled by circadian rhythms.To entrain the master clock located in the suprachiasmatic nucleus of the hypothalamus to a precise 24-h rhythm,environmental zeitgebers are used by the circadian system.This is done primarily by signals from the retina via the retinohypothalamic tract,but other cues like exercise,feeding,temperature,anxiety,and social events have also been shown to act as non-photic zeitgebers.The recently identified myokine irisin is proposed to serve as an entraining non-photic signal of exercise.Irisin is a product of cleavage and modification from its precursor membrane fibronectin typeⅢdomain-containing protein 5(FNDC5)in response to exercise.Apart from well-known peripheral effects,such as inducing the"browning"of white adipocytes,irisin can penetrate the blood-brain barrier and display the effects on the brain.Experimental data suggest that FNDC5/irisin mediates the positive effects of physical activity on brain functions.In several brain areas,irisin induces the production of brain-derived neurotrophic factor(BDNF).In the master clock,a significant role in gating photic stimuli in the retinohypothalamic synapse for BDNF is suggested.However,the brain receptor for irisin remains unknown.In the current review,the interactions of physical activity and the irisin/BDNF axis with the circadian system are reconceptualized.

Activation of G-protein-coupled receptor 39 reduces neuropathic pain in a rat model

Activated G-protein-coupled receptor 39(GPR39)has been shown to attenuate inflammation by interacting with sirtuin 1(SIRT1)and peroxisome proliferator-activated receptor-γcoactivator 1α(PGC-1α).However,whether GPR39 attenuates neuropathic pain remains unclear.In this study,we established a Sprague-Dawley rat model of spared nerve injury-induced neuropathic pain and found that GPR39 expression was significantly decreased in neurons and microglia in the spinal dorsal horn compared with sham-operated rats.Intrathecal injection of TC-G 1008,a specific agonist of GPR39,significantly alleviated mechanical allodynia in the rats with spared nerve injury,improved spinal cord mitochondrial biogenesis,and alleviated neuroinflammation.These changes were abolished by GPR39 small interfering RNA(siRNA),Ex-527(SIRT1 inhibitor),and PGC-1αsiRNA.Taken together,these findings show that GPR39 activation ameliorates mechanical allodynia by activating the SIRT1/PGC-1αpathway in rats with spared nerve injury.

Inhibition of autophagy rescues HT22 hippocampal neurons from erastin-induced ferroptosis

Ferroptosis is a regulated form of cell death which is considered an oxidative iron-dependent process.The lipid hydroperoxidase glutathione peroxidase 4 prevents the iron(Fe2+)-dependent formation of toxic lipid reactive oxygen species.While emerging evidence indicates that inhibition of glutathione peroxidase 4 as a hallmark of ferroptosis in many cancer cell lines,the involvement of this biochemical pathway in neuronal death remains largely unclear.Here,we investigate,first whether the ferroptosis key players are involved in the neuronal cell death induced by erastin.The second objective was to examine whether there is a cross talk between ferroptosis and autophagy.The third main was to address neuron response to erastin,with a special focus on ferritin and nuclear receptor coactivator 4-mediated ferritinophagy.To test this in neurons,erastin(0.5-8μM)was applied to hippocampal HT22 neurons for 16 hours.In addition,cells were cultured with the autophagy inhibitor,3-methyladenin(10 mM)and/or ferroptosis inhibitors,ferrostatin 1(10-20μM)or deferoxamine(10-200μM)before exposure to erastin.In this study,we demonstrated by immunofluorescence and western blot analysis,that erastin downregulates dramatically the expression of glutathione peroxidase 4,the sodium-independent cystine-glutamate antiporter and nuclear receptor coactivator 4.The protein levels of ferritin and mitochondrial ferritin in HT22 hippocampal neurons did not remarkably change following erastin treatment.In addition,we demonstrated that not only the ferroptosis inhibitor,ferrostatin1/deferoxamine abrogated the ferroptotic cell death induced by erastin in hippocampal HT22 neurons,but also the potent autophagy inhibitor,3-methyladenin.We conclude that(1)erastin-induced ferroptosis in hippocampal HT22 neurons,despite reduced nuclear receptor coactivator 4 levels,(2)that either nuclear receptor coactivator 4-mediated ferritinophagy does not occur or is of secondary importance in this model,(3)that ferroptosis seems to share some features of the autophagic cell death process.

