Autophagy is well-known for delivering cargo materials to lysosomes for proteolytic digestion.Recently,autophagy has emerged as a key mechanism in unconventional protein secretion(UPS).This perspective introduces unco...Autophagy is well-known for delivering cargo materials to lysosomes for proteolytic digestion.Recently,autophagy has emerged as a key mechanism in unconventional protein secretion(UPS).This perspective introduces unconventional secretion pathways,focusing on secretory autophagy and its role in secreting protein aggregates associated with neurodegenerative disorders.We also explore additional neuronal functions of secretory autophagy beyond the release of protein aggregates.We propose autophagosomes as transport organelles that deliver cargo material directly from the endoplasmatic reticulum(ER)to the plasma membrane rather than solely to lysosomes.展开更多
The soil-resident pathogen, Plasmodiophora brassicae, infects cruciferous crops, causing obligate parasitic clubroot disease and posing a significant threat to the Brassica vegetable industry in China. To learn more a...The soil-resident pathogen, Plasmodiophora brassicae, infects cruciferous crops, causing obligate parasitic clubroot disease and posing a significant threat to the Brassica vegetable industry in China. To learn more about its pathogenesis, we reported a Nanopore sequencing-derived25.3 Mb high-quality genome sequence of P. brassicae pathotype 4 strain(P.b 4). Comparing the P.b 4 genome with that of the published P.brassicae e3 genome(P.b e3) identified single nucleotide polymorphisms, structural variations, and small insertions and deletions. We then carried out RNA-sequencing of root samples from a clubroot-susceptible line at 5, 14, and 28 days after inoculation(DAI), and classified genes into five categories based on their expression patterns. Interestingly, 158 genes were highly expressed at 14 DAI, which were enriched in budding cell isotropic bud growth, ascospore wall assembly, spore wall assembly, spore wall biogenesis, and ascospore wall biogenesis.Subsequently, we bioinformatically predicted 555 secreted effector candidates, among which only 125 were expressed during infection and had amino acid lengths less than 400. The putative effector Pb010018, which was highly expressed at 14 DAI, was validated to have a signal peptide using a yeast secretion system. Luciferase activity and co-immunoprecipitation assays demonstrated that Pb010018 interacts with serine hydroxymethyltransferase BrSHMT1, and expression analysis showed that SHMT1 was upregulated in both Arabidopsis and B. rapa during infection. Furthermore, after infection, the Arabidopsis shmt1 mutant(atshmt1) showed reduced severity of clubroot disease, together with downregulated expression of Pb010018. Our results offer new insights into plant-pathogen interaction mechanisms, and provide the possibility for improving Brassica resistance to clubroot disease.展开更多
BACKGROUND Pancreatic cancer tissues mainly consist of fibrotic and dense stroma,which limits their therapeutic efficacy.The stromal fibroblasts of pancreatic tumors frequently express the secreted protein acidic and ...BACKGROUND Pancreatic cancer tissues mainly consist of fibrotic and dense stroma,which limits their therapeutic efficacy.The stromal fibroblasts of pancreatic tumors frequently express the secreted protein acidic and rich in cysteine(SPARC).AIM To assess the impact of SPARC and its oncological relevance in patients undergoing pancreatic cancer resection.METHODS Ninety-one pancreatic ductal adenocarcinoma specimens were obtained from patients with curative resection between January 2009 and December 2015 as a retrospective study.SPARC expression patterns were analyzed using immunohistochemistry.Oncological outcomes were analyzed based on SPARC expression patterns.Oncological outcomes,based on SPARC expression,were analyzed in The Cancer Genome Atlas-Pancreatic Adenocarcinoma cohort(retrieved from a public database).RESULTS Patients with stromal SPARC expression(sSPARC+)had poorer overall survival than that in those without it(sSPARC-)(P=0.035).However,among patients who received adjuvant treatment,no difference was observed in survival between the sSPARC+and the sSPARC-groups(P=0.14).In The Cancer Genome Atlas-Pancreatic Adenocarcinoma samples,the high SPARC expression group exhibited noticeably lower overall survival than that in the low expression group(cutoff:14.1295,P=0.0222).Furthermore,SPARC expression was strongly correlated with the percentage the CD10+stromal component(R2=0.804,P<0.001).CONCLUSION Adjuvant chemotherapy improves survivals in sSPARC+pancreatic cancer patients,indicating suggesting sSPARC expression as a prognostic biomarker and potential indicator for neoadjuvant treatment planning.展开更多
Fungal pathogens utilize intricate signaling networks to regulate growth,morphogenesis,and infection processes,enabling them to adapt to environmental cues and successfully colonize their hosts.Among these networks,th...Fungal pathogens utilize intricate signaling networks to regulate growth,morphogenesis,and infection processes,enabling them to adapt to environmental cues and successfully colonize their hosts.Among these networks,the Ras signaling pathway has been extensively studied for its role in fungal morphogenesis and virulence.However,the specific contributions of Ras2 to key pathogenesis processes,such as cytoskeletal organization,appressorium formation,and protein secretion,remain poorly understood.Addressing this gap is critical to understanding the molecular mechanisms underlying fungal virulence and identifying potential targets for disease control strategies.Here,a Ras2 homologue(Cgras2)was identified in Colletotrichum gloeosporioides,a hemibiotrophic fungal pathogen responsible for anthracnose diseases in over 3200 plant species.Using a target deletion mutantΔCgras2,we found that Cgras2 is essential for maintaining conidial germination polarity,cell division,and virulence.Knockout of Cgras2 also impaired appressorium formation and infection by disrupting cytoskeletal networks,including F-actin and septin rings,and by reducing turgor pressure,which is critical for penetration peg formation.Additionally,Cgras2 functions as an upstream regulator of the cAMP signaling pathway,asΔCgras2 mutants exhibit reduced intracellular cAMP levels.Supplementation with exogenous cAMP partially rescued the formation of appressoria and the virulence inΔCgras2 mutant,confirming the regulatory role of Cgras2 in cAMP signaling.RNA-seq analysis further revealed significant downregulation of membrane transporter-encoding genes inΔCgras2 mutants,leading to disruptions in sugar and ion uptake.Secretome analysis demonstrated that Cgras2 also controls extracellular secretion of plant cell wall-degrading enzymes and other virulence factors by regulating the secretion process and genes involved in transcription.Enzymatic activity assays of extracellular hydrolases further confirmed that the absence of Cgras2 significantly impaired secretory capacity.Our findings establish the Cgras2 protein as a central regulator of fungal infection strategies by linking cytoskeletal organization,membrane transport,and protein secretion with Ras2 signaling.These insights provide a foundation for future research into Ras2-mediated signaling networks and identify Cgras2 as a promising target for controlling fungal diseases in plants.展开更多
