Nasopharyngeal carcinoma(NPC)is a malignant tumor arising from the nasopharyngeal epithelium.It consists of undifferentiated squamous cells in the nasopharynx.This type of epithelial cell neoplasm is globally distribu...Nasopharyngeal carcinoma(NPC)is a malignant tumor arising from the nasopharyngeal epithelium.It consists of undifferentiated squamous cells in the nasopharynx.This type of epithelial cell neoplasm is globally distributed,with the highest prevalence observed in certain regions of the world.It has been known since ancient times.The incidence of NPC is steadily decreasing as data on the molecular factors involved in the pathogenesis of NPC accumulate.Glycoproteins are characterized by polymers of saccharides attached to the amino acid sequences of proteins during the process of glycosylation.They are present in all animal cells and are especially abundant on the surface of tumor cells.Alterations in expression of cellular glycoproteins have recently attracted attention as a key component of neoplastic progression.Tumor-associated glycoproteins may serve as a hallmark of cancer cells and thus represent novel diagnostic and even therapeutic targets.Interest in the role of glycoproteins in cancer in general and specifically in NPC pathology has steadily increased over the past fifty years,reaching over thousands and two hundred publications in the last five years,respectively.Here,data on a specific class of proteins,glycoproteins,involved in tumorigenesis of NPCs are summarized,with a focus on a few of the best-studied ones.Relevant studies performed mainly in the last five years were retrieved and collected through the PubMed system.展开更多
During mammalian fertilisation, the zona pellucida （ZP） matrix surrounding the oocyte is responsible for the binding of the spermatozoa to the oocyte and induction of the acrosome reaction （AR） in the ZP-bound spe...During mammalian fertilisation, the zona pellucida （ZP） matrix surrounding the oocyte is responsible for the binding of the spermatozoa to the oocyte and induction of the acrosome reaction （AR） in the ZP-bound spermatozoon. The AR is crucial for the penetration of the ZP matrix by spermatozoa. The ZP matrix in mice is composed of three glycoproteins designated ZP1, ZP2 and ZP3, whereas in humans, it is composed of four （ZP1, ZP2, ZP3 and ZP4）. ZP3 acts as the putative primary sperm receptor and is responsible for AR induction in mice, whereas in humans （in addition to ZP3）, ZP1 and ZP4 also induce the AR. The ability of ZP3 to induce the AR resides in its C-terminal fragment. O-linked glycans are critical for the murine ZP3-mediated AR. However, N-linked glycans of human ZP1, ZP3 and ZP4 have important roles in the induction of the AR. Studies with pharmacological inhibitors showed that the ZP3-induced AR involves the activation of the Gi-coupled receptor pathway, whereas ZP1- and ZP4-mediated ARs are independent of this pathway. The ZP3-induced AR involves the activation of T-type voltage-operated calcium channels （VOCCs）, whereas ZP1- and ZP4-induced ARs involve both T- and L-type VOCCs. To conclude, in mice, ZP3 is primarily responsible for the binding of capacitated spermatozoa to the ZP matrix and induction of the AR, whereas in humans （in addition to ZP3）, ZP1 and ZP4 also participate in these stages of fertilisation.展开更多
Aberrations in protein glycosylation and polysaccharides play a pivotal role in pancreatic tumorigenesis, influencing cancer progression, metastasis, immunoresponse and chemoresistance. Abnormal expression in sugar mo...Aberrations in protein glycosylation and polysaccharides play a pivotal role in pancreatic tumorigenesis, influencing cancer progression, metastasis, immunoresponse and chemoresistance. Abnormal expression in sugar moieties can impact the function of various glycoproteins, including mucins, surface receptors, adhesive proteins, proteoglycans, as well as their effectors and binding ligands, resulting in an increase in pancreatic cancer invasiveness and a cancerfavored microenvironment. Recent advance in glycoproteomics, glycomics and other chemical biology techniques have been employed to better understand the complex mechanism of glycosylation events and how they orchestrate molecular activities in genomics, proteomics and metabolomics implicated in pancreatic adenocarcinoma. A variety of strategies have been demonstrated targeting protein glycosylation and polysaccharides for diagnostic and therapeutic development.展开更多
Objective: To observe the effect of Xiaoyu Zhixue tablet (消瘀止血片,XYZXT) on the expression of platelet membrane glycoproteins in patients with hemorrhagic thrombopathy, and to explore its possible mechanism. Method...Objective: To observe the effect of Xiaoyu Zhixue tablet (消瘀止血片,XYZXT) on the expression of platelet membrane glycoproteins in patients with hemorrhagic thrombopathy, and to explore its possible mechanism. Methods: The total of 148 patients with hemorrhagic thrombopathy were randomly divided into two groups, the traditional Chinese medicicne (TCM) group (n=98) treated with XYZXT and the Western medicine (WM) group (n=50) treated with adrenosin, vitamins C, K and P, both for 6 months. The therapeutic effect and the recovery rate of platelet aggregation in the two groups were observed. And platelet membrane glycoprotein (GP) Ⅰb/Ⅸ, GPⅡb/Ⅲa complexes, GPⅠb, GPⅡb, GP Ⅲa and P-selectin were analyzed by flow cytometry in both groups before and after treatment and also in 34 normal healthy subjects. Results: The total effective rate of hemostasis was 89. 8% in TCM group and 54. 0% in the WM group (x2=45.83, P<0.01), and the recovery rate of platelet aggregation was 72.4% and 4.0% respectively (x2=62.06, P<0.01). The fluorescence intensity of GP Ⅰ b/Ⅸ, GPⅡb/Ⅲa complexes, GPⅠb, GPⅢa and P-selectin were lower in both groups before treatment than those in the healthy subjects. Expression of above-mentioned marks was elevated in TCM group after 6 months' therapy, which was insignificantly different as compared with the healthy subjects (P>0.05) and higher than those in the WM group (P<0.05). Conclusion: One of the mechanisms in treating hemorrhagic thrombopathy with XYZXT is that it could regulate the expression of GP Ⅰb/Ⅸ, GPⅡ b/Ⅲa complexes, GPⅠb, GPⅢa and P-selectin at the level of receptor protein.展开更多
