[Objective]The aim was to clone TapⅡchalcone isomerases（CHI1 A） from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone i...[Objective]The aim was to clone TapⅡchalcone isomerases（CHI1 A） from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone isomerases（CHI1 A） was cloned by RTPCR method,and it was sequenced after cloning into pMD18-T vectors,and recombined to expression vector PNZ8149-CHI1 A,then it was transformed into Lactococcus Lactis NZ3900[Result]The sequencing results indicated that the cloned fragment of CHI1 A contained 670 nucleotides,and shared a sequence homology of 92% with that from Genbank accession number AF595413（CHI1 A）.CHI1 A was transformed into NICE expression system successfully by identification of PCR and digestion.[Conclusion]The foundation of using the microorganism fermentation method to produce flavonoids was laid by construction of efficient induction expression vector with chalcone isomerases CHI1 A.展开更多
The chalcone isomerase gene OsCHI,one of the key genes in the flavonoid biosynthesis pathway,plays an important role in rice(Oryza sativa)resistance to abiotic stresses.This study reveals how the chalcone isomerase ge...The chalcone isomerase gene OsCHI,one of the key genes in the flavonoid biosynthesis pathway,plays an important role in rice(Oryza sativa)resistance to abiotic stresses.This study reveals how the chalcone isomerase gene family member OsCHI3 participates in rice responses to drought stress through the regulation of flavonoid biosynthesis.Overexpression of OsCHI3 increased the tolerance of rice to drought stress.In contrast,CRISPR/Cas9-mediated deletion of OsCHI3 reduced the drought tolerance of rice,an effect that is reversed by exogenous ABA treatment.Transcriptomic and physiological biochemical analyses indicated that flavonoids regulated by OsCHI3 not only scavenge reactive oxygen species(ROS)but also increase drought tolerance in rice by stimulating ABA biosynthesis through the regulation of OsNCED1 and OsABA8ox3 expression.These findings demonstrate that OsCHI3 increases drought stress tolerance in rice by activating the antioxidant defense system and the ABA metabolic pathway,providing new clues for drought-resistant rice breeding research.展开更多
Creutzfeldt-Jakob disease(CJD)is a rare neurodegenerative disorder characterized by abnormalities in the prion protein(PrP),the most common form of human prion disease.Although Genome-Wide Association Studies(GWAS)hav...Creutzfeldt-Jakob disease(CJD)is a rare neurodegenerative disorder characterized by abnormalities in the prion protein(PrP),the most common form of human prion disease.Although Genome-Wide Association Studies(GWAS)have identified numerous risk genes for CJD,the mechanisms underlying these risk loci remain poorly understood.This study aims to elucidate novel genetically prioritized candidate proteins associated with CJD in the human brain through an integrative analytical pipeline.Utilizing datasets from Protein Quantitative Trait Loci(pQTL)(NpQTL1=152,NpQTL2=376),expression QTL(eQTL)(N=452),and the CJD GWAS(NCJD=4110,NControls=13569),we implemented a systematic analytical pipeline.This pipeline included Proteome-Wide Association Study(PWAS),Mendelian randomization(MR),Bayesian colocalization,and Transcriptome-Wide Association Study(TWAS)to identify novel genetically prioritized candidate proteins implicated in CJD pathogenesis within the brain.Through PWAS,we identified that the altered abundance of six brain proteins was significantly associated with CJD.Two genes,STX6 and PDIA4,were established as lead causal genes for CJD,supported by robust evidence(False Discovery Rate<0.05 in MR analysis;PP4/(PP3+PP4)≥0.75 in Bayesian colocalization).Specifically,elevated levels of STX6 and PDIA4 were associated with an increased risk of CJD.Additionally,TWAS demonstrated that STX6 and PDIA4 were associated with CJD at the transcriptional level.展开更多
Rice blast,caused by Magnaporthe oryzae,is a fungal disease that causes devastating damage to rice production worldwide.During infection,pathogens secrete effector proteins that modulate plant immunity.Disulfide bond ...Rice blast,caused by Magnaporthe oryzae,is a fungal disease that causes devastating damage to rice production worldwide.During infection,pathogens secrete effector proteins that modulate plant immunity.Disulfide bond formation catalyzed by protein disulfide isomerases(PDI)is essential for protein folding and maturation.However,the biological function of Pdi1 in M.oryzae has not yet been characterized.In this study,we identified the endoplasmic reticulum(ER)-located protein,MoPdi1,in M.oryzae.MoPdi1 regulates conidiation,cell wall stress,and pathogenicity of M.oryzae.Furthermore,the CGHC active sites in the a and a'redox domain of MoPdi1 were essential for the biological function of MoPDI1.Further tests demonstrated that MoPdi1 was involved in the regulation of ER stress and positively regulated ER phagy.We also found that MoPdi1 interacted with MoHut1.Deletion of MoPDI1 led to the bereft of MoHut1 dimerization,which depends on the formation of disulfide bonds.In addition,MoPdi1 affected the normal secretion of the cytoplasmic effector AVR-Pia.We provided evidence that MoHut1 is important for the vegetative growth,conidiation,and pathogenicity in M.oryzae.Therefore,our findings could provide a suitable target point for designing antifungal agrochemicals against rice blast fungus.展开更多
pdi gene from Medicago sativa L. ,encoding Protein Disulfide Isomerase（ mPDI ）, has been cloned and sequenced. According to the mRNA and amino acid sequence, the character of mPDI such as the physical and chemical p...pdi gene from Medicago sativa L. ,encoding Protein Disulfide Isomerase（ mPDI ）, has been cloned and sequenced. According to the mRNA and amino acid sequence, the character of mPDI such as the physical and chemical properties, hydrophilicity/hydrophobicity, signal peptide, secondary structure, coiled coil, transmembrane domains, O-glycogylation site, active site, subcellular localization, functional structural domains and three-dimensional structure were analyzed by a series of bioinformatics software. The results showed that mPDI was a hydrophobic and stable protein with 3 coiled coils, 30-glycogylation sites, 2 structural domains of thioredoxin, 2 active sites of thioredoxin, and located in rough endoplasmic reticulum. It has 512 amino acids, the theoretical pl is 4.98, and signal peptide located in 1-24AA. In the secondary structure, a-helix, random coil, extended chain is 26.37%, 53.32%, 20.31% respectively. The validation of modeling accords with the stereochemistry.展开更多
The unicellular green alga Haematococcus pluvia/is uniquely accumulates carotenoids in the cytoplasm and in late developmental stages turns deep-red in color because of accumulation of astaxanthin in the cytosol. The ...The unicellular green alga Haematococcus pluvia/is uniquely accumulates carotenoids in the cytoplasm and in late developmental stages turns deep-red in color because of accumulation of astaxanthin in the cytosol. The enzyme, isopentenyl pyrophosphate （IPP） isomerase, plays a key role in astaxanthin biosynthesis of H. pluvialis. In this paper, two separate 5＇-flanking regions （1.8 kb and 2.5 kb） of IPP isomerase gene was cloned through walking upstream firstly. Results of sequence analysis =showed that two separate 5＇-flanking regions of IPP isomerase gene might have similar putative cis-acting elements such as ABA （abscisic acid）-responsive element （ABRE）, drought-responsive element （DRE/C-repeat）, light-responsive element （G-box, GAG-motif, I-box and ATC-motif）, heat-shock element （HSE）, wound-responsive element （WUN-motif）, SA （salicylic acid）-responsive element （TCA-element）, auxin-responsive element （TGA-element）, MeJA （methyl jasmonate）-responsive element （TGACG-element）, enhancer-like element involved in anoxic specific inducibility （GC-motif） and MYB binding sites （MBS and MRE）, except for typical TATA box or CCAAT box, which exhibit diversiform transcriptional patterns of IPP isomerase gene in astaxanthin biosynthesis of Haematococcus pluvialis.展开更多