AIM： To investigate the functions of promoter hypermethylation of secreted frizzled-related proteins （sFRPs） genes in colorectal tumorigenesis and progression. METHODS： The promoter hypermethylation and expression...AIM： To investigate the functions of promoter hypermethylation of secreted frizzled-related proteins （sFRPs） genes in colorectal tumorigenesis and progression. METHODS： The promoter hypermethylation and expression of sFRP genes in 72 sporadic colorectal carcinomas, 33 adenomas, 18 aberrant crypt foci （ACF） and colorectal cancer cell lines RKO, HCT116 and SW480 were detected by methylation-specific PCR and reverse transcription PCR, respectively. RESULTS： None of the normal colorectal mucosa tissues showed methylated bands of any of four sFRP genes, sFRP1, 2, 4 and 5 were frequently methylated in colorectal carcinoma, adenoma and ACF （sFRP1 〉 85%, sFRP2 〉75%, sFRP5 〉 50%）, and the differences between three colorectal tissues were not significant （P 〉 0.05）. IVlethylation in colorectal tumors was more frequent than in normal mucosa and adjacent normal mucosa. The mRNA of sFRP1-5 genes was expressed in all normal colorectal mucosa samples. Expression of sFRP1, 2, 4 and 5 and sFRP1, 2 and 5 was downregulated in carcinoma and adenoma, respectively. The downregulation of sFRP2, 4 and 5 was more frequent in carcinoma than in adenoma. Expression of sFRP3 which promoter has no CpG island was downregulated in only a few of colorectal tumor samples （7/105）. The downregulation ofsFRP1, 2, 4 and 5 expression was significantly associated with promoter hypermethylation in colorectal tumor. After cells were treated by DAC/TSA combination, the silenced sFRP mRNA expression could be effectively re-expressed in colorectal cancer cell lines. CONCLUSION： Hypermethylation of sFRP genes is a common early event in the evolution of colorectal tumor, occurring frequently in ACF, which is regarded as the earliest lesion of multistage colorectal carcinogenesis. It appears to functionally silence sFRP genes expression. Methylation of sFRP1, 2 and 5 genes might serve as indicators for colorectal tumor.展开更多
AIM： To identify the methylation of secreted frizzled-related protein 1 （SFRP1） in gastric cancer and to investigate the aberrant expression of SFRP1 and its correlation with the clinical pathological features of p...AIM： To identify the methylation of secreted frizzled-related protein 1 （SFRP1） in gastric cancer and to investigate the aberrant expression of SFRP1 and its correlation with the clinical pathological features of patients. METHODS： We determined SFRP1 methylation and SFRP1 mRNA expression in 3 gastric cancer cell lines SGC-7901, BGC-823, HGC-27, from 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens by methylation-specific （MSP） PCR and RT-PCR respectively. Fisher＇s exact test was used to analyze the statistical association between clinical pathological data and aberrant expression of SFRP1. RESULTS： In 3 cancer cell lines, BGC-823 and HGC-27 had methylated SFRP1 and lost SFRP1 mRNA expression. After treatment of BGC-823 and HGC-27 with the demethylating agent, 5-aza-2′-deoxycytidine, SFRP1 was re-expressed. In 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens, hypermethylation of SFRP1 was detected in 23 （44%） and 8 （15%） specimens respectively （x^2= 10.34, P 〈 0.01）. Loss of SFRP1 expression was detected in 17（33%） and 6 （12%） specimens respectively （x^2= 6.75, P 〈 0.01）. There was a significant correlation between SFRP1 hypermethylation and SFRP1 expression loss. SFRP1 expression was also correlated significantly with tumor stage and lymph node status, but not with patient sex, age and histological type. CONCLUSION： SFRP1 inactivation is a common and early event caused mainly by hypermethylation in gastric cancer. SFRP1 expression loss may be correlated with tumor metastasis in primary gastric cancer.展开更多
Computer based software such as the SignalP v3.0, TargetP v1.01, big-PI predictor and TMHMM v2.0 were combined to predict the signal peptides, and the signal peptide-dependent secreted proteins among the 6 700 ORFs in...Computer based software such as the SignalP v3.0, TargetP v1.01, big-PI predictor and TMHMM v2.0 were combined to predict the signal peptides, and the signal peptide-dependent secreted proteins among the 6 700 ORFs in genome of Saccharomyces cerevisiae. The results showed that 163 proteins were the secreted ones containing signal peptides, and they were secreted via Sec pathway. Among the 163 predicted secreted proteins, the signal peptides of 47 secreted proteins included only the H-domain and C-domain, without N-domain, but the signal peptides of other 116 secreted proteins included all the three domains. There were differences in the constitution of signal peptides between the secreted proteins of S. cerevisiae and of Candida albicans, but the length and amino acids types of their signal peptides were similar in general. Few of the same signal peptides occurred in the secreted proteins of S. cerevisiae genome, and the homology could be compared among the secreted proteins with the same signal peptides. The BLAST 2 SEQUENECES and CLUSTAL W were used to align the two protein sequences and multi-protein sequences, respectively. The alignment result indicated that homology of these sequences with the same signal peptide was very highly conservative in amino acid of complete gene. The effect of the signal peptides in S. cerevisia on expression of foreign eukaryotic secreted proteins is discussed in this paper.展开更多
The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation ...The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation of these genes remain largely unknown.Here,through comparative transcriptome and chromatin immunoprecipitation sequencing(ChIP-seq)analyses of the methyltransferase PoKmt6 in rice blast fungus Pyricularia oryzae(syn.Magnaporthe oryzae),we found that PoKmt6-mediated H3K27me3 deposition was enriched mainly at fast-evolving regions and contributed to the silencing of a subset of secreted proteins(SP)and transposable element(TE)families during the vegetative growth of P.oryzae.Intriguingly,we observed that a group of SP genes,which were depleted of H3K27me3 modification,could also be silenced via the H3K27me3-mediated repression of the nearby TEs.In conclusion,our results indicate that H3K27me3 modification mediated by PoKmt6 regulates the expression of some SP genes in fast-evolving regions through the suppression of nearby TEs.展开更多
BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its ab...BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its aberrant methylation in gastric cancer(GC)is still inadequate.In the present research,we performed fundamental research to clarify the precise function of methylation on SPARC and its significance in GC.AIM To investigate promoter methylation and the effects of the SPARC gene in GC cells and tissues and to evaluate its clinical significance.METHODS Plasmids that overexpressed the SPARC gene were transfected into human GC BGC-823 cells;non-transfected cells were used as a control group(NC group).Quantitative real-time polymerase chain reaction and western blotting(WB)were then used to detect the expression of SPARC.Methylation-specific polymerase chain reaction was executed to analyze the gene promoter methylation status.Cell viability was measured by the cell counting kit-8 assay.The migration and invasion ability of cells were detected by scratch assays and transwell chamber assays,respectively.Cell cycle events and apoptosis were observed with a flow cytometer.RESULTS The expression of SPARC mRNA in GC tissues and cells was significantly lower and showed differing degrees of hypermethylation,respectively,than that in normal adjacent tissues and control cells.Treatment with 5-Aza-2’-deoxycytidine(5-Aza-Cdr)was able to restore the expression of SPARC and reverse promoter hypermethylation.Overexpression of the SPARC gene significantly inhibited proliferation,migration,and invasion of GC cells,while also causing cell cycle arrest and apoptosis;the NC group exhibited the opposite effects.CONCLUSION This study demonstrated that SPARC could function as a tumor suppressor and might be silenced by promoter hypermethylation.Furthermore,in GC cells,SPARC inhibited migration,invasion,and proliferation,caused cell cycle arrest at the G0/G1 phase,and promoted apoptosis.展开更多
