Interaction of major facilitator superfamily domain containing 2A with the blood-brain barrier

The functional and structural integrity of the blood-brain barrier is crucial in maintaining homeostasis in the brain microenvironment;however,the molecular mechanisms underlying the formation and function of the blood-brain barrier remain poorly understood.The major facilitator superfamily domain containing 2A has been identified as a key regulator of blood-brain barrier function.It plays a critical role in promoting and maintaining the formation and functional stability of the blood-brain barrier,in addition to the transport of lipids,such as docosahexaenoic acid,across the blood-brain barrier.Furthermore,an increasing number of studies have suggested that major facilitator superfamily domain containing 2A is involved in the molecular mechanisms of blood-brain barrier dysfunction in a variety of neurological diseases;however,little is known regarding the mechanisms by which major facilitator superfamily domain containing 2A affects the blood-brain barrier.This paper provides a comprehensive and systematic review of the close relationship between major facilitator superfamily domain containing 2A proteins and the blood-brain barrier,including their basic structures and functions,cross-linking between major facilitator superfamily domain containing 2A and the blood-brain barrier,and the in-depth studies on lipid transport and the regulation of blood-brain barrier permeability.This comprehensive systematic review contributes to an in-depth understanding of the important role of major facilitator superfamily domain containing 2A proteins in maintaining the structure and function of the blood-brain barrier and the research progress to date.This will not only help to elucidate the pathogenesis of neurological diseases,improve the accuracy of laboratory diagnosis,and optimize clinical treatment strategies,but it may also play an important role in prognostic monitoring.In addition,the effects of major facilitator superfamily domain containing 2A on blood-brain barrier leakage in various diseases and the research progress on cross-blood-brain barrier drug delivery are summarized.This review may contribute to the development of new approaches for the treatment of neurological diseases.

A major facilitator superfamily transporter PlMFS1 contributes to growth,oosporogenesis,and pathogenesis of Peronophythora litchii

Major facilitator superfamily(MFS)transporters are secondary active membrane transporters that play an important role in solute interchange and energy metabolism.Peronophythora litchii causes the most destructive disease on lichi,litchi downy blight.PlM90 was reported as a key oosporogenesis regulator.Here,we identified an MFS transporter gene PlMFS1,which is up-regulated during oospore formation at the late infection stage,while down-regulated in the PlM90 mutant.To investigate PlMFS1 function,we generated PlMFS1knockout mutants using CRISPR/Cas9-mediated genome editing technology.Compared with the wild-type strain SHS3,PlMFS1 deletion impaired mycelium growth,zoospore release,oospore production and pathogenicity.Furthermore,PlMFS1 deletion significantly affected P.litchii utilization of fructose,lactose and maltose,and may be the PlMFS1 mechanism involved in mycelial growth.PlMFS1 gene deletion also led to deceased laccase activity,laccase-encoding gene downregulation and impaired P.litchii pathogenicity.To our knowledge,this is the first report of an MFS transporter involved in sugar utilization,sexual reproduction,asexual reproduction and pathogenesis in oomycetes.

Potential role of transmembrane 9 superfamily member 1 as a biomarker in urothelial cancer

Bladder cancer is a urological tumor with high rates of recurrence despite recent advances in novel therapies.Many proteins involved in the molecular mechanisms are currently an enigma,especially the transmembrane 9 superfamily member 1 which has an unclear function.Wei et al published the function and mechanism of this protein,and showed that it could participate in the proliferation,migration and invasion of tumor cells in bladder cancer,therefore treatments directed against this protein may be beneficial in avoiding this condition.