This study analyzed and predicted following aspects of isopentenyl py- rophosphate isomerases （IPIs） of five north medicinal plants using bioinformatics methods and tools： physical and chemical properties, hydropho...This study analyzed and predicted following aspects of isopentenyl py- rophosphate isomerases （IPIs） of five north medicinal plants using bioinformatics methods and tools： physical and chemical properties, hydrophobicity/hydrophilicity, trans-membrane domain, secondary structure, subcellular localization and so on. The results showed that： there was no notable difference among the physical and chem- ical properties of IPIs of the five north medicinal plants; the IPIs were mainly hy- drophilic; the IPIs were mainly located in chloroplasts by subcellular localization; serine phosphorylation sites were the most; the secondary structures mainly consist- ed of c^-helixes and random coils; no signal peptide existed, indicating that the pro- tein IPI was non-secreted protein; no trans-membrane domain existed; and one functional domain was shown, Le., Nudix Hydrolase Superfamily. This study is of great significance to research on IPI gene functions, deep research on north medic- inal plants, improvement of efficacy of north medicinal plants and rational develop- ment and utilization of medicinal plant resources.展开更多
[Objective] The aim was to clone triosephosphate isomerase （TPI） gene from Apis mellifera, and predict the properties of TPI protein with bioinformatic meth- ods. [Method] The TPI gene was firstly cloned by in silic...[Objective] The aim was to clone triosephosphate isomerase （TPI） gene from Apis mellifera, and predict the properties of TPI protein with bioinformatic meth- ods. [Method] The TPI gene was firstly cloned by in silico cloning based on the ex- pressed sequence tags （ESTs） from Unigene of NCBI. Some characters of the TPI protein including hydrophobicity or hydrophilicity, isoelectric point （pl） and secondary structure were analyzed and predicted by the tools of bioinformatics. [Result] The TPI gene from A. mellifera was 1 768 bp in full length and it contained a complete ORF which encoded 247 amino acids; the pl of TPI protein was 8.515; the TPI protein was a member of ~13-fold family. [Conclusion] The in silico cloning based on the expressed sequence tags is a efficient method in practice, and this study will provide more references for further study on A. mellifera at molecular level.展开更多
Phosphomannose isomerase （PMI） encoding gene manA is a desirable selective marker in transgenic research. Under- standing of its expression patterns in transgenic plant and establishing highly sensitive detection me...Phosphomannose isomerase （PMI） encoding gene manA is a desirable selective marker in transgenic research. Under- standing of its expression patterns in transgenic plant and establishing highly sensitive detection method based on immunoassay have great impacts on the application of PMI. In this study, PMI-specific monoclonal antibodies were generated using recombinant protein as immunogen, and could be used in Western blot to detect as little as 0.5 ng His-tagged PMI protein or rice expressed PMI protein in sample accounted for 0.4% of single rice grain （about 0.08 mg）. PMI protein driven by CaMV-35S promoter was detected in dozens of tested tissues, including root, stem, leaf, panicle, and seed at all developmental stages during rice growing, and PMI protein accounted for about 0.036% of total protein in the leaves at seedling stage. The established method potentially can be used to monitor PMI protein in rice grains.展开更多
The limited treatment options for advanced prostate cancer(PCa)lead to the urgent need to discover new anticancer drugs.Mannose,an isomer of glucose,has been reported to have an anticancer effect on various tumors.How...The limited treatment options for advanced prostate cancer(PCa)lead to the urgent need to discover new anticancer drugs.Mannose,an isomer of glucose,has been reported to have an anticancer effect on various tumors.However,the anticancer effect of mannose in PCa remains unclear.In this study,we demonstrated that mannose inhibits the proliferation and promotes the apoptosis of PCa cells in vitro,and mannose was observed to have an anticancer effect in mice without harming their health.Accumulation of intracellular mannose simultaneously decreased the mitochondrial membrane potential,increased mitochondrial and cellular reactive oxygen species(ROS)levels,and reduced adenosine triphosphate(ATP)production in PCa cells.Mannose treatment of PCa cells induced changes in mitochondrial morphology,caused dysregulated expression of the fission protein,such as fission,mitochondrial 1(FIS1),and enhanced the expression of proapoptotic factors,such as BCL2-associated X(Bax)and BCL2-antagonist/killer 1(Bak).Furthermore,lower expression of mannose phosphate isomerase(MPI),the key enzyme in mannose metabolism,indicated poorer prognosis in PCa patients,and downregulation of MPI expression in PCa cells enhanced the anticancer effect of mannose.This study reveals the anticancer effect of mannose in PCa and its clinical significance in PCa patients.展开更多
Spinal cord ischemia/reperfusion injury is a stress injury to the spinal cord. Our previous studies using differential proteomics identified 21 differentially expressed proteins （n 〉 2） in rabbits with spinal cord ...Spinal cord ischemia/reperfusion injury is a stress injury to the spinal cord. Our previous studies using differential proteomics identified 21 differentially expressed proteins （n 〉 2） in rabbits with spinal cord ischemia/reperfusion injury. Of these proteins, stress-related proteins included protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70. In this study, we established New Zealand rabbit models of spinal cord ischemia/reperfusion injury by abdominal aorta occlusion. Results demonstrated that hind limb function initially improved after spinal cord ischemia/reperfusion injury, but then deteriorated. The pathological morphology of the spinal cord became aggravated, but lessened 24 hours after reperfusion. However, the numbers of motor neurons and interneurons in the spinal cord gradually decreased. The expression of protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70 was induced by ischemia/reperfusion injury. The expression of these proteins increased within 12 hours after reperfusion, and then decreased, reached a minimum at 24 hours, but subsequently increased again to similar levels seen at 6-12 hours, showing a characterization of induction-inhibition-induc- tion. These three proteins were expressed only in cytoplasm but not in the nuclei. Moreover, the expression was higher in interneurons than in motor neurons, and the survival rate of interneurons was greater than that of motor neurons. It is assumed that the expression of stress-related proteins exhibited a protective effect on neurons.展开更多