The X-linked mental retardation gene PHF8 is a histone demethylase involved in neuronal differentiation

Recent studies have identified mutations in PHF8, an X-linked gene encoding a JmjC domain-containing protein, as a causal factor for X-linked mental retardation （XLMR） and cleft lip/cleft palate. However, the underlying mechanism is unknown. Here we show that PHF8 is a histone demethylase and coactivator for retinoic acid receptor （RAR）. Although activities for both H3K4me3/2/1 and H3K9me2/1 demethylation were detected in cellularbased assays, reeombinant PHF8 exhibited only H3K9me2/1 demethylase activity in vitro, suggesting that PHF8 is an H3K9me2/1 demethylase whose specificity may be modulated in vivo. Importantly, a mutant PHF8 （phenylalanine at position 279 to serine） identified in the XLMR patients is defective in enzymatie activity, indicating that the loss of histone demethylase activity is causally linked with the onset of disease. In addition, we show that PHF8 binds specifically to H3K4me3/2 peptides via an N-terminal PHD finger domain. Consistent with a role for PHF8 in neuronal differentiation, knockdown of PHF8 in mouse embryonic carcinoma P19 cells impairs RA-induced neuronal differentiation, whereas overexpression of the wild-type but not the F279S mutant PHF8 drives PI9 cells toward neuronal differentiation. Furthermore, we show that PHF8 interacts with RAR~ and functions as a coactivator for RARa. Taken together, our results suggest that histone methylation modulated by PHF8 plays a critical role in neuronal differentiation.

Micro RNA-124 slows down the progression of Huntington's disease by promoting neurogenesis in the striatum

MicroRNA-124 contributes to neurogenesis through regulating its targets, but its expression both in the brain of Huntington＇s disease mouse models and patients is decreased. However, the effects of microRNA-124 on the progression of Huntington＇s disease have not been reported. Results from this study showed that microRNA-124 increased the latency to fall for each R6/2 Hunting- ton＇s disease transgenic mouse in the rotarod test. 5-Bromo-2＇-deoxyuridine （BrdU） staining of the striatum shows an increase in neurogenesis. In addition, brain-derived neurotrophic factor and peroxisome proliferator-activated receptor gamma coactivator 1-alpha protein levels in the striatum were increased and SRY-related HMG box transcription factor 9 protein level was de- creased. These findings suggest that microRNA-124 slows down the progression of Huntington＇s disease possibly through its important role in neuronal differentiation and survival.

Estrogen Receptor α(ERα) Target Gene LRP16 Interacts with ERα and Enhances Receptor's Transcriptional Activity

Objective：It has been shown that LRP16 is an estrogen-induced gene through its receptor α（ERα）. Although there is evidence demonstrating that inhibition of LRP16 gene expression in MCF-7 human breast cancer cells partially attenuates its estrogen-responsiveness, the underlying molecular mechanism is still unclear. Here, the effect of LRP16 expression on the ERα signaling transduction was investigated. Methods： Cotransfection assays were used to measure the effect of LRP16 on ERα-mediated transcriptional activity. GST-pulldown and immunoprecipitation （ColP） assays were employed to investigate the physical interaction of LRP16 and ERα. The mammalian two-hybrid method was used to map the functional interaction region. Results： the results of cotransfection assays demonstrated that the transcriptional activities of ERα were enhanced in α LRP16 dose-dependent manner in MCF-7 in the presence of estrogen, however, it was abolished in the absence of E2 in MCF-7 cells. The physical interaction of LRP16 and ERα proteins was confirmed by GST-pulldown in vitro and ColP in vivo assays, which was enhanced by E2 but not dependent on its presence. Furthermore, the results of the mammalian two-hybrid assays indicated that the binding region of ERα to LRP16 located at the A/B AF-1 functional domain and E2 stimulated the binding of LRP16 to the full-length ERα molecule but not to the A/B region alone. Conclusion： These results support a role for estrogenically regulated LRP16 as an ERα coactivator, providing a positive feedback regulatory loop for ERα signal transduction. Based on this function of LRP16, we propose that ERα-positive breast cancer patients with high expression of LRP16 might benefit from targeting LRP16 therapy.