The analysis of endogenous glycoproteins and glycopeptides in human body fluids is of great importance for screening and discovering disease biomarkers with clinical significance.However,the presence of interfering su...The analysis of endogenous glycoproteins and glycopeptides in human body fluids is of great importance for screening and discovering disease biomarkers with clinical significance.However,the presence of interfering substances makes the direct quantitative detection of low-abundance glycoproteins and glycopeptides in human body fluids one of the great challenges in analytical chemistry.Magnetic solid phase extraction(MSPE)has the advantages of easy preparation,low cost and good magnetic responsiveness.Magnetic adsorbents are the core of MSPE technology,and magnetic adsorbents based on different functional materials are widely used in the quantitative analysis of glycoproteins and glycopeptides in human body fluids,making it possible to analyze glycoproteins and glycopeptides with low abundance as well as multiple types,which provides a technical platform for screening and evaluating glycoproteins and glycopeptides in body fluids as disease biomarkers.In this paper,we focus on the recent advances in the application of MSPE technology and magnetic adsorbents for the separation and enrichment of glycoproteins and glycopeptides in human body fluids,and the future trends and application prospects in this field are also presented.展开更多
Early diagnosis of pregnancy plays an important role to minimize reproductive losses in farm animals.There are several methods for pregnancy diagnosis like profiling of reproductive hormones(such as progesterone and e...Early diagnosis of pregnancy plays an important role to minimize reproductive losses in farm animals.There are several methods for pregnancy diagnosis like profiling of reproductive hormones(such as progesterone and estrone sulfate),but sometimes they provide false-positive results.Embryo specific pregnancy markers,which delineate the presence and viability of the embryo,are considered as perfect for pregnancy determination.Pregnancy-associated glycoproteins are distinguished as the best indicator for the determination of early pregnancy,fetal number,and birth weight of kids.Pregnancy-associated glycoproteins are structurally correlated to aspartic proteinase and are communicated in the external epithelial cell layer of the placenta.They have been found to share about half amino acid sequence identity with pepsinogen,pepsin,cathepsin D and E.Dislike different individuals from aspartic proteinase family,numerous pregnancy-associated glycoproteins appear to be latent compound as a result of amino acid substitutions in and around the catalytic site.This review is to discuss the scope and prospects of pregnancy-associated glycoproteins as a pregnancy marker in farm animals,more specifically in goats.展开更多
Chronic infection by either hepatitis B virus(HBV)or hepatitis C virus(HCV)share epidemiological characteristics with risks for development of severe complications such as liver cirrhosis and hepatocellular carcinoma....Chronic infection by either hepatitis B virus(HBV)or hepatitis C virus(HCV)share epidemiological characteristics with risks for development of severe complications such as liver cirrhosis and hepatocellular carcinoma.HBV and HCV also share a high genetic variability. Among highly variable regions,viral genes encoding surface proteins(hepatitis B surface antigen,E1/E2 HCV glycoproteins)play key roles in the stimulation of the host-related immune response and viral entry into hepatocytes.Specific segments of HBV envelope proteins(preS1,"a"determinant)are crucial in the entry process into permissive cells.HCV entry is a complex multistep process involving multiple cell cofactors (glycosaminoglycans,low density lipoprotein receptor, SR-B1,CD81,claudin-1,occludin,EGFR,EphA2)in the interaction with HCV E1/E2 envelope glycoproteins.In vitro both viruses can be controlled by antibody-me-diated neutralization targeting viral envelope,also essential in preventing HBV infection in vivo as observed through successful vaccination using HBs antigen.But preventive vaccination and/or therapeutic pressure can influence HBV and HCV variability.For HBV,the patterns of antiviral drug resistance in chronic hepatitis are complex and the original pol/S gene overlap has to be taken into account.Treatment-induced HBV mutations in pol could indeed generate S mutants with subsequent modified antigenicity or increased cancer induction.Variability of HBV and HCV envelope proteins combining high exposure to selective pressures and crucial functional roles require investigation in the context of diagnostic,vaccination and treatment tools.In this editorial a synthesis is performed of HBV and HCV envelope properties at the entry step and as antigenic proteins,and the subsequent clinical impact.展开更多