Objective: Tumor heterogeneity renders identification of suitable biomarkers of gastric cancer(GC)challenging. Here, we aimed to identify prognostic genes of GC using computational analysis.Methods: We first used micr...Objective: Tumor heterogeneity renders identification of suitable biomarkers of gastric cancer(GC)challenging. Here, we aimed to identify prognostic genes of GC using computational analysis.Methods: We first used microarray technology to profile gene expression of GC and paired nontumor tissues from 198 patients. Based on these profiles and patients’ clinical information, we next identified prognostic genes using novel computational approaches. Phosphoglucose isomerase, also known as glucose-6-phosphate isomerase(GPI), which ranked first among 27 candidate genes, was further investigated by a new analytical tool namely enviro-geno-pheno-state(E-GPS) analysis. Suitability of GPI as a prognostic marker, and its relationship with physiological processes such as metabolism, epithelial-mesenchymal transition(EMT), as well as drug sensitivity were evaluated using both our own and independent public datasets.Results: We found that higher expression of GPI in GC correlated with prolonged survival of patients.Particularly, a combination of CDH2 and GPI expression effectively stratified the outcomes of patients with TNM stage Ⅱ/Ⅲ. Down-regulation of GPI in tumor tissues correlated well with depressed glucose metabolism and fatty acid synthesis, as well as enhanced fatty acid oxidation and creatine metabolism, indicating that GPI represents a suitable marker for increased probability of EMT in GC cells.Conclusions: Our findings strongly suggest that GPI acts as a novel biomarker candidate for GC prognosis,allowing greatly enhanced clinical management of GC patients. The potential metabolic rewiring correlated with GPI also provides new insights into studying the relationship between cancer metabolism and patient survival.展开更多
The complex model of Thermus thermophilus xylose isomerase （TtXI） with D-xylose was constructed, and molecular dynamics （MD） simulations were carried out at 300 and 360 K for 10 ns by NAMD2.5. The radius of gyrati...The complex model of Thermus thermophilus xylose isomerase （TtXI） with D-xylose was constructed, and molecular dynamics （MD） simulations were carried out at 300 and 360 K for 10 ns by NAMD2.5. The radius of gyration （Rg）, subunit interactions, and residue flexibility were analyzed. The results show that residues 60-69, 142-148, 169-172, and 332-340 have high flexibility at 300 and 360 K. Residues with higher flexibility at 360 K than that at 300 K can mainly be divided into two groups： one locates in the helix-loophelix region consisting of residues 55-80 in catalytic domain; the other at subunit interfaces. The Rg of catalytic domain at 360 K shows 0.16 A higher than that at 300 K, but Rg of small C-terminal domain has no obvious difference. The results indicate that enhanced Rg of catalytic domain may lead to the intense motion of the active site of TtXI and promote the D-xylose isomization reaction. Eight hydrogen bonds and five ion pairs are reduced at subunit interfaces at 360 K compared with 300 K, that may be the main reason for the decrease in rigidity and increase in activity at high temperature of TtXI. This result also help to explain the cold-adaption phenomenon of TtXI E372G mutant reported previously. Our results reveal the relationship between temperature and structure flexibility of TtXI, and play an important role in understanding the thermostability of thermophile protein with multiple subunits.展开更多
L-arabinose isomerase (L-AI) is the key enzyme for D-galactose isomerization of D-tagatose by biological method. In this research, Lactobacillus plantarum WU14 with high D-tagatose yield was identified as Lactobacillu...L-arabinose isomerase (L-AI) is the key enzyme for D-galactose isomerization of D-tagatose by biological method. In this research, Lactobacillus plantarum WU14 with high D-tagatose yield was identified as Lactobacillus plantarum was isolated from the number of lactic acid bacteria from pickled vegetables. The crude L-arabinose isomerase activity of Lactobacillus plantarum WU14 with high D-tagatose yield was 13.95 U/mL under the optimal temperature 60°C, pH 7.17 and substrate concentration 0.8 mol/L, and the conversion rate of 56.12% could be gained after 28 hours. Protein structure and specific of L-Arabinose Isomerase of Lactobacillus plantarum WU14 were researched. The results showed that L-arabinose isomerase is mainly composed of alpha helix and random coil. Then the recombinant L-AI gene was inserted into the food-grade expression vector pRNA48 and expressed in L. lactis NZ9000 successfully. The target protein expression reached the maximum amount when the induced concentration of nisin reaches 30 ng/mL after 12 h. And the crude enzyme activity of recombinant bacteria reached 6.21 U/mL under 60°C. Otherwise the optimal conversion rate recombinant of L. lactis NZ9000/pRNA48-L-AI can reach 39.21% under the temperature of 50°C, pH 7.17 and D-galactose concentration was 0.6 mol/L.展开更多
Phosphoglucose isomerase (PGI) is a key enzyme in early glycolysis, which catalyzes the reversible isomerization of glucose 6-phosphate (G6Ph) to fructose 6-phosphate. We have constructed an Escherichia coli K12 strai...Phosphoglucose isomerase (PGI) is a key enzyme in early glycolysis, which catalyzes the reversible isomerization of glucose 6-phosphate (G6Ph) to fructose 6-phosphate. We have constructed an Escherichia coli K12 strain with a deleted pgi gene (Δpgi) and shown that this strain in comparison with the parental strain 1) accumulates higher amount of G6Ph, 2) grows slowly, and 3) exhibits higher spontaneous mutation frequency to rifampicin resistance (Rifr), when grown on high glucose minimal medium. Intriguingly, the spontaneous mutation rate to Rifr was inversely related to the degree of E. coli chromosomal DNA modification with sugar derivatives. We measured higher concentrations of Amadori products, fluorophores (360 nm excitation/440 nm emission) and carboxymethyl residues in the chromosomal DNA of the E. coli parental strain than in DNA of the isogenic Δpgi strain. To explain this apparent paradox we hypothesized that PGI might be implicated in repair of G6Ph-derived lesions in DNA. In favor of our hypothesis, we further demonstrate that protein extract from the E. coli PGI proficient strain but not from the PGI deficient strain catalyzes the release of G6Ph from G6Ph-modified single stranded DNA oligonucleotide and from its hybrid duplex with a complementary peptide nucleic acid.展开更多
Nine diploid cultivars of Italian ryegrass （Lolium multiflorum Lain.） from France （Fortyl, Vertyl and Jericho）, Germany （Ligrande）, United Kingdom （Aber Epic and Aber Mario）, Denmark （Cordelia）, Netherlands ...Nine diploid cultivars of Italian ryegrass （Lolium multiflorum Lain.） from France （Fortyl, Vertyl and Jericho）, Germany （Ligrande）, United Kingdom （Aber Epic and Aber Mario）, Denmark （Cordelia）, Netherlands （Alamo） and Poland （Tur） were tested with horizontal gel electrophoresis according to one locus （with four alleles） of the PGI enzyme system. One of them, named P4 is typical for the species, therefore can serve as a good marker for hybrids identification. Each cultivar was characterized by frequencies of different phenotypes. They were highly polymorphic （Pg = 0.58 - 0.78） and showed differences in heterozygosity level. The variability within populations （GST = 0.055） was higher than among populations （DST = 0.032）.展开更多