The role of mitochondria in redox signaling of muscle homeostasis

In the past,contraction-induced production of reactive oxygen species(ROS)has been implicated in oxidative stress to skeletal muscle.As research advances,clear evidence has revealed a more complete role of ROS under both physiologic and pathologic conditions.Central to the role of ROS is the redox signaling pathways that control exercise-induced major physiologic and cellular responses and adaptations,such as mitochondrial biogenesis,mitophagy,mitochondrial morphologic dynamics,antioxidant defense,and inflammation.The current review focuses on how muscle contraction and immobilization may activate or inhibit redox signalings and their impact on muscle mitochondrial homeostasis and physiologic implications.

The adenoviral E1A protein relieves gene repression by receptors in v/vo displaces corepressors and unliganded thyroid hormone

The human adenovirus type 5 early region 1A （E1A） is one of two oncogenes present in the adenovirus genome and functions by interfering with the activities of cellular regulatory proteins. The E1A gene is alternatively spliced to yield five products. Earlier studies have revealed that E1A can regulate the function of thyroid hormone （T3） receptors （TRs）. However, analysis in yeast compared with transfection studies in mammalian cell cultures yields surprisingly different effects. Here, we have examined the effect of E1A on TR function by using the frog oocyte in vivo system, where the effects of E1A can be studied in the context of chromatin. We demonstrate that different isoforms of E1A have distinct effects on TR function. The two longest forms inhibit both the repression by unliganded TR and activation by T3-bound TR. We further show that E1A binds to unliganded TR to displace the endogenous corepressor nuclear receptor corepressor, thus relieving the repression by unliganded TR. On the other hand, in the presence of T3, E1A inhibits gene activation by T3-bound TR indirectly, through a mechanism that requires its binding domain for the general coactivator p300. Taken together, our results thus indicate that E1A affects TR function through distinct mechanisms that are dependent upon the presence or absence of T3.

Ipragliflozin-induced improvement of liver steatosis in obese mice may involve sirtuin signaling

BACKGROUND Sodium glucose cotransporter 2(SGLT2)inhibitors are newly developed oral antidiabetic drugs.SGLT2 is primarily expressed in the kidneys and reabsorbs approximately 90%of the glucose filtered by the renal glomeruli.SGLT2 inhibitors lower glucose levels independently of insulin action by facilitating urinary glucose excretion.The SGLT2 inhibitor ipragliflozin has reportedly improved liver steatosis in animal models and clinical studies.However,the mechanisms by which SGLT2 inhibitors improve liver steatosis are not fully understood.AIM To investigate the ameliorative effects of ipragliflozin on liver steatosis and the mechanisms of these effects in obese mice.METHODS We analyzed 8-wk-old male obese(ob/ob)mice that were randomly divided into a group receiving a normal chow diet and a group receiving a normal chow diet supplemented with ipragliflozin(3 mg/kg or 10 mg/kg)for 4 wk.We also analyzed their lean sex-matched littermates receiving a normal chow diet as another control group. Body weight and liver weight were evaluated, and liverhistology, immunoblotting, and reverse transcription-polymerase chain reactionanalyses were performed.RESULTSHepatic lipid accumulation was significantly ameliorated in ob/ob mice treatedwith 10 mg/kg ipragliflozin compared to untreated ob/ob mice irrespective ofbody weight changes. Ipragliflozin had no appreciable effects on hepatic oxidativestress-related gene expression levels or macrophage infiltration, but significantlyreduced hepatic interleukin-1β (IL-1β) mRNA expression levels. Ipragliflozinincreased both the mRNA and protein expression levels of sirtuin 1 (SIRT1) in theliver. The hepatic mRNA levels of peroxisome proliferator-activated receptor γcoactivator 1α (PGC-1α), peroxisome proliferator-activated receptor α (PPARα),and fibroblast growth factor-21 (FGF21) were also significantly higher inipragliflozin-treated ob/ob mice than in untreated ob/ob mice.CONCLUSIONOur study suggests that the liver steatosis-ameliorating effects of ipragliflozin inob/ob mice may be mediated partly by hepatic SIRT1 signaling, possibly throughthe PGC-1α/PPARα-FGF21 pathway.