Discrimination of glycoproteins and cell types is a significant but difficult issue.Herein,we presented a novel fluorescence sensor array for the detection and identification of glycoproteins and cancer cells based on...Discrimination of glycoproteins and cell types is a significant but difficult issue.Herein,we presented a novel fluorescence sensor array for the detection and identification of glycoproteins and cancer cells based on the specific affinity between boronic acid-containing carbon dots(BA-CDs)and cis-diol residues of polysaccharides.The differential binding affinity of three BA-CDs to various glycoproteins resulted in a different fluorescence turn-on signal pattern caused by aggregation-enhanced emission(AEE),along with negligible response from other proteins.Therefore,BA-CDs encompassing sensing elements and signal indicator into one can enable a fast and accurate discrimination of glycoproteins with simple and easy operation.Seven glycoproteins could be well discriminated at a very low concentration of 10 nmol/L.The discriminating capability of glycoproteins is not sacrificed in both human urine and serum.Notably,different glycoprotein compositions of cancer cells provide more recognizable features for identification of cancer cells,comparing to the total protein.Five cell types could be identified in 15 min at a low concentration of 1000 cells/mL.This method is fast,accurate,and easy operation,and has a potential application in cancer diagnosis.展开更多
Antifreeze glycoproteins(AFGPs)facilitate the survival of various organisms in the polar region by preventing internal ice accumulation via an adsorption-inhibition mechanism.Inhibition of AFGP antifreeze activity by ...Antifreeze glycoproteins(AFGPs)facilitate the survival of various organisms in the polar region by preventing internal ice accumulation via an adsorption-inhibition mechanism.Inhibition of AFGP antifreeze activity by the borate buffers has been widely acknowledged as the direct experimental evidence supporting the hydroxyl,rather than methyl,binding mechanism.On the other hand,perturbation of borate binding on the AFGP configuration,which might have considerable influence on the binding efficiency of not only the hydroxyl but also the methyl groups,has rarely been quantitatively examined.Herein we studied,using molecular dynamics simulations,the perturbation on the configuration of a solvated AFGP8 protein induced by the binding of one single borate anion.Near the freezing point,this binding not only makes the disaccharide groups adjacent to the borate-binding disaccharide close to each other but also affects the entire AFGP8 conformation.The structural changes induced by the binding of borate on different disaccharide sidechains exhibit clear site-specificities and the effect of borate binding on the structural changes is significantly reduced at higher temperatures.Our study is valuable for further understanding the relationship between the structure and antifreeze activity of these antifreeze glycoproteins.展开更多
Glycoproteins from tumor cells isolated by Con A, PHAE and RCAI, were coupled to horse radish peroxidase and then used as reporters to evaluate the oligosaccharides change on serum glycoproteins in digestive tract dis...Glycoproteins from tumor cells isolated by Con A, PHAE and RCAI, were coupled to horse radish peroxidase and then used as reporters to evaluate the oligosaccharides change on serum glycoproteins in digestive tract diseases and individual healthy persons. A value 2 standard deviation above the mean of the healthy person group was considered positive. The results indicated that the positive rates of the oligosaccharides bound with Con A, PHA-E and RCAI were 51 % (61/119) . 70. 6% (84/119) , and 76. 4% (91/119) in patients with gastric cancer: 53. 3% (16/30),46. 7% ( 14/30) and 66. 7% (20/30) in esophageal cancers; 28. 5% (15/49), 49. 0% (24/49) and .46. 9% (23/49) in colorectal cancer; 78. 1% (25/ 32) ,81. 3% (26/32) and 31. 3% (10/32) in gallbladder tumors; 60. 4% (29/48), 54. 1% (26/48) and 39. 5% (19/48) in hepatocellular cancer. The positive rates among the patients with benign diseases were also found to be 12. 7% (16/126), 15. 5% (20/126) and 26. 2% (33/126). However, the expression of the oligosaccharide moieties recognized by WGA on the glycoprotein bound with Con A, was significantly lower in the serum of patients with tumors than in those with benign disease and in healthy individuals (P<0. 01 , P<0. 01).展开更多
The glycosylation of proteins is responsible for their structural and functional roles in many cellular activities.This work describes a strategy that combines an efficient release, labeling and liquid chromatography...The glycosylation of proteins is responsible for their structural and functional roles in many cellular activities.This work describes a strategy that combines an efficient release, labeling and liquid chromatography–mass spectral analysis with the use of a comprehensive database to analyze N-glycans. The analytical method described relies on a recently commercialized kit in which quick deglycosylation is followed by rapid labeling and cleanup of labeled glycans. This greatly improves the separation, mass spectrometry（MS） analysis and fluorescence detection of N-glycans. A hypothetical database, constructed using Glyc Resoft, provides all compositional possibilities of N-glycans based on the common sugar residues found in N-glycans. In the initial version this database contains ＆gt; 8,700 N-glycans, and is compatible with MS instrument software and expandable. N-glycans from four different well-studied glycoproteins were analyzed by this strategy. The results provided much more accurate and comprehensive data than that had been previously reported. This strategy was then used to analyze the N-glycans present on the membrane glycoproteins of gastric carcinoma cells with different degrees of differentiation. Accurate and comprehensive N-glycan data from those cells was obtained efficiently and their differences were compared corresponding to their differentiation states. Thus, the novel strategy developed greatly improves accuracy, efficiency and comprehensiveness of N-glycan analysis.展开更多