The parasite Plasmodium falciparum is responsible for the major world scourge malaria, a disease that affects 3.3 billion people worldwide. The development of new drugs is critical because of the diminished effectiven...The parasite Plasmodium falciparum is responsible for the major world scourge malaria, a disease that affects 3.3 billion people worldwide. The development of new drugs is critical because of the diminished effectiveness of current antimalarial agents mainly due to parasitic resistance, side effects and cost. Molecular docking was used to explore structural motifs responsible for the interactions between triose phosphate isomerase (TPI), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and aldolase (ALD) from human and Plasmodium cells with 8 novel sufonylamide derivatives. All the ligands modeled, interact with all three enzymes in the micromolar range. The top ligand (sulfaE) shows a 70-fold increase in selective binding to pfTPI compared to hTPI (dissociation constant-KI of 7.83 μM and 0.177 μM for hTPI and pfTPI respectively), on par with antimalarial drug chloroquine.ALD and GAPDH form complexes with similar binding sites, comprising amino acids of similar chemical properties and polarities. Human TPI and pfTPI bind sulfonamide derivatives using two distinct binding sites and residues. Key residues at the dimer interface of pfTPI (VAL44, SER45, TYR48, GLN64, ASN65, VAL78) form a tight pocket with favorable polar contacts. The affinity with TPI is the most specific, stable, and selective suggesting pfTPI is a candidate for development of antimalarial drugs.展开更多
Establishing a transgenic plant largely relies on a selectable marker gene that can confer antibiotic or herbicide resistance to plant cells.The existence of such selectable marker genes in genetically modified foods ...Establishing a transgenic plant largely relies on a selectable marker gene that can confer antibiotic or herbicide resistance to plant cells.The existence of such selectable marker genes in genetically modified foods has long been criticized.Plant cells generally exhibit too low an activity of phosphomannose isomerase(PMI)to grow with mannose as a sole carbon source.In this study,we characterized PMI from the green microalga Chlorococcum sp.and assessed its feasibility as a selectable marker for plant biotechnology.Chlorococcum sp.PMI(ChlPMI)was shown to be closely related to higher plants but more distant to bacterial counterparts.Overexpression of ChlPMI in tomato induced callus and shoot formation in media containing mannose(6 g/L)and had an average transformation rate of 3.9%.Based on this transformation system,a polycistronic gene cluster containing crtB,HpBHY,CrBKT and SlLCYB(BBBB)was co-expressed in a different tomato cultivar.Six putative transformants were achieved with a transformation rate of 1.4%,which produced significant amounts of astaxanthin due to the expression of the BBBB genes.Taken together,these findings indicate that we have established an additional tool for plant biotechnology that may be suitable for genetically modifying foods safely.展开更多
The phosphomannose isomerase （PMI） gene from Saccharomyces cerevisiae acted as selectable marker and mannose acted as selective agent for the production of transgenic plants of rice （Oryza sativa L.） via Agrobacte...The phosphomannose isomerase （PMI） gene from Saccharomyces cerevisiae acted as selectable marker and mannose acted as selective agent for the production of transgenic plants of rice （Oryza sativa L.） via Agrobacterium-mediated transformation. The concentration of mannose during the selection was stepwise increased, 5 g L-1 mannose combined with 15 g L-1 sucrose and 500 mg L-1 cefotaxime was used in the initial selection stage, then the concentration of mannose was increased to 11 g L-1, the highest transformation rate was 20.0%. The integration of PMI gene was confirmed by PCR, and the result of RT-PCR assay proved that the intron of PMI gene can be excised correctly during RNA splicing. 13- Glucuronidase （GUS） activity analysis confirmed the expression of GUS gene. All those means the PMI gene from yeast can be used as a selectable marker in rice transformation.展开更多
Objective Protein disulfide isomerase A2(PDIA2),a member of the protein disulfide isomerase family,plays a key role in the folding of nascent proteins in the endoplasmic reticulum by forming disulfide bonds,together w...Objective Protein disulfide isomerase A2(PDIA2),a member of the protein disulfide isomerase family,plays a key role in the folding of nascent proteins in the endoplasmic reticulum by forming disulfide bonds,together with enzymes such as thiol isomerase,oxidase,and reductase.This study investigated the clinical significance and potential functions of PDIA2 in glioma.Methods The expression of PDIA2 in gliomas was explored using The Cancer Genome Atlas and Gene Expression Omnibus databases.We analyzed the clinical characteristics of glioma patients and the prognostic and diagnostic value of PDIA2 expression.Kaplan-Meier and Cox regression analyses were used to examine the effect of PDIA2 expression on overall survival,progression-free interval,and disease-specific survival.Furthermore,we performed Gene Set Enrichment Analysis and immune infiltration analysis to investigate the functions of PDIA2.PDIA2 mRNA and protein expression was evaluated in cell lines and glioma tissues.Results PDIA2 was expressed at low levels in glioma patients.Kaplan-Meier survival analysis showed that glioma patients with low PDIA2 levels had a worse prognosis than those with high PDIA2 levels.Receiver operating characteristic curve analysis indicated the diagnostic and prognostic ability of PDIA2(area under the curve=0.918).Pathways associated with PD1,PI3K/AKT,cancer immunotherapy via PD1 blockade,Fceri-mediated NF-kB activation,FOXM1,and DNA repair were enriched in glioma patients with low levels of PDIA2.PDIA2 expression levels were negatively correlated with immune cell infiltrate levels.Conclusion PDIA2 levels are significantly downregulated in glioma.PDIA2 expression may be a potential biomarker for the diagnosis and prognosis of glioma patients.展开更多
文摘[Objective]The aim was to clone TapⅡchalcone isomerases（CHI1 A） from soybean specially and construct expression vector of PNZ8149-CHI1 A,and then transform it into Lactococcus Lactis NICE systers.[Method]Chalcone isomerases（CHI1 A） was cloned by RTPCR method,and it was sequenced after cloning into pMD18-T vectors,and recombined to expression vector PNZ8149-CHI1 A,then it was transformed into Lactococcus Lactis NZ3900[Result]The sequencing results indicated that the cloned fragment of CHI1 A contained 670 nucleotides,and shared a sequence homology of 92% with that from Genbank accession number AF595413（CHI1 A）.CHI1 A was transformed into NICE expression system successfully by identification of PCR and digestion.[Conclusion]The foundation of using the microorganism fermentation method to produce flavonoids was laid by construction of efficient induction expression vector with chalcone isomerases CHI1 A.