Understanding the role of transmembrane 9 superfamily member 1 in bladder cancer pathogenesis

In this editorial we comment on the article by Wei et al,published in the recent issue of the World Journal of Clinical Oncology.The authors investigated the role of Transmembrane 9 superfamily member 1(TM9SF1)protein in bladder cancer(BC)carcinogenesis.Lentiviral vectors were used to achieve silencing or overexpression of TM9SF1 gene in three BC cell lines.These cell lines were then subject to cell counting kit 8,wound-healing assay,transwell assay,and flow cytometry.Proliferation,migration,and invasion of BC cells were increased in cell lines subjected to TM9SF1 overexpression.TM9SF1 silencing inhibited proliferation,migration and invasion of BC cells.The authors conclude that TM9SF1 may be an oncogene in bladder cancer pathogenesis.

A review of the recent advances in the systematics of the avian superfamily Sylvioidea

The systematics of the avian superfamily Sylvioidea are reviewed, focusing on studies of relationships among families and within genera, more superficially on taxonomic studies at the species level. For the families Bernieridae and Phylloscopidae, new analyses based on already published sequence data are presented. Our understanding of relationships has been vastly improved in recent years due to a large number of molecular studies. However, the relationships among the different families remain largely obscured, probably mainly as a result of rapid divergence of the different primary lineages (families). Also, species level taxonomy has been much improved in recent years due to a large number of studies applying molecular markers and/or vocalizations and other life-history data. It seems likely that the number of species will continue to increase, as new groups are being studied with modern integrative methods.

Human ribonuclease 9,a member of ribonuclease A superfamily,specifically expressed in epididymis,is a novel sperm-binding protein

To explore the functions of human ribonuclease 9(RNase 9),we constructed a mammalian fusion expression vector pcDNA-hRNase9,prepared recombinant human RNase 9-His fusion protein from HEK293T cells and determined its N-terminal amino acid sequences.According to the determined mature protein,recombinant human RNase 9 was prepared in E.coli.Ribonucleolytic activity and antibacterial activity of recombinant human RNase 9 were detected,and the distribution of human RNase 9 on tissues and ejaculated spermatozoa and in vitro capacitated spermatozoa were analyzed via indirect immunofluorescence assay.The results showed that recombinant human RNase 9 did not exhibit detectable ribonucleolytic activity against yeast tRNA,but exhibited antibacterial activity,in a concentration/time dependent manner,against E.coli.Immunofluorescent analyses showed that the predicted human RNase 9 was present throughout the epididymis,but not present in other tissues examined,and human RNase 9 was also present on the entire head and neck regions of human ejaculated spermatozoa and in vitro capacitated spermatozoa.These results suggest that human RNase 9 may play roles in host defense of male reproductive tract.

Molecular cloning and characterization of human age-related NADH oxidase (arNOX) proteins as members of the TM9 superfamily of transmembrane proteins

Age-related NADH oxidase (arNOX = ENOX3) proteins are superoxide-generating cell surface oxidases that increase in activity with age beginning at about 30 y. A soluble and truncated exfoliated form of the activity is present in blood and other body fluids. The activity was purified to apparent homogeneity from human urine and resolved by 2-D gel electrophoresis into a series of 24 to 32 kDa components of low isoelectric point. The purified proteins were resistant both to N-terminal sequencing and trypsin cleavage. Cleavage with pepsin revealed peptides corresponding to the TM9 family of transmembrane proteins. Peptide antisera raised to all five members of the human TM9 family sequentially blocked the arNOX activity of human saliva and sera. The soluble truncated N-terminus of the human homolog TM9SF4 was expressed in bacteria. The recombinant protein was characterized biochemically and exhibited ar-NOX activity. The findings identify five arNOX isoforms each of which correspond to one of the five known TM9 family members. The exfoliated soluble arNOX forms are derived from the 24 to 32 kDa N-termini exposed to the cell’s exterior at the cell surface. Each of the shed forms contain putative functional motifs characteristic of ECTO-NOX (ENOX) proteins despite only minimal sequence identity. Our findings identify arNOX as having functional characteristics of ENOX proteins and the TM9 superfamily of proteins as the genetic origins of the five known arNOX isoforms present in human sera, plasma and other body fluids1.