Objective Microcystin-leucine-arginine(MC-LR)exposure induces lipid metabolism disorders in the liver.Secreted frizzled-related protein 5(SFRP5)is a natural antagonist of winglesstype MMTV integration site family,memb...Objective Microcystin-leucine-arginine(MC-LR)exposure induces lipid metabolism disorders in the liver.Secreted frizzled-related protein 5(SFRP5)is a natural antagonist of winglesstype MMTV integration site family,member 5A(Wnt5a)and an anti-inflammatory adipocytokine.In this study,we aimed to investigate whether MC-LR can induce lipid metabolism disorders in hepatocytes and whether SFRP5,which has anti-inflammatory effects,can alleviate the effects of hepatic lipid metabolism by inhibiting the Wnt5a/Jun N-terminal kinase(JNK)pathway.Methods We exposed mice to MC-LR in vivo to induce liver lipid metabolism disorders.Subsequently,mouse hepatocytes that overexpressed SFRP5 or did not express SFRP5 were exposed to MC-LR,and the effects of SFRP5 overexpression on inflammation and Wnt5a/JNK activation by MC-LR were observed.Results MC-LR exposure induced liver lipid metabolism disorders in mice and significantly decreased SFRP5 mRNA and protein levels in a concentration-dependent manner.SFRP5 overexpression in AML12cells suppressed MC-LR-induced inflammation.Overexpression of SFRP5 also inhibited Wnt5a and phosphorylation of JNK.Conclusion MC-LR can induce lipid metabolism disorders in mice,and SFRP5 can attenuate lipid metabolism disorders in the mouse liver by inhibiting Wnt5a/JNK signaling.展开更多
Fusarium graminearum,the primary pathogenic fungus responsible for Fusarium head blight(FHB)in wheat,secretes abundant chemical compounds that interact with host plants.In this study,a secreted protein FgHrip1,isolate...Fusarium graminearum,the primary pathogenic fungus responsible for Fusarium head blight(FHB)in wheat,secretes abundant chemical compounds that interact with host plants.In this study,a secreted protein FgHrip1,isolated from the culture filtrate of F.graminearum,was found to induce typical cell death in tobacco.The FgHrip1 gene was then cloned and expressed in Escherichia coli.Further bioassay analysis showed that the recombinant FgHrip1 induced early defense induction events,such as reactive oxygen species(ROS)production,callose deposition,and up-regulation of defense-related genes in tobacco.Furthermore,FgHrip1 significantly enhanced immunity in tobacco seedlings against Pseudomonas syringae pv.tabaci 6605(Pst.6605)and tobacco mosaic virus(TMV).FgHrip1-treated wheat spikes also exhibited defense-related transcript accumulation and developed immunity against FHB infection.Whereas the expression of FgHrip1 was induced during the infection process,the deletion of the gene impaired the virulence of F.graminearum.Our results suggest that FgHrip1triggers immunity and induces disease resistance in tobacco and wheat,thereby providing new insight into strategy for biocontrol of FHB.展开更多
The structure similarity of secreted proteins in rice blast fungus Magnaporthe oryzae and its host Oryza sativa was analyzed. One thousand two hundred and forty one proteins were predicted as secreted proteins using f...The structure similarity of secreted proteins in rice blast fungus Magnaporthe oryzae and its host Oryza sativa was analyzed. One thousand two hundred and forty one proteins were predicted as secreted proteins using four algorithms based on 11 074 proteins in genome of M. oryzae. One hundred and forty six secreted proteins（ 11. 8% of M. oryzae secretome） were aligned with 116 rice proteins（ 0. 21% of 56 278 rice proteins） using BLAST search on rice genome. One hundred sixteen rice similar proteins participated in rice cell wall modification（ cell wall associated enzymes） and signal transduction（ proteases）. These results imply that both cell wall involved proteins and signal transduction are probably hijacks pathway between host pants and pathogenic fungi. Because these proteins are highly conserved among fungi and plants,the express patterns of these protein coding genes during the interaction process are valuable to study in detail.展开更多
BACKGROUND Secreted protein acidic and rich in cysteine(SPARC)is an extracellular matrixassociated protein.Studies have revealed that SPARC is involved in the cell interaction and function including proliferation,diff...BACKGROUND Secreted protein acidic and rich in cysteine(SPARC)is an extracellular matrixassociated protein.Studies have revealed that SPARC is involved in the cell interaction and function including proliferation,differentiation,and apoptosis.However,the role of SPARC in cancer is controversial,as it was reported as the promoter or suppressor in different cancers.Further,the role of SPARC in lymphoma is unclear.AIM To identify the expression and significance of SPARC in lymphoma,especially in diffuse large B-cell lymphoma(DLBCL).METHODS The expression analysis of SPARC in different cancers was evaluated with Oncomine.The Brune,Eckerle,Piccaluga,Basso,Compagno,Alizadeh,and Rosenwald datasets were included to evaluate the mRNA expression of SPARC in lymphoma.The Cancer Genome Atlas(TCGA)-DLBCL was used to analyze the diagnostic value of SPARC in DLBCL.The Compagno and Brune DLBCL datasets were used for validation.Then,the diagnostic value was evaluated with the receiver operating characteristic(ROC)curve.The Kaplan-Meier plot was conducted with TCGA-DLBCL,and the ROC analysis was performed based on the survival time.Further,the overall survival analysis based on the level of SPARC expression was performed with the GSE4475 and E-TABM-346.The Gene Set Enrichment Analyses(GSEA)was performed to make the underlying mechanism-regulatory networks.RESULTS The pan-cancer analysis of SPARC showed that SPARC was highly expressed in the brain and central nervous system,breast,colon,esophagus,stomach,head and neck,pancreas,and sarcoma,especially in lymphoma.The overexpression of SPARC in lymphoma,especially DLBCL,was confirmed in several datasets.The ROC analysis revealed that SPARC was a valuable diagnostic biomarker.More importantly,compared with DLBCL patients with low SPARC expression,those with higher SPARC expression represented a higher overall survival rate.The ROC analysis showed that SPARC was a favorable prognostic biomarker for DLBCL.Results of the GSEA confirmed that the high expression of SPARC was closely associated with focal adhesion,extracellular matrix receptor interaction,and leukocyte transendothelial migration,which suggested that SPARC may be involved in the regulation of epithelial-mesenchymal transition,KRAS,and myogenesis in DLBCL.CONCLUSION SPARC was highly expressed in DLBCL,and the overexpression of SPARC showed sound diagnostic value.More interestingly,the overexpression of SPARC might be a favorable prognostic biomarker for DLBCL,suggesting that SPARC might be an inducible factor in the development of DLBCL,and inducible SPARC was negative in some oncogenic pathways.All the evidence suggested that inducible SPARC might be a good diagnostic and prognostic biomarker for DLBCL.展开更多
Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was dimini...Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was diminished in the bone of aged and ovariectomized(OVX)mice,as well as in the serum of osteopenia and osteoporosis patients.In vitro loss-of-function and gain-offunction studies revealed that NELL2 facilitated osteoblast differentiation and impeded adipocyte differentiation from stromal progenitor cells.In vivo studies further demonstrated that the deletion of NELL2 in preosteoblasts resulted in decreased cancellous bone mass in mice.Mechanistically,NELL2 interacted with the FNI-type domain located at the C-terminus of Fibronectin 1(Fn1).Moreover,we found that NELL2 activated the focal adhesion kinase(FAK)/AKT signaling pathway through Fn1/integrinβ1(ITGB1),leading to the promotion of osteogenesis and the inhibition of adipogenesis.Notably,administration of NELL2-AAV was found to ameliorate bone loss in OVX mice.These findings underscore the significant role of NELL2 in osteoblast differentiation and bone homeostasis,suggesting its potential as a therapeutic target for managing osteoporosis.展开更多