基金supported by Science and Technology Innovation Program of Hunan province(2024NK1010,2023NK1010,2023ZJ1080)the National Natural Science Foundation of China(U21A20208).
文摘The chalcone isomerase gene OsCHI,one of the key genes in the flavonoid biosynthesis pathway,plays an important role in rice(Oryza sativa)resistance to abiotic stresses.This study reveals how the chalcone isomerase gene family member OsCHI3 participates in rice responses to drought stress through the regulation of flavonoid biosynthesis.Overexpression of OsCHI3 increased the tolerance of rice to drought stress.In contrast,CRISPR/Cas9-mediated deletion of OsCHI3 reduced the drought tolerance of rice,an effect that is reversed by exogenous ABA treatment.Transcriptomic and physiological biochemical analyses indicated that flavonoids regulated by OsCHI3 not only scavenge reactive oxygen species(ROS)but also increase drought tolerance in rice by stimulating ABA biosynthesis through the regulation of OsNCED1 and OsABA8ox3 expression.These findings demonstrate that OsCHI3 increases drought stress tolerance in rice by activating the antioxidant defense system and the ABA metabolic pathway,providing new clues for drought-resistant rice breeding research.
文摘Creutzfeldt-Jakob disease(CJD)is a rare neurodegenerative disorder characterized by abnormalities in the prion protein(PrP),the most common form of human prion disease.Although Genome-Wide Association Studies(GWAS)have identified numerous risk genes for CJD,the mechanisms underlying these risk loci remain poorly understood.This study aims to elucidate novel genetically prioritized candidate proteins associated with CJD in the human brain through an integrative analytical pipeline.Utilizing datasets from Protein Quantitative Trait Loci(pQTL)(NpQTL1=152,NpQTL2=376),expression QTL(eQTL)(N=452),and the CJD GWAS(NCJD=4110,NControls=13569),we implemented a systematic analytical pipeline.This pipeline included Proteome-Wide Association Study(PWAS),Mendelian randomization(MR),Bayesian colocalization,and Transcriptome-Wide Association Study(TWAS)to identify novel genetically prioritized candidate proteins implicated in CJD pathogenesis within the brain.Through PWAS,we identified that the altered abundance of six brain proteins was significantly associated with CJD.Two genes,STX6 and PDIA4,were established as lead causal genes for CJD,supported by robust evidence(False Discovery Rate<0.05 in MR analysis;PP4/(PP3+PP4)≥0.75 in Bayesian colocalization).Specifically,elevated levels of STX6 and PDIA4 were associated with an increased risk of CJD.Additionally,TWAS demonstrated that STX6 and PDIA4 were associated with CJD at the transcriptional level.
基金supported by the National Natural Science Foundation of China(32202253)the Natural Science Foundation of Anhui Higher Education Institutions,China(KJ2020A0102)the Talent Research Project of Anhui Agricultural University,China(rc342001)。
文摘Rice blast,caused by Magnaporthe oryzae,is a fungal disease that causes devastating damage to rice production worldwide.During infection,pathogens secrete effector proteins that modulate plant immunity.Disulfide bond formation catalyzed by protein disulfide isomerases(PDI)is essential for protein folding and maturation.However,the biological function of Pdi1 in M.oryzae has not yet been characterized.In this study,we identified the endoplasmic reticulum(ER)-located protein,MoPdi1,in M.oryzae.MoPdi1 regulates conidiation,cell wall stress,and pathogenicity of M.oryzae.Furthermore,the CGHC active sites in the a and a'redox domain of MoPdi1 were essential for the biological function of MoPDI1.Further tests demonstrated that MoPdi1 was involved in the regulation of ER stress and positively regulated ER phagy.We also found that MoPdi1 interacted with MoHut1.Deletion of MoPDI1 led to the bereft of MoHut1 dimerization,which depends on the formation of disulfide bonds.In addition,MoPdi1 affected the normal secretion of the cytoplasmic effector AVR-Pia.We provided evidence that MoHut1 is important for the vegetative growth,conidiation,and pathogenicity in M.oryzae.Therefore,our findings could provide a suitable target point for designing antifungal agrochemicals against rice blast fungus.
文摘pdi gene from Medicago sativa L. ,encoding Protein Disulfide Isomerase（ mPDI ）, has been cloned and sequenced. According to the mRNA and amino acid sequence, the character of mPDI such as the physical and chemical properties, hydrophilicity/hydrophobicity, signal peptide, secondary structure, coiled coil, transmembrane domains, O-glycogylation site, active site, subcellular localization, functional structural domains and three-dimensional structure were analyzed by a series of bioinformatics software. The results showed that mPDI was a hydrophobic and stable protein with 3 coiled coils, 30-glycogylation sites, 2 structural domains of thioredoxin, 2 active sites of thioredoxin, and located in rough endoplasmic reticulum. It has 512 amino acids, the theoretical pl is 4.98, and signal peptide located in 1-24AA. In the secondary structure, a-helix, random coil, extended chain is 26.37%, 53.32%, 20.31% respectively. The validation of modeling accords with the stereochemistry.