Correlation of tumor necrosis factor receptor superfamily 13B variation with sporadic intracranial aneurysm and clinical characteristics in Han Chinese populations

BACKGROUND： Inflammatory reaction correlates with sporadic intracranial aneurysm （IA）. Variation of tumor necrosis factor receptor superfamily 13B （TNFRSF13B）, an inflammatory mediator receptor, may associate with IA. OBJECTIVE： To explore the relationship between TNFRSF13B gene and sporadic IA, as well as the clinical characteristics of sporadic IA. DESIGN, TIME AND SETTING： Case-control study of genetic association was performed at the Experimental Technology Center of China Medical University from November 2006 to January 2008. PARTICIPANTS： A total of 367 patients with IA, confirmed by three-dimensional computed tomography angiography, magnetic resonance angiography, digital subtraction angiography, and neuro surgery, were admitted to the Department of Neurosurgery, First Affiliated Hospital of China Medical University from 2006 to 2007, and were selected as the case group. All patients were Han, with no family history of IA. In addition, a total of 396 non-lA patients were selected as control subjects. METHODS： Peripheral vein blood was harvested to extract whole blood genomic DNA. Genotyping and TNFRSF13B single nucleotide polymorphism （SNP） rs11078355 G〉A allele polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism. The relationship of TNFRSF13B SNP rs11078355 G〉A polymorphisms to IA and IA clinical characteristics were analyzed using the chi-square and two-sided test. MAIN OUTCOME MEASURES： TNFRSF13B SNP rs11078355 G〉A genotype distribution. RESULTS： In the IA patients, TNFRSF13B SNP rs11078355 G〉A genotype frequency was significantly increased （X2 = 16.306, odds ratio = 1.881,95% confidence interval = 1.382 2.560, P 〈 0.001）. In IA patients aged 〉 65 years, the frequency of TNFRSF13B SNP rs11078355 GA ＋ AA genotype was significantly greater than the GG genotype （X2 = 26.604, odds ratio = 5.248, 95% confidence interval = 2.662 10.345, P 〈 0.001）. CONCLUSION： The TNFRSF13B gene may associate with sporadic IA in Han Chinese populations In elderly patients, allele A may be an independent risk factor for IA, in addition to senile diseases, such as hypertension and diabetes mellitus.

Genome-Wide Characterization of the Cellulose Synthase Gene Superfamily in Tea Plants(Camellia sinensis)

The cellulose synthase gene superfamily,including Cellulose synthase A(CesA)and cellulose synthase-like(Csl)gene families,is responsible for the synthesis of cellulose and hemicellulose,respectively.The CesA/Csl genes are vital for abiotic stress resistance and shoot tenderness regulation of tea plants(Camellia sinensis).However,the CesA/Csl gene family has not been extensively studied in tea plants.Here,we identified 53 CsCesA/Csl genes in tea plants.These genes were grouped into five subfamilies(CsCesA,CsCslB,CsCslD,CsCslE,CsCslG)based on the phylogenetic relationships with Arabidopsis and rice.The analysis of chromosome distribution,gene structure,protein domain and motif revealed that most genes in CsCesA,CsCslD and CsCslE subfamilies were conserved,whereas CsCslB and CsCslG subfamily members are highly diverged.The transcriptome analysis showed that most CsCesA/Csl genes displayed tissue-specific expression pattern.In addition,members of CsCslB4,CsCesA1/3/6,CsCslB3/4,CsCslD3,CsCslE1 and CsCslG2/3 subfamilies were up-regulated under drought and cold stresses,indicating their potential roles in regulating stress tolerance in tea plants.Furthermore,the expression levels of CsCslG2_6 and CsCslD3_5 in different tissues and cultivars,respectively,were positively correlated with the cellulose content that is negatively related with shoot tenderness.Thus,these two genes were speculated to be involved in the regulation of shoot tenderness in tea plants.Our findings may help elucidate the evolutionary relationships and expression patterns of the CsCesA/Csl genes in tea plants,and provide more candidate genes responsible for stress tolerance and tenderness regulation in tea plants for future functional research.