Inhibitory roles of protein kinase B and peroxisome proliferator-activated receptor gamma coactivator on hepatic HMG-CoA reductase promoter activity

Since we had previously demonstrated that siRNAs to tristetraprolin (TTP) markedly inhibited insulin stimulation of hepatic HMG-CoA reductase (HMGR) transcription, we investigated the effects of transfecting rat liver with TTP constructs. We found that transfecting diabetic rats with TTP did not increase HMGR transcription but rather led to modest inhibition. We then investigated whether co-transfection with protein kinase B, hepatic form (AKT2), might lead to phosphorylation and result in activation of HMGR transcription. We found that this treatment resulted in near complete inhibition of transcription. Transfection with peroxisome proliferator-activated receptor g coactivator (PGC-1a) also inhibited HMGR transcription. These results show that although TTP is needed for activation of HMGR transcription, it cannot by itself activate this process. AKT2 and PGC-1a, which mediate the activation of gluconeogenic genes by insulin, exert the opposite effect on HMGR.

CANFIS—a computer aided diagnostic tool for cancer detection

In this investigation, an approach using Coac-tive Neuro-Fuzzy Inference System (CANFIS) as diagnosis system for breast cancer has been proposed on Wisconsin Breast Cancer Data (WBCD). It is occasionally difficult to attain the ultimate diagnosis even for medical experts due to the complexity and non-linearity of the rela-tionships between the large measured factors, which can be possibly resolved with a human like decision-making process using Artificial Intelligence (AI) algorithms. CANFIS is an AI algorithm which has the advantages of both fuzzy inference system and neural networks and can deal with ambiguous data and learn from the past data by itself. The Multi Layer Percep-tron Neural Network (MLPNN), Probabilistic Neural Network (PNN) Principal Component Analysis (PCA), Support Vector Machine (SVM) and Self Organizing Map (SOM) were also tested and benchmarked for their

可改善人体触觉功能的新技术

一份新的研究报告称,德国科学家最近发明了一种新技术,利用这一技术可改善人体的触觉功能,而且用两种不同的药物能加强或者减弱这种作用.研究人员认为,这一发现将会引导我们发明一种治疗老年人、中风患者和其他情况下出现的感觉障碍性疾病的新方法.

Mechanism of acupuncture in attenuating cerebral ischaemia-reperfusion injury based on nuclear receptor coactivator 4 mediated ferritinophagy

OBJECTIVE:To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury(CIRI)and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4(NCOA4)mediated ferritinophagy.METHODS:Sprague-Dawley male rats were divided into four groups:the sham group,model group,acupuncture group,and sham acupuncture group.After 2 h of middle cerebral artery occlusion(MCAO),reperfusion was performed for 24 h to induce CIRI.The rats were treated with acupuncture at the Neiguan(PC6)and Shuigou(GV26)acupoints.Their neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after reperfusion.Triphenyltetrazolium chloride staining was applied to assess the cerebral infarct volume at 24 h after reperfusion.The malondialdehyde(MDA)and ferrous iron(Fe^(2+))levels were observed after 24 h of reperfusion using an assay kit.Western blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1(FTH1)at 24 h after reperfusion.Moreover,the colocalization of ferritin with neurons,NCOA4 with microtubule-associated protein 1 light chain 3(LC3),and NCOA4 with ferritin was visualized using immunofluorescence staining.RESULTS:Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture group.Following CIRI,the expression of NCOA4,LC3 and FTH1 was increased,which enhanced ferritinophagy and induced an inappropriate accumulation of Fe^(2+)and MDA in the ischaemic brain.However,acupuncture dramatically downregulated the expression of NCOA4,LC3 and FTH1,inhibited the overactivation of ferritinophagy,and decreased the levels of MDA and Fe^(2+).CONCLUSIONS:Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.