基金supported by the National Natural Science Foundation in China (NO. 30671126 40706050 and 40706048)+3 种基金National Key Technology R&D Program (No. 11200602)The Special Foundation of State-level and Public Interest Research Institute (No. 2060402/2)Natural Science Foundation in Shandong University of Technology (No. 4040306017) Start-up Foundation for Ph.D in Shandong University of Technology (No. 4041-405017 and 4041-405016)
文摘The unicellular green alga Haematococcus pluvia/is uniquely accumulates carotenoids in the cytoplasm and in late developmental stages turns deep-red in color because of accumulation of astaxanthin in the cytosol. The enzyme, isopentenyl pyrophosphate （IPP） isomerase, plays a key role in astaxanthin biosynthesis of H. pluvialis. In this paper, two separate 5＇-flanking regions （1.8 kb and 2.5 kb） of IPP isomerase gene was cloned through walking upstream firstly. Results of sequence analysis =showed that two separate 5＇-flanking regions of IPP isomerase gene might have similar putative cis-acting elements such as ABA （abscisic acid）-responsive element （ABRE）, drought-responsive element （DRE/C-repeat）, light-responsive element （G-box, GAG-motif, I-box and ATC-motif）, heat-shock element （HSE）, wound-responsive element （WUN-motif）, SA （salicylic acid）-responsive element （TCA-element）, auxin-responsive element （TGA-element）, MeJA （methyl jasmonate）-responsive element （TGACG-element）, enhancer-like element involved in anoxic specific inducibility （GC-motif） and MYB binding sites （MBS and MRE）, except for typical TATA box or CCAAT box, which exhibit diversiform transcriptional patterns of IPP isomerase gene in astaxanthin biosynthesis of Haematococcus pluvialis.
基金Supported by Science and Technology Planning Project of Mudanjiang(G2015d1974)Funding Project of Training of Famous Teachers in Mudanjiang Normal University(2014QNGG1805)~~
文摘This study analyzed and predicted following aspects of isopentenyl py- rophosphate isomerases （IPIs） of five north medicinal plants using bioinformatics methods and tools： physical and chemical properties, hydrophobicity/hydrophilicity, trans-membrane domain, secondary structure, subcellular localization and so on. The results showed that： there was no notable difference among the physical and chem- ical properties of IPIs of the five north medicinal plants; the IPIs were mainly hy- drophilic; the IPIs were mainly located in chloroplasts by subcellular localization; serine phosphorylation sites were the most; the secondary structures mainly consist- ed of c^-helixes and random coils; no signal peptide existed, indicating that the pro- tein IPI was non-secreted protein; no trans-membrane domain existed; and one functional domain was shown, Le., Nudix Hydrolase Superfamily. This study is of great significance to research on IPI gene functions, deep research on north medic- inal plants, improvement of efficacy of north medicinal plants and rational develop- ment and utilization of medicinal plant resources.
基金Supported by Scientific Research Fund of Changzhi University (2010111)~~
文摘[Objective] The aim was to clone triosephosphate isomerase （TPI） gene from Apis mellifera, and predict the properties of TPI protein with bioinformatic meth- ods. [Method] The TPI gene was firstly cloned by in silico cloning based on the ex- pressed sequence tags （ESTs） from Unigene of NCBI. Some characters of the TPI protein including hydrophobicity or hydrophilicity, isoelectric point （pl） and secondary structure were analyzed and predicted by the tools of bioinformatics. [Result] The TPI gene from A. mellifera was 1 768 bp in full length and it contained a complete ORF which encoded 247 amino acids; the pl of TPI protein was 8.515; the TPI protein was a member of ~13-fold family. [Conclusion] The in silico cloning based on the expressed sequence tags is a efficient method in practice, and this study will provide more references for further study on A. mellifera at molecular level.
基金supported in part by the Natural Science Foundation of Beijing, China (5121001)the Cultivate New Varieties of Genetically Modified Organisms Technology Major Projects, the Ministry of Science and Technology of China (2009ZX08012-006B)
文摘Phosphomannose isomerase （PMI） encoding gene manA is a desirable selective marker in transgenic research. Under- standing of its expression patterns in transgenic plant and establishing highly sensitive detection method based on immunoassay have great impacts on the application of PMI. In this study, PMI-specific monoclonal antibodies were generated using recombinant protein as immunogen, and could be used in Western blot to detect as little as 0.5 ng His-tagged PMI protein or rice expressed PMI protein in sample accounted for 0.4% of single rice grain （about 0.08 mg）. PMI protein driven by CaMV-35S promoter was detected in dozens of tested tissues, including root, stem, leaf, panicle, and seed at all developmental stages during rice growing, and PMI protein accounted for about 0.036% of total protein in the leaves at seedling stage. The established method potentially can be used to monitor PMI protein in rice grains.
基金supported by grants from the National Natural Science Foundation of China(No.82072813)Natural Science Foundation of Guangdong Province(No.2020A1515010473 and No.2018A030313668)China Postdoctoral Science Foundation(No.2020M682666).
文摘The limited treatment options for advanced prostate cancer(PCa)lead to the urgent need to discover new anticancer drugs.Mannose,an isomer of glucose,has been reported to have an anticancer effect on various tumors.However,the anticancer effect of mannose in PCa remains unclear.In this study,we demonstrated that mannose inhibits the proliferation and promotes the apoptosis of PCa cells in vitro,and mannose was observed to have an anticancer effect in mice without harming their health.Accumulation of intracellular mannose simultaneously decreased the mitochondrial membrane potential,increased mitochondrial and cellular reactive oxygen species(ROS)levels,and reduced adenosine triphosphate(ATP)production in PCa cells.Mannose treatment of PCa cells induced changes in mitochondrial morphology,caused dysregulated expression of the fission protein,such as fission,mitochondrial 1(FIS1),and enhanced the expression of proapoptotic factors,such as BCL2-associated X(Bax)and BCL2-antagonist/killer 1(Bak).Furthermore,lower expression of mannose phosphate isomerase(MPI),the key enzyme in mannose metabolism,indicated poorer prognosis in PCa patients,and downregulation of MPI expression in PCa cells enhanced the anticancer effect of mannose.This study reveals the anticancer effect of mannose in PCa and its clinical significance in PCa patients.