Tumor necrosis family receptor superfamily member 9/tumor necrosis factor receptor-associated f

Hepatitis C virus(HCV)infection is an excellent immunological model for understanding the mechanisms developed by non-cytopathic viruses and tumors to evade the adaptative immune response.The antigen-specific cytotoxic T cell response is essential for keeping HCV under control,but during persistent infection,these cells become exhausted or even deleted.The exhaustion process is progressive and depends on the infection duration and level of antigenemia.During high antigenic load and long duration of infection,T cells become extremely exhausted and ultimately disappear due to apoptosis.The development of exhaustion involves the impairment of positive co-stimulation induced by regulatory cytokines,such as transforming growth factor beta 1.This cytokine downregulates tumor necrosis factor receptor(TNFR)-associated factor 1(TRAF1),the signal transducer of the T cell co-stimulatory molecule TNFR superfamily member 9(known as 4-1BB).This impairment correlates with the low reactivity of T cells and an exhaustion phenotype.Treatment with interleukin-7 in vitro restores TRAF1 expression and rescues T cell effector function.The process of TRAF1 loss and its in vitro recovery is hierarchical,and more affected by severe disease progression.In conclusion,TRAF1 dynamics on T cells define a new pathogenic model that describes some aspects of the natural history of HCV,and sheds light on novel immunotherapy strategies for chronic viral infections and cancer.

Utility of adeno-associated viruses to target members of the TGF-<i>β</i>superfamily in prostate cancer therapy

Components of the TGF-β superfamily have been well established in their intricate and multifaceted roles in cancer progression and survival. The TGF-βs have been targeted therapeutically in an attempt to modify complex tumour networks to favour cancer cell destruction. Goals of these therapies are often to attack the “hallmarks” of cancer: characteristics acquired by cancer cells via re-wiring or manipulating existing biological pathways to their survival advantage. Of the multitude of targeted therapies currently available, viral therapies have shown much promise in their efficacy of treatment. This review highlights current viral therapies targeting members of the TGF-β superfamily, with a focus on the strengths and limitations associated with this form of targeted cancer therapy.

GmDFB1,an ARM-repeat superfamily protein,regulates floral organ identity through repressing siRNA-and miRNA-mediated gene silencing in soybean

The development of flowers in soybean(Glycine max)is essential for determining the yield potential of the plant.Gene silencing pathways are involved in modulating flower development,but their full elucidation is still incomplete.Here,we conducted a forward genetic screen and identified an abnormal flower mutant,deformed floral bud1-1(Gmdfb1-1),in soybean.We mapped and identified the causal gene,which encodes a member of the armadillo(ARM)-repeat superfamily.Using small RNA sequencing(sRNA-seq),we found an abnormal accumulation of small interfering RNAs(si RNAs)and microRNA(miRNAs)in the Gmdfb1 mutants.We further demonstrated that GmDFB1 interacts with the RNA exosome cofactor SUPER KILLER7(Gm SKI7).Additionally,GmDFB1 interacts with the PIWI domain of ARGONAUTE 1(GmAGO1)to inhibit the cleavage efficiency on the target genes of s RNAs.The enhanced gene silencing mediated by siRNA and miRNA in the Gmdfb1 mutants leads to the downregulation of their target genes associated with flower development.This study revealed the crucial role of GmDFB1 in regulating floral organ identity in soybean probably by participating in two distinct gene silencing pathways.