To address the low efficiency of genetic manipulation and poor hyphal morphology control in Aspergillus oryzae,this study developed a synthetic biology toolkit and identified a key genetic target for morphological eng...To address the low efficiency of genetic manipulation and poor hyphal morphology control in Aspergillus oryzae,this study developed a synthetic biology toolkit and identified a key genetic target for morphological engineering.The toolkit features an RNP-mediated rapid knockout system,serine integrase-based gene integration,and a pipeline for screening high-activity neutral genomic sites.Systematic deletion of seven cell wall integrityrelated genes revealed that disruption of the chitin synthase gene chsY most effectively enhanced protein secretion.TheΔchsY mutant exhibited a 34.8%increase in hyphal diameter and a 30.6%reduction in culture viscosity,coupled with upregulated secretory pathways and an activated unfolded protein response(UPR).Applying this discovery,we engineered a strain expressing a heterologous lipase(TLL),achieving a 52%increase in extracellular activity in flasks.This benefit scaled to bioreactors,with a 42%higher enzyme titer and~50%lower viscosity.Our work provides both a genetic toolkit and a scalable engineering strategy(chsY deletion)to enhance A.oryzae as a cell factory for industrial enzyme production.展开更多
β-Galactosidases are essential for low-lactose milk production.However,most commercial enzymes are meso-philic and unsuitable for high-temperature processing,while others exhibit acidic optimal pH values,which are in...β-Galactosidases are essential for low-lactose milk production.However,most commercial enzymes are meso-philic and unsuitable for high-temperature processing,while others exhibit acidic optimal pH values,which are incompatible with milk's near-neutral pH.The thermostableβ-galactosidase BgaS from Pyrococcus furiosus shows promise as it has an optimum temperature of 90℃ and pH 7.0,yet its heterologous expression in non-food-safe systems limits its application,and its secretory expression remains underexplored.This study constructed a food-safe Bacillus subtilis strain BS801 by CRISPR-Cpf1-mediated scarless knockout of 3 antibiotic resistance genes,namely ble,hyg,bsr,from the high secretion efficient host WB800,and post-culture was found to enhance gene editing efficiency.BgaS was heterologously expressed in BS801,and its secretory expression was optimized by screening 10 Sec-pathway signal peptides(SPs).Among them,4 SPs effectively promoted BgaS secretion.The signal peptide from protein DacB(SP_(dacB))showed the highest efficiency for BgaS secretion,with extracellular enzymatic activity reaching 0.42 U/mL.The recombinant BgaS retained approximately 80%relative activity after 3 h incubation at 80℃.Notably,the enzyme BgaS hydrolyzed lactose in raw milk to a concentration below 0.5%(w/w)within 4 h at 90℃,with the lactose hydrolysis rate reaching 92.64%.These results indicated the enzyme BgaS secreted by strain BS801 had excellent potential for practical application in the dairy industry.展开更多
Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion....Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion. Methods The gene fragments encoding β-galactosidase from two strains of Loctobacillus bulgaricus, wch9901 isolated from yogurt and 1.1480 purchased from the Chinese Academy of Sciences, were amplified and inserted into lactococcal expression vector pMG36e. For fusion expression, the open reading frame of the β-galactosidase gene was amplified, while for non-fusion expression, the open reading frame of the β-galactosidase gene was amplified with its native Shine-Dalgarno sequence upstream. The start codon of the β-galactosidase gene partially overlapped with the stop codon of vector origin open reading frame. Then, the recombinant plasmids were transformed into Escherichia coli DH5α and Lactococcus lactis subsp, lactis MG1363 and confirmed by determining β-galactosidase activities. Results The non-fusion expression plasmids showed a significantly higher β-galactosidase activity in transformed strains than the fusion expression plasmids. The highest enzyme activity was observed in Lactococcus lactis transformed with the non-fusion expression plasmids which were inserted into the β-galactosidase gene from Lactobacillus bulgaricus wch9901. The β-galactosidase activity was 2.75 times as high as that of the native counterpart. In addition, β-galactosidase expressed by recombinant plasmids in Lactococcus lactis could be secreted into the culture medium. The highest secretion rate （27.1%） was observed when the culture medium contained 20 g/L of lactose. Conclusion Different properties of the native bacteria may have some effects on the protein expression of recombinant plasmids. Non-fusion expression shows a higher enzyme activity in host bacteria. There may be a host-related weak secretion signal peptide gene within the structure gene of Lb. bulgaricus β-galactosidase, and its translation product may introduce the enzyme secretion out of cells in special hosts.展开更多
Wnts are a large family of growth factors that mediate essential biological processes like embryogenesis, morpho- genesis and organogenesis. These proteins also play a role in oncogenesis, and they regulate apoptosis ...Wnts are a large family of growth factors that mediate essential biological processes like embryogenesis, morpho- genesis and organogenesis. These proteins also play a role in oncogenesis, and they regulate apoptosis in many tissues. Wnts bind to a membrane receptor complex comprised of a frizzled （FZD） G-protein-coupled receptor and a low-density lipoprotein （LDL） receptor-related protein （LRP）. The formation of this ligand-receptor complex initiates a number of signaling cascades that include the canonical/beta-catenin pathway as well as several noncanonical pathways. In recent years, canonical Wnt signaling has been reported to play a significant role in the control of bone formation. Clinical studies have found that mutations in LRP-5 are associated with reduced bone mineral density （BMD） and fractures. Investigations of knockout and transgenic mouse models of Wnt pathway components have shown that canonical Wnt signaling modulates most aspects ofosteoblast physiology including proliferation, differentiation, function and apoptosis. Transgenic mice expressing a gain of function mutant of LRP-5 in bone, or mice lacking the Wnt antagonist secreted frizzled-related protein-l, exhibit elevated BMD and suppressed osteoblast apoptosis. In addition, preclinical studies with pharmacologic compounds such as those that inhibit glycogen synthase kinase-3β support the importance of the canonical Wnt pathway in modulation of bone formation and osteoblast apoptosis.展开更多
AIM： To investigate the feasibility of detecting methylated fecal DNA as a screening tool for colorectal carcinoma （CRC） and precancerous lesions. METHODS： Methylated secreted frizzled-related protein gene 2 （SF...AIM： To investigate the feasibility of detecting methylated fecal DNA as a screening tool for colorectal carcinoma （CRC） and precancerous lesions. METHODS： Methylated secreted frizzled-related protein gene 2 （SFRP2）, hyperplastic polyposis protein gene （HPP1） and O6-methylguanine-DNA methyltransferase gene （MGMT） in stools from 52 patients with CRC, 35 patients with benign colorectal diseases and 24 normal individuals were analyzed using methylation-specific PCR. RESULTS： Methylated SFRP2, HPP1 and MGMT were detected in 94.2%, 71.2%, 48.1% of CRC patients and 52.4%, 57.1%, 28.6% of adenoma patients, respectively. The overall prevalence of fecal DNA with at least one methylated gene was 96.2% and 81.8% in patients with CRC and precancerous lesions, respectively. In contrast, only one of the 24 normal individuals revealed methylated DNA. These results indicated a 93.7% sensitivity and a 77.1% specificity of the assay for detecting CRC and precancerous lesions. CONCLUSION： IVlethylation testing of fecal DNA using a panel of epigenetic markers may be a simple and promising non-invasive screening method for CRC and precancerous lesions.展开更多
AIM: To investigate the feasibility of detecting aberrantly hypermethylated Wnt-antagonist gene promoters (SFRP2 and WIF-1) in fecal DNA as non-invasive biomarkers for early colorectal cancer (CRC).
基金supported by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)grant LU 2347/3-1(to PL).