基金supported by the National Natural Science Foundation of China, No. 30872609
文摘Spinal cord ischemia/reperfusion injury is a stress injury to the spinal cord. Our previous studies using differential proteomics identified 21 differentially expressed proteins （n 〉 2） in rabbits with spinal cord ischemia/reperfusion injury. Of these proteins, stress-related proteins included protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70. In this study, we established New Zealand rabbit models of spinal cord ischemia/reperfusion injury by abdominal aorta occlusion. Results demonstrated that hind limb function initially improved after spinal cord ischemia/reperfusion injury, but then deteriorated. The pathological morphology of the spinal cord became aggravated, but lessened 24 hours after reperfusion. However, the numbers of motor neurons and interneurons in the spinal cord gradually decreased. The expression of protein disulfide isomerase A3, stress-induced-phosphoprotein 1 and heat shock cognate protein 70 was induced by ischemia/reperfusion injury. The expression of these proteins increased within 12 hours after reperfusion, and then decreased, reached a minimum at 24 hours, but subsequently increased again to similar levels seen at 6-12 hours, showing a characterization of induction-inhibition-induc- tion. These three proteins were expressed only in cytoplasm but not in the nuclei. Moreover, the expression was higher in interneurons than in motor neurons, and the survival rate of interneurons was greater than that of motor neurons. It is assumed that the expression of stress-related proteins exhibited a protective effect on neurons.
基金supported by grants from the Ministry of Science and Technology of the People’s Republic of China (No. SS2014AA020603)Beijing Municipal Administration of Hospitals Clinical Medicine Development of Special Funding Support (No. ZYLX201701)+3 种基金Beijing Municipal Science and Technology Commission (No. D1311 00005313010)the National Natural Science Foundation of China (No. 31520103905)the National High Technology Research and Development Program (“863” Program) of China (No. 2015AA020108)the Zhi-Yuan chair professorship start-up grant WF220103010 from Shanghai Jiao Tong University
文摘Objective: Tumor heterogeneity renders identification of suitable biomarkers of gastric cancer(GC)challenging. Here, we aimed to identify prognostic genes of GC using computational analysis.Methods: We first used microarray technology to profile gene expression of GC and paired nontumor tissues from 198 patients. Based on these profiles and patients’ clinical information, we next identified prognostic genes using novel computational approaches. Phosphoglucose isomerase, also known as glucose-6-phosphate isomerase(GPI), which ranked first among 27 candidate genes, was further investigated by a new analytical tool namely enviro-geno-pheno-state(E-GPS) analysis. Suitability of GPI as a prognostic marker, and its relationship with physiological processes such as metabolism, epithelial-mesenchymal transition(EMT), as well as drug sensitivity were evaluated using both our own and independent public datasets.Results: We found that higher expression of GPI in GC correlated with prolonged survival of patients.Particularly, a combination of CDH2 and GPI expression effectively stratified the outcomes of patients with TNM stage Ⅱ/Ⅲ. Down-regulation of GPI in tumor tissues correlated well with depressed glucose metabolism and fatty acid synthesis, as well as enhanced fatty acid oxidation and creatine metabolism, indicating that GPI represents a suitable marker for increased probability of EMT in GC cells.Conclusions: Our findings strongly suggest that GPI acts as a novel biomarker candidate for GC prognosis,allowing greatly enhanced clinical management of GC patients. The potential metabolic rewiring correlated with GPI also provides new insights into studying the relationship between cancer metabolism and patient survival.
基金This work was supported by the National Natural Science Foundation of China （No.20336010） and the State Key Basic Research and Development Plan of China （No.2003CB716000）.
文摘The complex model of Thermus thermophilus xylose isomerase （TtXI） with D-xylose was constructed, and molecular dynamics （MD） simulations were carried out at 300 and 360 K for 10 ns by NAMD2.5. The radius of gyration （Rg）, subunit interactions, and residue flexibility were analyzed. The results show that residues 60-69, 142-148, 169-172, and 332-340 have high flexibility at 300 and 360 K. Residues with higher flexibility at 360 K than that at 300 K can mainly be divided into two groups： one locates in the helix-loophelix region consisting of residues 55-80 in catalytic domain; the other at subunit interfaces. The Rg of catalytic domain at 360 K shows 0.16 A higher than that at 300 K, but Rg of small C-terminal domain has no obvious difference. The results indicate that enhanced Rg of catalytic domain may lead to the intense motion of the active site of TtXI and promote the D-xylose isomization reaction. Eight hydrogen bonds and five ion pairs are reduced at subunit interfaces at 360 K compared with 300 K, that may be the main reason for the decrease in rigidity and increase in activity at high temperature of TtXI. This result also help to explain the cold-adaption phenomenon of TtXI E372G mutant reported previously. Our results reveal the relationship between temperature and structure flexibility of TtXI, and play an important role in understanding the thermostability of thermophile protein with multiple subunits.
文摘L-arabinose isomerase (L-AI) is the key enzyme for D-galactose isomerization of D-tagatose by biological method. In this research, Lactobacillus plantarum WU14 with high D-tagatose yield was identified as Lactobacillus plantarum was isolated from the number of lactic acid bacteria from pickled vegetables. The crude L-arabinose isomerase activity of Lactobacillus plantarum WU14 with high D-tagatose yield was 13.95 U/mL under the optimal temperature 60°C, pH 7.17 and substrate concentration 0.8 mol/L, and the conversion rate of 56.12% could be gained after 28 hours. Protein structure and specific of L-Arabinose Isomerase of Lactobacillus plantarum WU14 were researched. The results showed that L-arabinose isomerase is mainly composed of alpha helix and random coil. Then the recombinant L-AI gene was inserted into the food-grade expression vector pRNA48 and expressed in L. lactis NZ9000 successfully. The target protein expression reached the maximum amount when the induced concentration of nisin reaches 30 ng/mL after 12 h. And the crude enzyme activity of recombinant bacteria reached 6.21 U/mL under 60°C. Otherwise the optimal conversion rate recombinant of L. lactis NZ9000/pRNA48-L-AI can reach 39.21% under the temperature of 50°C, pH 7.17 and D-galactose concentration was 0.6 mol/L.
文摘Phosphoglucose isomerase (PGI) is a key enzyme in early glycolysis, which catalyzes the reversible isomerization of glucose 6-phosphate (G6Ph) to fructose 6-phosphate. We have constructed an Escherichia coli K12 strain with a deleted pgi gene (Δpgi) and shown that this strain in comparison with the parental strain 1) accumulates higher amount of G6Ph, 2) grows slowly, and 3) exhibits higher spontaneous mutation frequency to rifampicin resistance (Rifr), when grown on high glucose minimal medium. Intriguingly, the spontaneous mutation rate to Rifr was inversely related to the degree of E. coli chromosomal DNA modification with sugar derivatives. We measured higher concentrations of Amadori products, fluorophores (360 nm excitation/440 nm emission) and carboxymethyl residues in the chromosomal DNA of the E. coli parental strain than in DNA of the isogenic Δpgi strain. To explain this apparent paradox we hypothesized that PGI might be implicated in repair of G6Ph-derived lesions in DNA. In favor of our hypothesis, we further demonstrate that protein extract from the E. coli PGI proficient strain but not from the PGI deficient strain catalyzes the release of G6Ph from G6Ph-modified single stranded DNA oligonucleotide and from its hybrid duplex with a complementary peptide nucleic acid.