A new method of research on molecular evolution of proteinase superfamily

The molecular evolutionary tree, also known as a phylogenetic tree, of the serine proteinase superfamily was constructed by means of structural alignment. Three-dimensional structures of proteins were aligned by the SSAP program of Orengo and Taylor to obtain evolutionary distances. The resulting evolutionary tree provides a topology graph that can reflect the evolution of structure and function of homology proteinase. Moreover, study on evolution of the serine proteinase superfamily can lead to better understanding of the relationship and evolutionary difference among proteins of the superfamily, and is of significance to protein engineering, molecular design and protein structure prediction. Structure alignment is one of the useful methods of research on molecular evolution of protein.

Effect of Wenhua Juanbi Recipe(温化蠲痹方) on Expression of Receptor Activator of Nuclear Factor Kappa B Ligand,Osteoprotegerin,and Tumor Necrosis Factor Receptor Superfamily Member 14 in Rats with Collagen-Induced Arthritis

Objective： To study the effect of Wenhua Juanbi Recipe（温化蠲痹方, WJR） on expression of receptor activator of nuclear factor kappa B ligand（RANKL）, osteoprotegerin（OPG）, and tumor necrosis factor receptor superfamily member 14（TNFRSF14, also known as LIGHT） in rats with collagen-induced arthritis（CIA）. Methods： CIA rats were generated by subcutaneous injection of bovine collagen type-Ⅱ at the tail base. Sixty CIA rats were randomly assigned（10 animals/group） to： model, methotrexate（MTX）-treated（0.78 mg/kg body weight）, and WJR-treated（22.9 g/kg） groups. Healthy normal rats（n=10） were used as the normal control. Treatments or saline were administered once daily by oral gavage. Rats were sacrificed at day 28 post-treatment and knee synovium and peripheral blood serum were collected. Toe swelling degree and expression of RANKL, OPG, and LIGHT were determined by Western blot and immunohistochemistry. Results： Compared with the normal group, toe swelling degree was significantly increased in the model group（P〈0.01）. After treatment, toe swelling degree decreased significantly in the WJR and MTX groups compared with the model group（P〈0.01）. Compared with the normal group, expression of RANKL and LIGHT were significantly increased and OPG significantly decreased in peripheral blood and synovium of the model group（P〈0.01）. Conversely, RANKL and LIGHT expression were significantly reduced and OPG increased in the WJR and MTX groups compared with the model group（P〈0.01）. No statistically significant difference existed between WJR and MTX groups. Conclusion： WJR likely acts by reducing RANKL expression and increasing OPG expression, thus inhibiting RANKL/RANK interaction and reducing LIGHT expression, thereby inhibiting osteoclast formation/activation to block bone erosion.

Identification of protein superfamily from structure-based sequence motif

The structure-based sequence motif of the distant proteins in evolution, protein tyrosine phosphatases (PTP) I and Ⅱ superfamilies, as an example, has been defined by the structural comparison, structure-based sequence alignment and analyses on substitution patterns of residues in common sequence conserved regions. And the phosphatases I and Ⅱ can be correctly identified together by the structure-based PTP sequence motif from SWISS-PROT and TrEBML databases. The results show that the correct rates of identification are over 98%. This is the first time to identify PTP I and Ⅱ together by this motif.

THE VACCINIA VIRUS HindⅢ K FRAGMENT ENCODES A NOVEL PROTEIN BELONGING TO THE SERPIN SUPERFAMILY

The 1893-base pair nucleotide sequence of the EcoRⅠ-HindⅢ fragment of vaccinia virus Tiantan strain HindⅢ K clone is determined by the dideoxy chain termination method. A search in the NBRF protein sequence database using FASTA and other microcomputer programs reveals that several proteins belonging to the serpin (serine protease inhibitor) superfamily have striking similarities to tho protein encoded by the HindⅢ Kl ORF. On the basis of the dot-matrix analysis and sequence alignment, the Kl-encoded protein is shown as a novel member of the serpin superfamily. The putative reactive site and switch sequence of this novel serpin are then compared with those of other serpins. The probable evolutionary and possible functional relationships are discussed.