Transcription factor EHF interacting with coactivator AJUBA aggravates malignancy and acts as a therapeutic target for gastroesophageal adenocarcinoma

Transcriptional dysregulation of genes is a hallmark of tumors and can serve as targets for cancer drug development.However,it is extremely challenging to develop small-molecule inhibitors to target abnormally expressed transcription factors(TFs)except for the nuclear receptor family of TFs.Little is known about the interaction between TFs and transcription cofactors in gastroesophageal adenocarcinoma(GEA)or the therapeutic effects of targeting TF and transcription cofactor complexes.In this study,we found that ETS homologous factor(EHF)expression is promoted by a core transcriptional regulatory circuitry(CRC),specifically ELF3-KLF5-GATA6,and interference with its expression suppressed the malignant biological behavior of GEA cells.Importantly,we identified Ajuba LIM protein(AJUBA)as a new coactivator of EHF that cooperatively orchestrates transcriptional network activity in GEA.Furthermore,we identified KRAS signaling as a common pathway downstream of EHF and AJUBA.Applicably,dual targeting of EHF and AJUBA by lipid nanoparticles cooperatively attenuated the malignant biological behaviors of GEA in vitro and in vivo.In conclusion,EHF is upregulated by the CRC and promotes GEA malignancy by interacting with AJUBA through the KRAS pathway.Targeting of both EHF and its coactivator AJUBA through lipid nanoparticles is a novel potential therapeutic strategy.

Nuclear receptor coactivator 6 is a critical regulator of NLRP3 inflammasome activation and gouty arthritis

Transcriptional coactivators regulate the rate of gene expression in the nucleus.Nuclear receptor coactivator 6(NCOA6),a coactivator,has been implicated in embryonic development,metabolism,and cancer pathogenesis,but its role in innate immunity and inflammatory diseases remains unclear.Here,we demonstrated that NCOA6 was expressed in monocytes and macrophages and that its level was increased under proinflammatory conditions.Unexpectedly,nuclear NCOA6 was found to translocate to the cytoplasm in activated monocytes and then become incorporated into the inflammasome with NLRP3 and ASC,forming cytoplasmic specks.Mechanistically,NCOA6 associated with the ATP hydrolysis motifs in the NACHT domain of NLRP3,promoting the oligomerization of NLRP3 and ASC and thereby instigating the production of IL-1βand active caspase-1.Of note,Ncoa6 deficiency markedly inhibited NLRP3 hyperactivation caused by the Nlrp3^(R258W) gain-of-function mutation in macrophages.Genetic ablation of Ncoa6 substantially attenuated the severity of two NLRP3-dependent diseases,folic-induced acute tubular necrosis and crystal-induced arthritis,in mice.Consistent with these findings,NCOA6 was highly expressed in macrophages derived from gout patients,and NCOA6-positive macrophages were significantly enriched in gout macrophages according to the transcriptome profiling results.Conclusively,NCOA6 is a critical regulator of NLRP3 inflammasome activation and is therefore a promising target for NLRP3-dependent diseases,including gout.

Mitochondrial dysfunction in a rat model and the related risk of metabolic disorders