文摘Nine diploid cultivars of Italian ryegrass （Lolium multiflorum Lain.） from France （Fortyl, Vertyl and Jericho）, Germany （Ligrande）, United Kingdom （Aber Epic and Aber Mario）, Denmark （Cordelia）, Netherlands （Alamo） and Poland （Tur） were tested with horizontal gel electrophoresis according to one locus （with four alleles） of the PGI enzyme system. One of them, named P4 is typical for the species, therefore can serve as a good marker for hybrids identification. Each cultivar was characterized by frequencies of different phenotypes. They were highly polymorphic （Pg = 0.58 - 0.78） and showed differences in heterozygosity level. The variability within populations （GST = 0.055） was higher than among populations （DST = 0.032）.
文摘The parasite Plasmodium falciparum is responsible for the major world scourge malaria, a disease that affects 3.3 billion people worldwide. The development of new drugs is critical because of the diminished effectiveness of current antimalarial agents mainly due to parasitic resistance, side effects and cost. Molecular docking was used to explore structural motifs responsible for the interactions between triose phosphate isomerase (TPI), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and aldolase (ALD) from human and Plasmodium cells with 8 novel sufonylamide derivatives. All the ligands modeled, interact with all three enzymes in the micromolar range. The top ligand (sulfaE) shows a 70-fold increase in selective binding to pfTPI compared to hTPI (dissociation constant-KI of 7.83 μM and 0.177 μM for hTPI and pfTPI respectively), on par with antimalarial drug chloroquine.ALD and GAPDH form complexes with similar binding sites, comprising amino acids of similar chemical properties and polarities. Human TPI and pfTPI bind sulfonamide derivatives using two distinct binding sites and residues. Key residues at the dimer interface of pfTPI (VAL44, SER45, TYR48, GLN64, ASN65, VAL78) form a tight pocket with favorable polar contacts. The affinity with TPI is the most specific, stable, and selective suggesting pfTPI is a candidate for development of antimalarial drugs.
基金supported by a grant from Yunnan high talents program(Y33D331),Yunnan Province,China.
文摘Establishing a transgenic plant largely relies on a selectable marker gene that can confer antibiotic or herbicide resistance to plant cells.The existence of such selectable marker genes in genetically modified foods has long been criticized.Plant cells generally exhibit too low an activity of phosphomannose isomerase(PMI)to grow with mannose as a sole carbon source.In this study,we characterized PMI from the green microalga Chlorococcum sp.and assessed its feasibility as a selectable marker for plant biotechnology.Chlorococcum sp.PMI(ChlPMI)was shown to be closely related to higher plants but more distant to bacterial counterparts.Overexpression of ChlPMI in tomato induced callus and shoot formation in media containing mannose(6 g/L)and had an average transformation rate of 3.9%.Based on this transformation system,a polycistronic gene cluster containing crtB,HpBHY,CrBKT and SlLCYB(BBBB)was co-expressed in a different tomato cultivar.Six putative transformants were achieved with a transformation rate of 1.4%,which produced significant amounts of astaxanthin due to the expression of the BBBB genes.Taken together,these findings indicate that we have established an additional tool for plant biotechnology that may be suitable for genetically modifying foods safely.
基金the Genetically Modified Organisms Breeding Major Projects, China (2011ZX08003-003)
文摘The phosphomannose isomerase （PMI） gene from Saccharomyces cerevisiae acted as selectable marker and mannose acted as selective agent for the production of transgenic plants of rice （Oryza sativa L.） via Agrobacterium-mediated transformation. The concentration of mannose during the selection was stepwise increased, 5 g L-1 mannose combined with 15 g L-1 sucrose and 500 mg L-1 cefotaxime was used in the initial selection stage, then the concentration of mannose was increased to 11 g L-1, the highest transformation rate was 20.0%. The integration of PMI gene was confirmed by PCR, and the result of RT-PCR assay proved that the intron of PMI gene can be excised correctly during RNA splicing. 13- Glucuronidase （GUS） activity analysis confirmed the expression of GUS gene. All those means the PMI gene from yeast can be used as a selectable marker in rice transformation.
基金the Natural Science Foundation of Southwest Medical University(No.2016XNYD217,No.2018-ZRQN-032 and No.2016LZXNYD-G03)the National Natural Science Foundation of China(No.82072780)Sichuan Science and Technology Program(No.2022YFS0630).
文摘Objective Protein disulfide isomerase A2(PDIA2),a member of the protein disulfide isomerase family,plays a key role in the folding of nascent proteins in the endoplasmic reticulum by forming disulfide bonds,together with enzymes such as thiol isomerase,oxidase,and reductase.This study investigated the clinical significance and potential functions of PDIA2 in glioma.Methods The expression of PDIA2 in gliomas was explored using The Cancer Genome Atlas and Gene Expression Omnibus databases.We analyzed the clinical characteristics of glioma patients and the prognostic and diagnostic value of PDIA2 expression.Kaplan-Meier and Cox regression analyses were used to examine the effect of PDIA2 expression on overall survival,progression-free interval,and disease-specific survival.Furthermore,we performed Gene Set Enrichment Analysis and immune infiltration analysis to investigate the functions of PDIA2.PDIA2 mRNA and protein expression was evaluated in cell lines and glioma tissues.Results PDIA2 was expressed at low levels in glioma patients.Kaplan-Meier survival analysis showed that glioma patients with low PDIA2 levels had a worse prognosis than those with high PDIA2 levels.Receiver operating characteristic curve analysis indicated the diagnostic and prognostic ability of PDIA2(area under the curve=0.918).Pathways associated with PD1,PI3K/AKT,cancer immunotherapy via PD1 blockade,Fceri-mediated NF-kB activation,FOXM1,and DNA repair were enriched in glioma patients with low levels of PDIA2.PDIA2 expression levels were negatively correlated with immune cell infiltrate levels.Conclusion PDIA2 levels are significantly downregulated in glioma.PDIA2 expression may be a potential biomarker for the diagnosis and prognosis of glioma patients.