文摘Autophagy is well-known for delivering cargo materials to lysosomes for proteolytic digestion.Recently,autophagy has emerged as a key mechanism in unconventional protein secretion(UPS).This perspective introduces unconventional secretion pathways,focusing on secretory autophagy and its role in secreting protein aggregates associated with neurodegenerative disorders.We also explore additional neuronal functions of secretory autophagy beyond the release of protein aggregates.We propose autophagosomes as transport organelles that deliver cargo material directly from the endoplasmatic reticulum(ER)to the plasma membrane rather than solely to lysosomes.
基金supported by the Youth Foundation of Beijing Academy of Agriculture and Forestry Sciences[Grant No.QNJJ202242]the Excellent Young Scholars of Beijing Academy of Agriculture and Forestry Sciences[Grant No.YXQN202205]+3 种基金the Beijing Nova Program[Grant No.20220484052]the National Natural Science Foundation of China[Grant No.31801852]the Collaborative Innovation Center of Beijing Academy of Agriculture and Forestry Sciences[Grant No.KJCX201907-2]the Earmarked Fund for China Agriculture Research System[Grant No.CARS-23-A-05].
文摘The soil-resident pathogen, Plasmodiophora brassicae, infects cruciferous crops, causing obligate parasitic clubroot disease and posing a significant threat to the Brassica vegetable industry in China. To learn more about its pathogenesis, we reported a Nanopore sequencing-derived25.3 Mb high-quality genome sequence of P. brassicae pathotype 4 strain(P.b 4). Comparing the P.b 4 genome with that of the published P.brassicae e3 genome(P.b e3) identified single nucleotide polymorphisms, structural variations, and small insertions and deletions. We then carried out RNA-sequencing of root samples from a clubroot-susceptible line at 5, 14, and 28 days after inoculation(DAI), and classified genes into five categories based on their expression patterns. Interestingly, 158 genes were highly expressed at 14 DAI, which were enriched in budding cell isotropic bud growth, ascospore wall assembly, spore wall assembly, spore wall biogenesis, and ascospore wall biogenesis.Subsequently, we bioinformatically predicted 555 secreted effector candidates, among which only 125 were expressed during infection and had amino acid lengths less than 400. The putative effector Pb010018, which was highly expressed at 14 DAI, was validated to have a signal peptide using a yeast secretion system. Luciferase activity and co-immunoprecipitation assays demonstrated that Pb010018 interacts with serine hydroxymethyltransferase BrSHMT1, and expression analysis showed that SHMT1 was upregulated in both Arabidopsis and B. rapa during infection. Furthermore, after infection, the Arabidopsis shmt1 mutant(atshmt1) showed reduced severity of clubroot disease, together with downregulated expression of Pb010018. Our results offer new insights into plant-pathogen interaction mechanisms, and provide the possibility for improving Brassica resistance to clubroot disease.
基金Supported by Faculty Research Grant from Yonsei University College of Medicine,No.6-2017-0155.
文摘BACKGROUND Pancreatic cancer tissues mainly consist of fibrotic and dense stroma,which limits their therapeutic efficacy.The stromal fibroblasts of pancreatic tumors frequently express the secreted protein acidic and rich in cysteine(SPARC).AIM To assess the impact of SPARC and its oncological relevance in patients undergoing pancreatic cancer resection.METHODS Ninety-one pancreatic ductal adenocarcinoma specimens were obtained from patients with curative resection between January 2009 and December 2015 as a retrospective study.SPARC expression patterns were analyzed using immunohistochemistry.Oncological outcomes were analyzed based on SPARC expression patterns.Oncological outcomes,based on SPARC expression,were analyzed in The Cancer Genome Atlas-Pancreatic Adenocarcinoma cohort(retrieved from a public database).RESULTS Patients with stromal SPARC expression(sSPARC+)had poorer overall survival than that in those without it(sSPARC-)(P=0.035).However,among patients who received adjuvant treatment,no difference was observed in survival between the sSPARC+and the sSPARC-groups(P=0.14).In The Cancer Genome Atlas-Pancreatic Adenocarcinoma samples,the high SPARC expression group exhibited noticeably lower overall survival than that in the low expression group(cutoff:14.1295,P=0.0222).Furthermore,SPARC expression was strongly correlated with the percentage the CD10+stromal component(R2=0.804,P<0.001).CONCLUSION Adjuvant chemotherapy improves survivals in sSPARC+pancreatic cancer patients,indicating suggesting sSPARC expression as a prognostic biomarker and potential indicator for neoadjuvant treatment planning.
基金funded by the National Natural Science Foundation of China(32260042,32460048 and 32160594).
文摘Fungal pathogens utilize intricate signaling networks to regulate growth,morphogenesis,and infection processes,enabling them to adapt to environmental cues and successfully colonize their hosts.Among these networks,the Ras signaling pathway has been extensively studied for its role in fungal morphogenesis and virulence.However,the specific contributions of Ras2 to key pathogenesis processes,such as cytoskeletal organization,appressorium formation,and protein secretion,remain poorly understood.Addressing this gap is critical to understanding the molecular mechanisms underlying fungal virulence and identifying potential targets for disease control strategies.Here,a Ras2 homologue(Cgras2)was identified in Colletotrichum gloeosporioides,a hemibiotrophic fungal pathogen responsible for anthracnose diseases in over 3200 plant species.Using a target deletion mutantΔCgras2,we found that Cgras2 is essential for maintaining conidial germination polarity,cell division,and virulence.Knockout of Cgras2 also impaired appressorium formation and infection by disrupting cytoskeletal networks,including F-actin and septin rings,and by reducing turgor pressure,which is critical for penetration peg formation.Additionally,Cgras2 functions as an upstream regulator of the cAMP signaling pathway,asΔCgras2 mutants exhibit reduced intracellular cAMP levels.Supplementation with exogenous cAMP partially rescued the formation of appressoria and the virulence inΔCgras2 mutant,confirming the regulatory role of Cgras2 in cAMP signaling.RNA-seq analysis further revealed significant downregulation of membrane transporter-encoding genes inΔCgras2 mutants,leading to disruptions in sugar and ion uptake.Secretome analysis demonstrated that Cgras2 also controls extracellular secretion of plant cell wall-degrading enzymes and other virulence factors by regulating the secretion process and genes involved in transcription.Enzymatic activity assays of extracellular hydrolases further confirmed that the absence of Cgras2 significantly impaired secretory capacity.Our findings establish the Cgras2 protein as a central regulator of fungal infection strategies by linking cytoskeletal organization,membrane transport,and protein secretion with Ras2 signaling.These insights provide a foundation for future research into Ras2-mediated signaling networks and identify Cgras2 as a promising target for controlling fungal diseases in plants.