The authors carried out a steady and unsteady mass transfer studies to simulate both the release of proteins in physiologic environments and proteins transport through a tissue or organ from polymeric capsules by usin...The authors carried out a steady and unsteady mass transfer studies to simulate both the release of proteins in physiologic environments and proteins transport through a tissue or organ from polymeric capsules by using a substance, the rhodamine B isothiocyanate dextran (RBID) that mimics the behaviour of glycoproteins such as vascular endothelial growth factor (VEFG). These studies highlighted the importance of electrostatic interactions between alginate and proteins in the release processes. Thereby, this fact has opened new perspectives in order to use these kind of capsules in protein recognition processes. The electrostatic interactions between alginate and RBID allow pH-dependent controlled release systems that simulate the behaviour of glycoproteins.展开更多
This study aimed to isolate and characterize the structures of glycoproteins from peas and determine their hypoglycemic activity.The crude pea glycoproteins(PGP)were extracted by hot water and purified by diethylamino...This study aimed to isolate and characterize the structures of glycoproteins from peas and determine their hypoglycemic activity.The crude pea glycoproteins(PGP)were extracted by hot water and purified by diethylaminoethyl(DEAE)-Sepharose chromatography and Sephadex G-100 size-exclusion chromatography in sequence.Then three main fractions were obtained,namely PGP1,PGP2 and PGP3,with molecular weights of 897615,846740 and 1194692 Da,respectively.The physical and chemical properties of the three fractions were evaluated and compared by Fourier transform infrared spectroscopy(FT-IR),nuclear magnetic resonance(NMR),scanning electron microscope(SEM),high performance liquid chromatography(HPLC)and other analytical techniques.The fraction PGP2 with the highest hypoglycemic activity,was screened using the Caco-2 monolayer cell model.It can inhibit the uptake of glucose in the small intestine,as well as the activities of maltase and sucrase.After simulated gastrointestinal digestion,PGP2 signifi cantly enhanced the inhibitory effect of α-glucosidase,and slightly reduced the inhibitory ability ofα-amylase.In summary,PGP2 possessed strong hypoglycemic activity after digestion.These results indicated that PGP2 has the potential to be developed into a functional food or natural medicine for the treatment of type 2 diabetes mellitus.展开更多
Baculovirus can transduce a wide range of mammalian cells and is considered a promising gene therapy vector. However,the low transduction efficiency of baculovirus into many mammalian cells limits its practical applic...Baculovirus can transduce a wide range of mammalian cells and is considered a promising gene therapy vector. However,the low transduction efficiency of baculovirus into many mammalian cells limits its practical application. Co-expressing heterologous viral glycoproteins(GPs), such as vesicular stomatitis virus G protein(VSV G), with baculovirus native envelope protein GP64 is one of the feasible strategies for improving virus transduction. Tick-borne thogotoviruses infect mammals and their GPs share sequence/structure homology and common evolutionary origins with baculovirus GP64.Herein, we tested whether thogotovirus GPs could facilitate the entry of the prototype baculovirus Autographa californica multiple multiple nucleopolyhedrovirus(AcMNPV) into mammalian cells. The gp genes of two thogotoviruses, Thogoto virus and Dhori virus, were inserted into the AcMNPV genome. Both GPs were properly expressed and incorporated into the envelope of the recombinant AcMNPVs. The transduction rates of recombinant AcMNPVs expressing the two thogotovirus GPs increased for approximately 4–12 fold compared to the wild type AcMNPV in six of the 12 tested mammalian cell lines. It seemed that thogotovirus GPs provide the recombinant AcMNPVs with different cell tropisms and showed better performance in several mammalian cells compared to VSV G incorporated AcMNPV. Further studies showed that the improved transduction was a result of augmented virus-endosome fusion and endosome escaping, rather than increased cell binding or internalization. We found the AcMNPV envelope protein GP64-mediated fusion was enhanced by the thogotovirus GPs at relatively higher p H conditions. Therefore, the thogotovirus GPs represent novel candidates to improve baculovirus-based gene delivery vectors.展开更多