Identification and modulation of expression of a TNF receptor superfamily member 25 homologue in grass carp (Ctenopharyngodon idella)

The TNF receptor superfamily member 25(TNFRSF25)is part of the tumor necrosis factor receptor superfamily and contains a typical death domain.It is also known as DR3,TRAMP,LARD,WSL-1,Apo-3 and TR3,and has a vital role in regulating cell proliferation,differentiation and apoptosis.In this study,a homologue of the TNFRSF25 gene was identified in grass carp(Ctenopharyngodon idella).It encodes a transmembrane protein with an extracellular domain containing a cysteine-rich domain and an intracellular domain containing a death domain.It is an orthologue of fish TNFRSF1ALs and shares conserved gene synteny with human TNFRSF25.Expression studies showed that CiTNFRSF25 was constitutively expressed in the majority of fish tissues and can be modulated by interleukin 4/13B and infection by F.columnare.To our knowledge,this is the first report describing the existence of a TNFRSF25 homologue in teleost fish.

Tumor necrosis factor receptor superfamily member 9 is upregulated in the endothelium and tumor cells in melanoma brain metastasis

Aim:The cytokine receptor tumor necrosis factor receptor superfamily member 9(TNFRSF9)is mainly considered to be a co-stimulatory activation marker in hematopoietic cells.Several preclinical models have shown a dramatic beneficial effect of treatment approaches targeting TNFRSF9 with agonistic antibodies.However,preliminary clinical phase I/II studies were stopped after the occurrence of several severe deleterious side effects.In a previous study,it was demonstrated that TNFRSF9 was strongly expressed by reactive astrocytes in primary central nervous system(CNS)tumors,but was largely absent from tumor or inflammatory cells.The aim of the present study was to address the cellular source of TNFRSF9 expression in the setting of human melanoma brain metastasis,a highly immunogenic tumor with a prominent tropism to the CNS.Methods:Melanoma brain metastasis was analyzed in a cohort of 78 patients by immunohistochemistry for TNFRSF9 and its expression was correlated with clinicopathological parameters including sex,age,survival,tumor size,number of tumor spots,and BRAF V600E expression status.Results:Tumor necrosis factor receptor superfamily member 9 was frequently expressed independently on both melanoma and endothelial cells.In addition,TNFRSF9 was also present on smooth muscle cells of larger vessels and on a subset of lymphomonocytic tumor infiltrates.No association between TNFRSF9 expression and patient survival or other clinicopathological parameters was seen.Of note,several cases showed a gradual increase in TNFRSF9 expression on tumor cells with increasing distance from blood vessels,an observation that might be linked to hypoxia-driven TNFRSF9 expression in tumor cells.Conclusion:The findings indicate that the cellular source of TNFRSF9 in melanoma brain metastasis largely exceeds the lymphomonocytic pool,and therefore further careful(re-)assessment of potential TNFRSF9 functions in cell types other than hematopoietic cells is needed.Furthermore,the hypothesis of hypoxia-driven TNFRSF9 expression in brain metastasis melanoma cells requires further functional testing.

Do tensile and shear forces exerted on cells influence mechanotransduction through stored energy considerations?