基金Supported by the Special-purpose Scientific Research Foundation for University Doctorate Project of the Ministry of Education of China, No. 301090255
文摘AIM： To investigate the functions of promoter hypermethylation of secreted frizzled-related proteins （sFRPs） genes in colorectal tumorigenesis and progression. METHODS： The promoter hypermethylation and expression of sFRP genes in 72 sporadic colorectal carcinomas, 33 adenomas, 18 aberrant crypt foci （ACF） and colorectal cancer cell lines RKO, HCT116 and SW480 were detected by methylation-specific PCR and reverse transcription PCR, respectively. RESULTS： None of the normal colorectal mucosa tissues showed methylated bands of any of four sFRP genes, sFRP1, 2, 4 and 5 were frequently methylated in colorectal carcinoma, adenoma and ACF （sFRP1 〉 85%, sFRP2 〉75%, sFRP5 〉 50%）, and the differences between three colorectal tissues were not significant （P 〉 0.05）. IVlethylation in colorectal tumors was more frequent than in normal mucosa and adjacent normal mucosa. The mRNA of sFRP1-5 genes was expressed in all normal colorectal mucosa samples. Expression of sFRP1, 2, 4 and 5 and sFRP1, 2 and 5 was downregulated in carcinoma and adenoma, respectively. The downregulation of sFRP2, 4 and 5 was more frequent in carcinoma than in adenoma. Expression of sFRP3 which promoter has no CpG island was downregulated in only a few of colorectal tumor samples （7/105）. The downregulation ofsFRP1, 2, 4 and 5 expression was significantly associated with promoter hypermethylation in colorectal tumor. After cells were treated by DAC/TSA combination, the silenced sFRP mRNA expression could be effectively re-expressed in colorectal cancer cell lines. CONCLUSION： Hypermethylation of sFRP genes is a common early event in the evolution of colorectal tumor, occurring frequently in ACF, which is regarded as the earliest lesion of multistage colorectal carcinogenesis. It appears to functionally silence sFRP genes expression. Methylation of sFRP1, 2 and 5 genes might serve as indicators for colorectal tumor.
基金Supported by Liaoning Education Divison Foundation, No.05L557
文摘AIM： To identify the methylation of secreted frizzled-related protein 1 （SFRP1） in gastric cancer and to investigate the aberrant expression of SFRP1 and its correlation with the clinical pathological features of patients. METHODS： We determined SFRP1 methylation and SFRP1 mRNA expression in 3 gastric cancer cell lines SGC-7901, BGC-823, HGC-27, from 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens by methylation-specific （MSP） PCR and RT-PCR respectively. Fisher＇s exact test was used to analyze the statistical association between clinical pathological data and aberrant expression of SFRP1. RESULTS： In 3 cancer cell lines, BGC-823 and HGC-27 had methylated SFRP1 and lost SFRP1 mRNA expression. After treatment of BGC-823 and HGC-27 with the demethylating agent, 5-aza-2′-deoxycytidine, SFRP1 was re-expressed. In 52 primary gastric cancer specimens and matched tumor adjacent tissue specimens, hypermethylation of SFRP1 was detected in 23 （44%） and 8 （15%） specimens respectively （x^2= 10.34, P 〈 0.01）. Loss of SFRP1 expression was detected in 17（33%） and 6 （12%） specimens respectively （x^2= 6.75, P 〈 0.01）. There was a significant correlation between SFRP1 hypermethylation and SFRP1 expression loss. SFRP1 expression was also correlated significantly with tumor stage and lymph node status, but not with patient sex, age and histological type. CONCLUSION： SFRP1 inactivation is a common and early event caused mainly by hypermethylation in gastric cancer. SFRP1 expression loss may be correlated with tumor metastasis in primary gastric cancer.
基金This work is supported by the National Natural Science Foundation of China （30360061）Natural Science Foundation of Yunnan Province of China （1999C0008Z） National 863 Program of China （2003AA211020）.
文摘Computer based software such as the SignalP v3.0, TargetP v1.01, big-PI predictor and TMHMM v2.0 were combined to predict the signal peptides, and the signal peptide-dependent secreted proteins among the 6 700 ORFs in genome of Saccharomyces cerevisiae. The results showed that 163 proteins were the secreted ones containing signal peptides, and they were secreted via Sec pathway. Among the 163 predicted secreted proteins, the signal peptides of 47 secreted proteins included only the H-domain and C-domain, without N-domain, but the signal peptides of other 116 secreted proteins included all the three domains. There were differences in the constitution of signal peptides between the secreted proteins of S. cerevisiae and of Candida albicans, but the length and amino acids types of their signal peptides were similar in general. Few of the same signal peptides occurred in the secreted proteins of S. cerevisiae genome, and the homology could be compared among the secreted proteins with the same signal peptides. The BLAST 2 SEQUENECES and CLUSTAL W were used to align the two protein sequences and multi-protein sequences, respectively. The alignment result indicated that homology of these sequences with the same signal peptide was very highly conservative in amino acid of complete gene. The effect of the signal peptides in S. cerevisia on expression of foreign eukaryotic secreted proteins is discussed in this paper.
基金the grants from the National Natural Science Foundation of China(U1805232,31770156,and 32172365)the China Postdoctoral Science Foundation(2021M690637)。
文摘The fine-tuned expression dynamics of the effector genes are pivotal for the transition from vegetative growth to host colonization of pathogenic filamentous fungi.However,mechanisms underlying the dynamic regulation of these genes remain largely unknown.Here,through comparative transcriptome and chromatin immunoprecipitation sequencing(ChIP-seq)analyses of the methyltransferase PoKmt6 in rice blast fungus Pyricularia oryzae(syn.Magnaporthe oryzae),we found that PoKmt6-mediated H3K27me3 deposition was enriched mainly at fast-evolving regions and contributed to the silencing of a subset of secreted proteins(SP)and transposable element(TE)families during the vegetative growth of P.oryzae.Intriguingly,we observed that a group of SP genes,which were depleted of H3K27me3 modification,could also be silenced via the H3K27me3-mediated repression of the nearby TEs.In conclusion,our results indicate that H3K27me3 modification mediated by PoKmt6 regulates the expression of some SP genes in fast-evolving regions through the suppression of nearby TEs.
基金Supported by the Natural Science Foundation of Liaoning Province,No.201602817
文摘BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its aberrant methylation in gastric cancer(GC)is still inadequate.In the present research,we performed fundamental research to clarify the precise function of methylation on SPARC and its significance in GC.AIM To investigate promoter methylation and the effects of the SPARC gene in GC cells and tissues and to evaluate its clinical significance.METHODS Plasmids that overexpressed the SPARC gene were transfected into human GC BGC-823 cells;non-transfected cells were used as a control group(NC group).Quantitative real-time polymerase chain reaction and western blotting(WB)were then used to detect the expression of SPARC.Methylation-specific polymerase chain reaction was executed to analyze the gene promoter methylation status.Cell viability was measured by the cell counting kit-8 assay.The migration and invasion ability of cells were detected by scratch assays and transwell chamber assays,respectively.Cell cycle events and apoptosis were observed with a flow cytometer.RESULTS The expression of SPARC mRNA in GC tissues and cells was significantly lower and showed differing degrees of hypermethylation,respectively,than that in normal adjacent tissues and control cells.Treatment with 5-Aza-2’-deoxycytidine(5-Aza-Cdr)was able to restore the expression of SPARC and reverse promoter hypermethylation.Overexpression of the SPARC gene significantly inhibited proliferation,migration,and invasion of GC cells,while also causing cell cycle arrest and apoptosis;the NC group exhibited the opposite effects.CONCLUSION This study demonstrated that SPARC could function as a tumor suppressor and might be silenced by promoter hypermethylation.Furthermore,in GC cells,SPARC inhibited migration,invasion,and proliferation,caused cell cycle arrest at the G0/G1 phase,and promoted apoptosis.