Objective： Hepatocellular carcinoma （HCC） is a leading cause of cancer-related deaths. Novel serum biomarkers are required to increase the sensitivity and specificity of serum screening for early HCC diagnosis. Thi...Objective： Hepatocellular carcinoma （HCC） is a leading cause of cancer-related deaths. Novel serum biomarkers are required to increase the sensitivity and specificity of serum screening for early HCC diagnosis. This study employed a quantitative proteomic strategy to analyze the differential expression of serum glycoproteins between HCC and normal control serum samples. Methods： Lectin affinity chromatography （LAC） was used to enrich glycoproteins from the serum samples. Quantitative mass spectrometric analysis combined with stable isotope dimethyl labeling and 2D liquid chromatography （LC） separations were performed to examine the differential levels of the detected proteins between HCC and control serum samples. Western blot was used to analyze the differential expression levels of the three serum proteins. Results： A total of 2,280 protein groups were identified in the serum samples from HCC patients by using the 2D LC-MS/MS method. Up to 36 proteins were up-regulated in the HCC serum, whereas 19 proteins were down-regulated. Three differential glycoproteins, namely, fibrinogen gamma chain （FGG）, FOS-like antigen 2 （FOSL2）, and a-l, 6-mannosylglycoprotein 6-^-N-acetylglucosaminyltransferase B （MGATSB） were validated by Western blot. All these three proteins were up-regulated in the HCC serum samples. Conclusion： A quantitative glycoproteomic method was established and proven useful to determine potential novel biomarkers for HCC.展开更多
Endogenous retroviruses(ERVs) are a component of the vertebrate genome and originate from exogenous infections of retroviruses in the germline of the host. ERVs have coevolved with their hosts over millions of years. ...Endogenous retroviruses(ERVs) are a component of the vertebrate genome and originate from exogenous infections of retroviruses in the germline of the host. ERVs have coevolved with their hosts over millions of years. Envelope glycoproteins of endogenous retroviruses are often expressed in the mammalian placenta, and their potential function has aroused considerable research interest, including the manipulation of maternal physiology to benefit the fetus. In most mammalian species, trophoblast fusion in the placenta is an important event, involving the formation of a multinucleated syncytiotrophoblast layer to fulfill essential fetomaternal exchange functions. The key function in this process derives from the envelope genes of endogenous retroviruses, namely syncytins, which show fusogenic properties and placenta-specific expression. This review discusses the important role of the recognized endogenous retrovirus envelope glycoproteins in the mammalian placenta.展开更多
In order to select an optimum extraction method for the target glycoprotein （TGP） from jellyfish （Rhopilema esculentum） oral-arms, a high performance liquid chromatography （HPLC）-assay for the determination of t...In order to select an optimum extraction method for the target glycoprotein （TGP） from jellyfish （Rhopilema esculentum） oral-arms, a high performance liquid chromatography （HPLC）-assay for the determination of the TGP was developed Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear （r= 0.9984, y=4.5895x＋47.601） over concentrations ranging from 50 to 400mgL^-1. The mean extraction recovery was 97.84% （CV2.60%）. The fractions containing TGP were isolated from jellyfish （R esculentum） oral-arms by four extraction methods： 1） water extraction （WE）, 2） phosphate buffer solution （PBS） extraction （PE）, 3） ultrasound-assisted water extraction （UA-WE）, 4） ultrasound-assisted P/3S extraction （UA-PE）. The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL （7.8 mm×300 ram） column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.展开更多
Ebolaviruses are highly dangerous pathogens exhibiting extreme virulence in humans and nonhuman primates. The majority of ebolavirus species, most notably Zaire ebolavirus, can cause Ebola virus disease(EVD), formerly...Ebolaviruses are highly dangerous pathogens exhibiting extreme virulence in humans and nonhuman primates. The majority of ebolavirus species, most notably Zaire ebolavirus, can cause Ebola virus disease(EVD), formerly known as Ebola hemorrhagic fever, in humans. EVD is associated with case-fatality rates as high as 90%, and there is currently no specific treatment or licensed vaccine available against EVD. Understanding the molecular biology and pathogenesis of ebolaviruses is important for the development of antiviral therapeutics. Ebolavirus encodes several forms of glycoproteins(GPs), which have some interesting characteristics, including the transcriptional editing coding strategy and extensive O-glycosylation modification, clustered in the mucin-like domain of GP1, full-length GP(GP_(1,2)), and shed GP. In addition to the canonical role of the spike protein, GP_(1,2), in viral entry, ebolavirus GPs appear to have multiple additional functions,likely contributing to the complex pathogenesis of the virus. Here, we review the roles of ebolavirus GPs in viral pathogenesis.展开更多
Sialylated N-glycan isomers withα2-3 orα2-6 linkage(s)have distinctive roles in glycoproteins,but are difficult to distinguish.Wild-type(WT)and glycoengineered(mutant)therapeutic glycoproteins,cytotoxic T lymphocyte...Sialylated N-glycan isomers withα2-3 orα2-6 linkage(s)have distinctive roles in glycoproteins,but are difficult to distinguish.Wild-type(WT)and glycoengineered(mutant)therapeutic glycoproteins,cytotoxic T lymphocyte-associated antigen-4-immunoglobulin(CTLA4-Ig),were produced in Chinese hamster ovary cell lines;however,their linkage isomers have not been reported.In this study,N-glycans of CTLA4-Igs were released,labeled with procainamide,and analyzed by liquid chromatography-tandem mass spectrometry(MS/MS)to identify and quantify sialylated N-glycan linkage isomers.The linkage isomers were distinguished by comparison of 1)intensity of the N-acetylglucosamine ion to the sialic acid ion(Ln/Nn)using different fragmentation stability in MS/MS spectra and 2)retention time-shift for a selective m/z value in the extracted ion chromatogram.Each isomer was distinctively identified,and each quantity(>0.1%)was obtained relative to the total N-glycans(100%)for all observed ionization states.Twenty sialylated N-glycan isomers with onlyα2-3 linkage(s)in WT were identified,and each isomer's sum of quantities was 50.4%.Furthermore,39 sialylated N-glycan isomers(58.8%)in mono-(3 N-glycans;0.9%),bi-(18;48.3%),tri-(14;8.9%),and tetra-(4;0.7%)antennary structures of mutant were obtained,which comprised mono-(15 N-glycans;25.4%),di-(15;28.4%),tri-(8;4.8%),and tetra-(1;0.2%)sialylation,respectively,with onlyα2-3(10 N-glycans;4.8%),bothα2-3 andα2-6(14;18.4%),and onlyα2-6(15;35.6%)linkage(s).These results are consistent with those forα2-3 neuraminidase-treated N-glycans.This study generated a novel plot of Ln/Nn versus retention time to distinguish sialylated N-glycan linkage isomers in glycoprotein.展开更多