All tissues in the body are subjected externally to gravity and internally by collagenfibril and cellular retractive forces that create stress and energy equilibrium required for homeostasis.Mechanotransduction involves mechanical work(force through a distance)and energy storage as kinetic and potential energy.This leads to changes in cell mitosis or apoptosis and the synthesis or loss of tissue components.It involves the application of energy directly to cells through integrin-mediated processes,cell-cell connections,stretching of the cell cytoplasm,and activation of the cell nucleus via yes-associated protein(YAP)and transcriptional coactivator with PDZ-motif(TAZ).These processes involve numerous complexes,intermediate molecules,and multiple pathways.Several pathways have been identified from research studies on vertebrate cell culture and from studies in invertebrates.These pathways involve mechanosensors and other molecules that activate the pathways.This review discusses the mitogen-activated protein kinase(MAPK)family,Hippo,Hedgehog,and Wingless-related integration site(WNT)/βcatenin signaling pathways.The mediators covered includeβcatenin,ion channels,growth factors,hormone receptors,members of the Ras superfamily,and components of the linker of nucleoskeleton and cytoskeleton(LINC)complex.However,the interrelationship among the different pathways remains to be clarified.Integrin-mediated mechanotransduction involves direct tensile loading and energy applied to the cell membrane via collagenfibril stretching.This energy is transferred between cells by stretching the cell-cell connections involving cadherins and the WNT/βcatenin pathway.These alterations induce changes in intracellular events in the cytoskeleton and nuclear skeleton caused by the release of YAP and TAZ.These coactivators then penetrate through the nuclear pores and influence nuclear cell function.Alteration in the balance of forces and energy applied to cells and tissues is hypothesized to shift the cell-extracellular matrix mechanical equilibrium by modifying mechanotransduction.The shift in equilibrium can lead to either tissue synthesis,genetic modifications,or promotefibrotic diseases,including epithelial cell-derived cancers,depending on the local metabolic conditions.

Human AKR1A1 involves in metabolic activation of carcinogenic aristolochic acidⅠ

OBJECTIVE To investigate whether aldo-keto reductases(AKRs)can act as a nitrore⁃ductase(NR)and bioactivate aristolochic acidⅠ(AA-Ⅰ)to produce AA-Ⅰ-DNA adducts.METHODS①Human-induced hepatocytes(hiHeps)and human bladder RT4 cells were used as tool cells and treated with AA-Ⅰ0,0.5,1.0 and 2μmol·L^(-1)for 24 h.Cell viability was detected using the CCK-8 method,and the half maximal inhibition concentration(IC_(50))was calculated using the CCK-8 method and the level of DNA adduct production was calculated.②hiHeps and RT4 cells were treated with AKR inhibitor luteotin(0,5,10 and 25μmol·L^(-1))+AA-Ⅰ0.2 and 1.0μmol·L^(-1)for 24 h,respectively,and the levels of DNA adducts were detected by a liquid chromatography-tandem mass spectrometer(LC-MS/MS).③hiHeps cells were incubated with 80 nmol·L^(-1)small interfering RNAs(si-AKRs)for 48 h and treated with AA-Ⅰ1.0μmol·L^(-1)for 24 h.Real-time qualitative PCR(RT-qPCR)method was used to detect the mRNA expression of AKRs gene and LC-MS/MS technology was used to investigate the effect of specific AKR gene knockdown on DNA adduct levels.④500 nmol·L^(-1)human AKR recombinant proteins AKR1A1 and AA-Ⅰwere incubated in vitro under anaerobic conditions and the formation of AA-Ⅰ-DNA adducts was detected.RESULTS①The IC_(50)of AA-Ⅰto hiHeps and RT4 cells was 1.9 and 0.42μmol·L^(-1),respec⁃tively.The level of DNA adduct production of the two cell lines was significantly different(P<0.01).②Luteolin≥5μmol·L^(-1)significantly inhibited the production of AA-Ⅰ-DNA adducts in both cells(P<0.05),and there was a concentration-dependent effect in hiHeps cells(P<0.01,R=0.84).③In the AKR family,the knockdown of AKR1A1 gene up to 80%inhibited the generation of AA-Ⅰ-DNA adducts by 30%-40%.④The AA-Ⅰ-DNA adducts were detected in the incubation of recombinant protein AKR1A1 and AA-Ⅰunder anaerobic conditions in vitro,approximately 1 adduct per 107 nucleotides.CONCLU⁃SION AKR1A1 is involved in AA-Ⅰbioactivation,providing a reference for elucidation of the carcino⁃genic mechanism of AA-Ⅰ.