基金supported by the Natural Science Research Project of colleges and Universities in Anhui Province[2022AH052336]High Level Talent Research Initiation Fund Of Anhui Medical College[2023RC004]。
文摘Objective Microcystin-leucine-arginine(MC-LR)exposure induces lipid metabolism disorders in the liver.Secreted frizzled-related protein 5(SFRP5)is a natural antagonist of winglesstype MMTV integration site family,member 5A(Wnt5a)and an anti-inflammatory adipocytokine.In this study,we aimed to investigate whether MC-LR can induce lipid metabolism disorders in hepatocytes and whether SFRP5,which has anti-inflammatory effects,can alleviate the effects of hepatic lipid metabolism by inhibiting the Wnt5a/Jun N-terminal kinase(JNK)pathway.Methods We exposed mice to MC-LR in vivo to induce liver lipid metabolism disorders.Subsequently,mouse hepatocytes that overexpressed SFRP5 or did not express SFRP5 were exposed to MC-LR,and the effects of SFRP5 overexpression on inflammation and Wnt5a/JNK activation by MC-LR were observed.Results MC-LR exposure induced liver lipid metabolism disorders in mice and significantly decreased SFRP5 mRNA and protein levels in a concentration-dependent manner.SFRP5 overexpression in AML12cells suppressed MC-LR-induced inflammation.Overexpression of SFRP5 also inhibited Wnt5a and phosphorylation of JNK.Conclusion MC-LR can induce lipid metabolism disorders in mice,and SFRP5 can attenuate lipid metabolism disorders in the mouse liver by inhibiting Wnt5a/JNK signaling.
基金financed by the National Key Research and Development Program of China(2017YFD0200900)。
文摘Fusarium graminearum,the primary pathogenic fungus responsible for Fusarium head blight(FHB)in wheat,secretes abundant chemical compounds that interact with host plants.In this study,a secreted protein FgHrip1,isolated from the culture filtrate of F.graminearum,was found to induce typical cell death in tobacco.The FgHrip1 gene was then cloned and expressed in Escherichia coli.Further bioassay analysis showed that the recombinant FgHrip1 induced early defense induction events,such as reactive oxygen species(ROS)production,callose deposition,and up-regulation of defense-related genes in tobacco.Furthermore,FgHrip1 significantly enhanced immunity in tobacco seedlings against Pseudomonas syringae pv.tabaci 6605(Pst.6605)and tobacco mosaic virus(TMV).FgHrip1-treated wheat spikes also exhibited defense-related transcript accumulation and developed immunity against FHB infection.Whereas the expression of FgHrip1 was induced during the infection process,the deletion of the gene impaired the virulence of F.graminearum.Our results suggest that FgHrip1triggers immunity and induces disease resistance in tobacco and wheat,thereby providing new insight into strategy for biocontrol of FHB.
基金Supported by National Basic Research Program(2012CB722901)Academic Award for Up-and-coming Doctoral Candidates of Yunnan ProvinceYunnan Agricultural University Innovation Foundation for Postgraduate
文摘The structure similarity of secreted proteins in rice blast fungus Magnaporthe oryzae and its host Oryza sativa was analyzed. One thousand two hundred and forty one proteins were predicted as secreted proteins using four algorithms based on 11 074 proteins in genome of M. oryzae. One hundred and forty six secreted proteins（ 11. 8% of M. oryzae secretome） were aligned with 116 rice proteins（ 0. 21% of 56 278 rice proteins） using BLAST search on rice genome. One hundred sixteen rice similar proteins participated in rice cell wall modification（ cell wall associated enzymes） and signal transduction（ proteases）. These results imply that both cell wall involved proteins and signal transduction are probably hijacks pathway between host pants and pathogenic fungi. Because these proteins are highly conserved among fungi and plants,the express patterns of these protein coding genes during the interaction process are valuable to study in detail.
文摘BACKGROUND Secreted protein acidic and rich in cysteine(SPARC)is an extracellular matrixassociated protein.Studies have revealed that SPARC is involved in the cell interaction and function including proliferation,differentiation,and apoptosis.However,the role of SPARC in cancer is controversial,as it was reported as the promoter or suppressor in different cancers.Further,the role of SPARC in lymphoma is unclear.AIM To identify the expression and significance of SPARC in lymphoma,especially in diffuse large B-cell lymphoma(DLBCL).METHODS The expression analysis of SPARC in different cancers was evaluated with Oncomine.The Brune,Eckerle,Piccaluga,Basso,Compagno,Alizadeh,and Rosenwald datasets were included to evaluate the mRNA expression of SPARC in lymphoma.The Cancer Genome Atlas(TCGA)-DLBCL was used to analyze the diagnostic value of SPARC in DLBCL.The Compagno and Brune DLBCL datasets were used for validation.Then,the diagnostic value was evaluated with the receiver operating characteristic(ROC)curve.The Kaplan-Meier plot was conducted with TCGA-DLBCL,and the ROC analysis was performed based on the survival time.Further,the overall survival analysis based on the level of SPARC expression was performed with the GSE4475 and E-TABM-346.The Gene Set Enrichment Analyses(GSEA)was performed to make the underlying mechanism-regulatory networks.RESULTS The pan-cancer analysis of SPARC showed that SPARC was highly expressed in the brain and central nervous system,breast,colon,esophagus,stomach,head and neck,pancreas,and sarcoma,especially in lymphoma.The overexpression of SPARC in lymphoma,especially DLBCL,was confirmed in several datasets.The ROC analysis revealed that SPARC was a valuable diagnostic biomarker.More importantly,compared with DLBCL patients with low SPARC expression,those with higher SPARC expression represented a higher overall survival rate.The ROC analysis showed that SPARC was a favorable prognostic biomarker for DLBCL.Results of the GSEA confirmed that the high expression of SPARC was closely associated with focal adhesion,extracellular matrix receptor interaction,and leukocyte transendothelial migration,which suggested that SPARC may be involved in the regulation of epithelial-mesenchymal transition,KRAS,and myogenesis in DLBCL.CONCLUSION SPARC was highly expressed in DLBCL,and the overexpression of SPARC showed sound diagnostic value.More interestingly,the overexpression of SPARC might be a favorable prognostic biomarker for DLBCL,suggesting that SPARC might be an inducible factor in the development of DLBCL,and inducible SPARC was negative in some oncogenic pathways.All the evidence suggested that inducible SPARC might be a good diagnostic and prognostic biomarker for DLBCL.
基金supported by grants from National Natural Science Foundation of China(82272444,81972031,81972033)China Postdoctoral Science Foundation(2022M722382)Tianjin Key Medical Discipline(Specialty)Construction Project(TJYXZDXK-032A)。
文摘Neural EGFL-like 2(NELL2)is a secreted protein known for its regulatory functions in the nervous and reproductive systems,yet its role in bone biology remains unexplored.In this study,we observed that NELL2 was diminished in the bone of aged and ovariectomized(OVX)mice,as well as in the serum of osteopenia and osteoporosis patients.In vitro loss-of-function and gain-offunction studies revealed that NELL2 facilitated osteoblast differentiation and impeded adipocyte differentiation from stromal progenitor cells.In vivo studies further demonstrated that the deletion of NELL2 in preosteoblasts resulted in decreased cancellous bone mass in mice.Mechanistically,NELL2 interacted with the FNI-type domain located at the C-terminus of Fibronectin 1(Fn1).Moreover,we found that NELL2 activated the focal adhesion kinase(FAK)/AKT signaling pathway through Fn1/integrinβ1(ITGB1),leading to the promotion of osteogenesis and the inhibition of adipogenesis.Notably,administration of NELL2-AAV was found to ameliorate bone loss in OVX mice.These findings underscore the significant role of NELL2 in osteoblast differentiation and bone homeostasis,suggesting its potential as a therapeutic target for managing osteoporosis.