L-ficolin, one of lectin families, is a recently identified complement factor that initiates lectin pathway of complement. Little is known about its role in viral hepatitis. In the present study, we found that L-ficol...L-ficolin, one of lectin families, is a recently identified complement factor that initiates lectin pathway of complement. Little is known about its role in viral hepatitis. In the present study, we found that L-ficolin in serum from 103 patients with hepatitis C virus （HCV）, were significantly higher than that in 150 healthy controls. We further found that L-ficolin expressions were significantly increased in vitro study by HCV JFH-1 infected human hepatocyte cell line Huh7.5.1. Investigation of the mechanisms of the L-ficolin action on HCV demonstrated that L-ficolin protein could recognize and bind to envelope glycoproteins E1 and E2 of HCV, activating the lectin complement pathway-mediated cytolytic activity in HCV-infected hepatocyte. This interaction between L-ficolin and HCV E1 and E2 glycoproteins was attributed to the N-glycans of E1 and E2. These findings provide new insights into the biological functions of L-ficolin in clinically important hepatic viral diseases.展开更多
文摘Nasopharyngeal carcinoma(NPC)is a malignant tumor arising from the nasopharyngeal epithelium.It consists of undifferentiated squamous cells in the nasopharynx.This type of epithelial cell neoplasm is globally distributed,with the highest prevalence observed in certain regions of the world.It has been known since ancient times.The incidence of NPC is steadily decreasing as data on the molecular factors involved in the pathogenesis of NPC accumulate.Glycoproteins are characterized by polymers of saccharides attached to the amino acid sequences of proteins during the process of glycosylation.They are present in all animal cells and are especially abundant on the surface of tumor cells.Alterations in expression of cellular glycoproteins have recently attracted attention as a key component of neoplastic progression.Tumor-associated glycoproteins may serve as a hallmark of cancer cells and thus represent novel diagnostic and even therapeutic targets.Interest in the role of glycoproteins in cancer in general and specifically in NPC pathology has steadily increased over the past fifty years,reaching over thousands and two hundred publications in the last five years,respectively.Here,data on a specific class of proteins,glycoproteins,involved in tumorigenesis of NPCs are summarized,with a focus on a few of the best-studied ones.Relevant studies performed mainly in the last five years were retrieved and collected through the PubMed system.
文摘During mammalian fertilisation, the zona pellucida （ZP） matrix surrounding the oocyte is responsible for the binding of the spermatozoa to the oocyte and induction of the acrosome reaction （AR） in the ZP-bound spermatozoon. The AR is crucial for the penetration of the ZP matrix by spermatozoa. The ZP matrix in mice is composed of three glycoproteins designated ZP1, ZP2 and ZP3, whereas in humans, it is composed of four （ZP1, ZP2, ZP3 and ZP4）. ZP3 acts as the putative primary sperm receptor and is responsible for AR induction in mice, whereas in humans （in addition to ZP3）, ZP1 and ZP4 also induce the AR. The ability of ZP3 to induce the AR resides in its C-terminal fragment. O-linked glycans are critical for the murine ZP3-mediated AR. However, N-linked glycans of human ZP1, ZP3 and ZP4 have important roles in the induction of the AR. Studies with pharmacological inhibitors showed that the ZP3-induced AR involves the activation of the Gi-coupled receptor pathway, whereas ZP1- and ZP4-mediated ARs are independent of this pathway. The ZP3-induced AR involves the activation of T-type voltage-operated calcium channels （VOCCs）, whereas ZP1- and ZP4-induced ARs involve both T- and L-type VOCCs. To conclude, in mice, ZP3 is primarily responsible for the binding of capacitated spermatozoa to the ZP matrix and induction of the AR, whereas in humans （in addition to ZP3）, ZP1 and ZP4 also participate in these stages of fertilisation.
文摘Aberrations in protein glycosylation and polysaccharides play a pivotal role in pancreatic tumorigenesis, influencing cancer progression, metastasis, immunoresponse and chemoresistance. Abnormal expression in sugar moieties can impact the function of various glycoproteins, including mucins, surface receptors, adhesive proteins, proteoglycans, as well as their effectors and binding ligands, resulting in an increase in pancreatic cancer invasiveness and a cancerfavored microenvironment. Recent advance in glycoproteomics, glycomics and other chemical biology techniques have been employed to better understand the complex mechanism of glycosylation events and how they orchestrate molecular activities in genomics, proteomics and metabolomics implicated in pancreatic adenocarcinoma. A variety of strategies have been demonstrated targeting protein glycosylation and polysaccharides for diagnostic and therapeutic development.