OBJECTIVE:To explore whether kidney Yang deficiency(KYD)is prone to metabolic disorders may be linked to impaired mitochondrial function in thermogenesis and metabolic tissues.METHODS:A rat model of KYD was used,which was established using Sprague Dawley rat dams with warm preference subjected to herbal treatment that can improve kidney Yang.The human relevance was confirmed by reduced serum corticosterone levels,and increased preference for warm location.RESULTS:KYD Rats were underdeveloped.Adenosinetriphosphate(ATP)production was reduced in the brown fat,but increased in the muscle.However,oxidative phosphorylated complexes to generate ATP and mitochondrial biogenesis marker were reduced in both tissues.When the second insult of high-fat diet(HFD)was introduced,KYD rats gained less weight yet developed more severe lipid and glucose metabolic disorders.This may be driven by disregulated liver gluconeogenesis marker forkhead box protein O1 and lipid metabolic regulator cholesterol 7 alpha-hydroxylase.CONCLUSION:KYD rats exhibited reduced mitochondrial function in the brown fat,but were partially compensated by skeletal muscle,associated with the phenotype of warm preference and metabolic disorder,which was further exacerbated by additional HFD consumption.Future studies can focus on treatment targetting mitochondria function to reverse this phenotype.

Coactivation Does Not Contribute to Fatigue-Induced Decreases in Isokinetic Forearm Flexion and Extension Torque

Purpose The present study examined the effects of a reciprocal,slow velocity forearm flexion and extension task on fatigue-induced changes in isokinetic torque,agonist and antagonist muscle activation,and coactivation ratios at slow and moderate velocities.Methods Nine women(mean±SD:age=21.0±1.7 years;body mass=68.1±8.2 kg;height=167.4±7.2 cm)completed pre-testing for forearm flexion and extension isokinetic peak torque at 60 and 180°/s,a fatiguing task of 50 maximal,recip-rocal,isokinetic muscle actions at 60°/s,and post-testing.The amplitude(AMP)of the electromyographic(EMG)signals from the biceps and triceps were simultaneously recorded.Torque and EMG AMP were normalized to the corresponding values from the pre-testing peak torque movements.Repeated measures ANOVAs and pairwise comparisons were used to identify mean changes in torque,EMG AMP,and coactivation ratios.Results The torque analyses indicated significant decreases from pre-to post-testing for forearm flexion(14.1%±5.0%;P<0.001)and extension(25.4%±12.2%;P<0.001)at 60°.At 180°/s there was a significant decrease,collapsed across the forearm movements(24.7%±11.7%;P<0.001).For EMG AMP and coactivation ratios,there were no changes(P>0.05)from pre-to post-testing for either velocity or movement.Conclusions The torque responses were velocity-specific,with greater fatigability exhibited for forearm extension versus flexion at 60°/s,but no differences at 180°/s.The parallel EMG AMP responses between the agonist and antagonist muscles for both velocities supported the lack of fatigue-induced changes in coactivation ratios.Thus,our results demonstrated that fatigue-induced decreases in torque were not attributable to increases in antagonist activation or coactivation.

Computational design of BC_(3)N_(2) based single atom catalyst for dramatic activation of inert CO_(2) and CH4 gasses into CH_(3)COOH with ultralow CH_(4) dissociation barrier

The production of CH_(3)COOH from CO_(2)and CH_(4) has stimulated much interest due to the high energy density of C2 species.Various kinds of catalysts have been developed while the high dissociation barrier of CH_(4) and low selectivity still hinders the efficiency of the reaction.We have herein proposed a novel catalyst with single metals loaded on 2D BC_(3)N_(2) substrate(M@2D-BC_(3)N_(2))based on density functional theory.Among numerous candidates,Pt@2D-BC_(3)N_(2) possesses the most favorable reactivity with an ultralow barrier of CH_(4) splitting(0.26 e V),which is due to the efficient capture ability of CH_(4) on Pt site.Besides,the selectivity for CH_(3)COOH is also very high,which mainly stems from the unique electronic properties of molecules and substrate:The degenerated states,including s,px,pyand pz,in CO_(2)reflects the existence of delocalizedπbonds between C and O.This can interact with states of Pt(s),Pt(pz),Pt(dxz),Pt(dyz),and Pt(z2)in Pt@2D-BC_(3)N_(2).The kinetics model also proves that our system can promote CH_(3)COOH production via simply increasing the temperature or the coverage of CH_(4) and CO_(2).Our results provide a reasonable illustration in clarifying mechanism and propose promising candidates with high reactivity for further study.