基金supported by the National Key Research and Development Program of China(project no.2024YFA0918301)the National Natural Science Foundation of China(grant number 32270046).
文摘To address the low efficiency of genetic manipulation and poor hyphal morphology control in Aspergillus oryzae,this study developed a synthetic biology toolkit and identified a key genetic target for morphological engineering.The toolkit features an RNP-mediated rapid knockout system,serine integrase-based gene integration,and a pipeline for screening high-activity neutral genomic sites.Systematic deletion of seven cell wall integrityrelated genes revealed that disruption of the chitin synthase gene chsY most effectively enhanced protein secretion.TheΔchsY mutant exhibited a 34.8%increase in hyphal diameter and a 30.6%reduction in culture viscosity,coupled with upregulated secretory pathways and an activated unfolded protein response(UPR).Applying this discovery,we engineered a strain expressing a heterologous lipase(TLL),achieving a 52%increase in extracellular activity in flasks.This benefit scaled to bioreactors,with a 42%higher enzyme titer and~50%lower viscosity.Our work provides both a genetic toolkit and a scalable engineering strategy(chsY deletion)to enhance A.oryzae as a cell factory for industrial enzyme production.
基金supported by the National Key Research and Devel-opment Program of China(2021YFE0101800).
文摘β-Galactosidases are essential for low-lactose milk production.However,most commercial enzymes are meso-philic and unsuitable for high-temperature processing,while others exhibit acidic optimal pH values,which are incompatible with milk's near-neutral pH.The thermostableβ-galactosidase BgaS from Pyrococcus furiosus shows promise as it has an optimum temperature of 90℃ and pH 7.0,yet its heterologous expression in non-food-safe systems limits its application,and its secretory expression remains underexplored.This study constructed a food-safe Bacillus subtilis strain BS801 by CRISPR-Cpf1-mediated scarless knockout of 3 antibiotic resistance genes,namely ble,hyg,bsr,from the high secretion efficient host WB800,and post-culture was found to enhance gene editing efficiency.BgaS was heterologously expressed in BS801,and its secretory expression was optimized by screening 10 Sec-pathway signal peptides(SPs).Among them,4 SPs effectively promoted BgaS secretion.The signal peptide from protein DacB(SP_(dacB))showed the highest efficiency for BgaS secretion,with extracellular enzymatic activity reaching 0.42 U/mL.The recombinant BgaS retained approximately 80%relative activity after 3 h incubation at 80℃.Notably,the enzyme BgaS hydrolyzed lactose in raw milk to a concentration below 0.5%(w/w)within 4 h at 90℃,with the lactose hydrolysis rate reaching 92.64%.These results indicated the enzyme BgaS secreted by strain BS801 had excellent potential for practical application in the dairy industry.
基金a scientific research grant from Health Bureau of Sichuan Province (No. F0201)
文摘Objective To construct four recombinant Lactococcus lactis strains exhibiting high β-galactosidase activity in fusion or non-fusion ways, and to study the influence factors for their protein expression and secretion. Methods The gene fragments encoding β-galactosidase from two strains of Loctobacillus bulgaricus, wch9901 isolated from yogurt and 1.1480 purchased from the Chinese Academy of Sciences, were amplified and inserted into lactococcal expression vector pMG36e. For fusion expression, the open reading frame of the β-galactosidase gene was amplified, while for non-fusion expression, the open reading frame of the β-galactosidase gene was amplified with its native Shine-Dalgarno sequence upstream. The start codon of the β-galactosidase gene partially overlapped with the stop codon of vector origin open reading frame. Then, the recombinant plasmids were transformed into Escherichia coli DH5α and Lactococcus lactis subsp, lactis MG1363 and confirmed by determining β-galactosidase activities. Results The non-fusion expression plasmids showed a significantly higher β-galactosidase activity in transformed strains than the fusion expression plasmids. The highest enzyme activity was observed in Lactococcus lactis transformed with the non-fusion expression plasmids which were inserted into the β-galactosidase gene from Lactobacillus bulgaricus wch9901. The β-galactosidase activity was 2.75 times as high as that of the native counterpart. In addition, β-galactosidase expressed by recombinant plasmids in Lactococcus lactis could be secreted into the culture medium. The highest secretion rate （27.1%） was observed when the culture medium contained 20 g/L of lactose. Conclusion Different properties of the native bacteria may have some effects on the protein expression of recombinant plasmids. Non-fusion expression shows a higher enzyme activity in host bacteria. There may be a host-related weak secretion signal peptide gene within the structure gene of Lb. bulgaricus β-galactosidase, and its translation product may introduce the enzyme secretion out of cells in special hosts.
文摘Wnts are a large family of growth factors that mediate essential biological processes like embryogenesis, morpho- genesis and organogenesis. These proteins also play a role in oncogenesis, and they regulate apoptosis in many tissues. Wnts bind to a membrane receptor complex comprised of a frizzled （FZD） G-protein-coupled receptor and a low-density lipoprotein （LDL） receptor-related protein （LRP）. The formation of this ligand-receptor complex initiates a number of signaling cascades that include the canonical/beta-catenin pathway as well as several noncanonical pathways. In recent years, canonical Wnt signaling has been reported to play a significant role in the control of bone formation. Clinical studies have found that mutations in LRP-5 are associated with reduced bone mineral density （BMD） and fractures. Investigations of knockout and transgenic mouse models of Wnt pathway components have shown that canonical Wnt signaling modulates most aspects ofosteoblast physiology including proliferation, differentiation, function and apoptosis. Transgenic mice expressing a gain of function mutant of LRP-5 in bone, or mice lacking the Wnt antagonist secreted frizzled-related protein-l, exhibit elevated BMD and suppressed osteoblast apoptosis. In addition, preclinical studies with pharmacologic compounds such as those that inhibit glycogen synthase kinase-3β support the importance of the canonical Wnt pathway in modulation of bone formation and osteoblast apoptosis.
基金grant from Scientific and Technologic Bureau of Wuxi, No. CS055010
文摘AIM： To investigate the feasibility of detecting methylated fecal DNA as a screening tool for colorectal carcinoma （CRC） and precancerous lesions. METHODS： Methylated secreted frizzled-related protein gene 2 （SFRP2）, hyperplastic polyposis protein gene （HPP1） and O6-methylguanine-DNA methyltransferase gene （MGMT） in stools from 52 patients with CRC, 35 patients with benign colorectal diseases and 24 normal individuals were analyzed using methylation-specific PCR. RESULTS： Methylated SFRP2, HPP1 and MGMT were detected in 94.2%, 71.2%, 48.1% of CRC patients and 52.4%, 57.1%, 28.6% of adenoma patients, respectively. The overall prevalence of fecal DNA with at least one methylated gene was 96.2% and 81.8% in patients with CRC and precancerous lesions, respectively. In contrast, only one of the 24 normal individuals revealed methylated DNA. These results indicated a 93.7% sensitivity and a 77.1% specificity of the assay for detecting CRC and precancerous lesions. CONCLUSION： IVlethylation testing of fecal DNA using a panel of epigenetic markers may be a simple and promising non-invasive screening method for CRC and precancerous lesions.
基金Supported by The National Natural Science Foundation of China,No.81101868The Natural Science Foundation of Hubei Province of China,No.2011CDB505
文摘AIM: To investigate the feasibility of detecting aberrantly hypermethylated Wnt-antagonist gene promoters (SFRP2 and WIF-1) in fecal DNA as non-invasive biomarkers for early colorectal cancer (CRC).