文摘Objective: To observe the effect of Xiaoyu Zhixue tablet (消瘀止血片,XYZXT) on the expression of platelet membrane glycoproteins in patients with hemorrhagic thrombopathy, and to explore its possible mechanism. Methods: The total of 148 patients with hemorrhagic thrombopathy were randomly divided into two groups, the traditional Chinese medicicne (TCM) group (n=98) treated with XYZXT and the Western medicine (WM) group (n=50) treated with adrenosin, vitamins C, K and P, both for 6 months. The therapeutic effect and the recovery rate of platelet aggregation in the two groups were observed. And platelet membrane glycoprotein (GP) Ⅰb/Ⅸ, GPⅡb/Ⅲa complexes, GPⅠb, GPⅡb, GP Ⅲa and P-selectin were analyzed by flow cytometry in both groups before and after treatment and also in 34 normal healthy subjects. Results: The total effective rate of hemostasis was 89. 8% in TCM group and 54. 0% in the WM group (x2=45.83, P<0.01), and the recovery rate of platelet aggregation was 72.4% and 4.0% respectively (x2=62.06, P<0.01). The fluorescence intensity of GP Ⅰ b/Ⅸ, GPⅡb/Ⅲa complexes, GPⅠb, GPⅢa and P-selectin were lower in both groups before treatment than those in the healthy subjects. Expression of above-mentioned marks was elevated in TCM group after 6 months' therapy, which was insignificantly different as compared with the healthy subjects (P>0.05) and higher than those in the WM group (P<0.05). Conclusion: One of the mechanisms in treating hemorrhagic thrombopathy with XYZXT is that it could regulate the expression of GP Ⅰb/Ⅸ, GPⅡ b/Ⅲa complexes, GPⅠb, GPⅢa and P-selectin at the level of receptor protein.
基金supported by the Natural Science Foundation of Jilin Provincial Science&Technology Department(No.20190201079JC)。
文摘The analysis of endogenous glycoproteins and glycopeptides in human body fluids is of great importance for screening and discovering disease biomarkers with clinical significance.However,the presence of interfering substances makes the direct quantitative detection of low-abundance glycoproteins and glycopeptides in human body fluids one of the great challenges in analytical chemistry.Magnetic solid phase extraction(MSPE)has the advantages of easy preparation,low cost and good magnetic responsiveness.Magnetic adsorbents are the core of MSPE technology,and magnetic adsorbents based on different functional materials are widely used in the quantitative analysis of glycoproteins and glycopeptides in human body fluids,making it possible to analyze glycoproteins and glycopeptides with low abundance as well as multiple types,which provides a technical platform for screening and evaluating glycoproteins and glycopeptides in body fluids as disease biomarkers.In this paper,we focus on the recent advances in the application of MSPE technology and magnetic adsorbents for the separation and enrichment of glycoproteins and glycopeptides in human body fluids,and the future trends and application prospects in this field are also presented.
文摘Early diagnosis of pregnancy plays an important role to minimize reproductive losses in farm animals.There are several methods for pregnancy diagnosis like profiling of reproductive hormones(such as progesterone and estrone sulfate),but sometimes they provide false-positive results.Embryo specific pregnancy markers,which delineate the presence and viability of the embryo,are considered as perfect for pregnancy determination.Pregnancy-associated glycoproteins are distinguished as the best indicator for the determination of early pregnancy,fetal number,and birth weight of kids.Pregnancy-associated glycoproteins are structurally correlated to aspartic proteinase and are communicated in the external epithelial cell layer of the placenta.They have been found to share about half amino acid sequence identity with pepsinogen,pepsin,cathepsin D and E.Dislike different individuals from aspartic proteinase family,numerous pregnancy-associated glycoproteins appear to be latent compound as a result of amino acid substitutions in and around the catalytic site.This review is to discuss the scope and prospects of pregnancy-associated glycoproteins as a pregnancy marker in farm animals,more specifically in goats.
文摘Chronic infection by either hepatitis B virus(HBV)or hepatitis C virus(HCV)share epidemiological characteristics with risks for development of severe complications such as liver cirrhosis and hepatocellular carcinoma.HBV and HCV also share a high genetic variability. Among highly variable regions,viral genes encoding surface proteins(hepatitis B surface antigen,E1/E2 HCV glycoproteins)play key roles in the stimulation of the host-related immune response and viral entry into hepatocytes.Specific segments of HBV envelope proteins(preS1,"a"determinant)are crucial in the entry process into permissive cells.HCV entry is a complex multistep process involving multiple cell cofactors (glycosaminoglycans,low density lipoprotein receptor, SR-B1,CD81,claudin-1,occludin,EGFR,EphA2)in the interaction with HCV E1/E2 envelope glycoproteins.In vitro both viruses can be controlled by antibody-me-diated neutralization targeting viral envelope,also essential in preventing HBV infection in vivo as observed through successful vaccination using HBs antigen.But preventive vaccination and/or therapeutic pressure can influence HBV and HCV variability.For HBV,the patterns of antiviral drug resistance in chronic hepatitis are complex and the original pol/S gene overlap has to be taken into account.Treatment-induced HBV mutations in pol could indeed generate S mutants with subsequent modified antigenicity or increased cancer induction.Variability of HBV and HCV envelope proteins combining high exposure to selective pressures and crucial functional roles require investigation in the context of diagnostic,vaccination and treatment tools.In this editorial a synthesis is performed of HBV and HCV envelope properties at the entry step and as antigenic proteins,and the subsequent clinical impact.
基金financially supported by the National Natural Science Foundation of China(Nos.21922402,21874017 and21727811)Liaoning Provincial Program for Promoting Talents(Nos.XLYC1807005 and XLYC1802016)the Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University,Ministry of Education,China,111 Project,No.B16009)。
文摘Discrimination of glycoproteins and cell types is a significant but difficult issue.Herein,we presented a novel fluorescence sensor array for the detection and identification of glycoproteins and cancer cells based on the specific affinity between boronic acid-containing carbon dots(BA-CDs)and cis-diol residues of polysaccharides.The differential binding affinity of three BA-CDs to various glycoproteins resulted in a different fluorescence turn-on signal pattern caused by aggregation-enhanced emission(AEE),along with negligible response from other proteins.Therefore,BA-CDs encompassing sensing elements and signal indicator into one can enable a fast and accurate discrimination of glycoproteins with simple and easy operation.Seven glycoproteins could be well discriminated at a very low concentration of 10 nmol/L.The discriminating capability of glycoproteins is not sacrificed in both human urine and serum.Notably,different glycoprotein compositions of cancer cells provide more recognizable features for identification of cancer cells,comparing to the total protein.Five cell types could be identified in 15 min at a low concentration of 1000 cells/mL.This method is fast,accurate,and easy operation,and has a potential application in cancer diagnosis.
基金support from the National Natural Science Foundation of China(No.21873101)is acknowledged。
文摘Antifreeze glycoproteins(AFGPs)facilitate the survival of various organisms in the polar region by preventing internal ice accumulation via an adsorption-inhibition mechanism.Inhibition of AFGP antifreeze activity by the borate buffers has been widely acknowledged as the direct experimental evidence supporting the hydroxyl,rather than methyl,binding mechanism.On the other hand,perturbation of borate binding on the AFGP configuration,which might have considerable influence on the binding efficiency of not only the hydroxyl but also the methyl groups,has rarely been quantitatively examined.Herein we studied,using molecular dynamics simulations,the perturbation on the configuration of a solvated AFGP8 protein induced by the binding of one single borate anion.Near the freezing point,this binding not only makes the disaccharide groups adjacent to the borate-binding disaccharide close to each other but also affects the entire AFGP8 conformation.The structural changes induced by the binding of borate on different disaccharide sidechains exhibit clear site-specificities and the effect of borate binding on the structural changes is significantly reduced at higher temperatures.Our study is valuable for further understanding the relationship between the structure and antifreeze activity of these antifreeze glycoproteins.
文摘Glycoproteins from tumor cells isolated by Con A, PHAE and RCAI, were coupled to horse radish peroxidase and then used as reporters to evaluate the oligosaccharides change on serum glycoproteins in digestive tract diseases and individual healthy persons. A value 2 standard deviation above the mean of the healthy person group was considered positive. The results indicated that the positive rates of the oligosaccharides bound with Con A, PHA-E and RCAI were 51 % (61/119) . 70. 6% (84/119) , and 76. 4% (91/119) in patients with gastric cancer: 53. 3% (16/30),46. 7% ( 14/30) and 66. 7% (20/30) in esophageal cancers; 28. 5% (15/49), 49. 0% (24/49) and .46. 9% (23/49) in colorectal cancer; 78. 1% (25/ 32) ,81. 3% (26/32) and 31. 3% (10/32) in gallbladder tumors; 60. 4% (29/48), 54. 1% (26/48) and 39. 5% (19/48) in hepatocellular cancer. The positive rates among the patients with benign diseases were also found to be 12. 7% (16/126), 15. 5% (20/126) and 26. 2% (33/126). However, the expression of the oligosaccharide moieties recognized by WGA on the glycoprotein bound with Con A, was significantly lower in the serum of patients with tumors than in those with benign disease and in healthy individuals (P<0. 01 , P<0. 01).
基金the National Natural Science Foundation of China (81473179 and 81673388)Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD, YX13200111)the funding for Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-PsychoDiseases (BM2013003)
文摘The glycosylation of proteins is responsible for their structural and functional roles in many cellular activities.This work describes a strategy that combines an efficient release, labeling and liquid chromatography–mass spectral analysis with the use of a comprehensive database to analyze N-glycans. The analytical method described relies on a recently commercialized kit in which quick deglycosylation is followed by rapid labeling and cleanup of labeled glycans. This greatly improves the separation, mass spectrometry（MS） analysis and fluorescence detection of N-glycans. A hypothetical database, constructed using Glyc Resoft, provides all compositional possibilities of N-glycans based on the common sugar residues found in N-glycans. In the initial version this database contains ＆gt; 8,700 N-glycans, and is compatible with MS instrument software and expandable. N-glycans from four different well-studied glycoproteins were analyzed by this strategy. The results provided much more accurate and comprehensive data than that had been previously reported. This strategy was then used to analyze the N-glycans present on the membrane glycoproteins of gastric carcinoma cells with different degrees of differentiation. Accurate and comprehensive N-glycan data from those cells was obtained efficiently and their differences were compared corresponding to their differentiation states. Thus, the novel strategy developed greatly improves accuracy, efficiency and comprehensiveness of N-glycan analysis.
文摘The authors carried out a steady and unsteady mass transfer studies to simulate both the release of proteins in physiologic environments and proteins transport through a tissue or organ from polymeric capsules by using a substance, the rhodamine B isothiocyanate dextran (RBID) that mimics the behaviour of glycoproteins such as vascular endothelial growth factor (VEFG). These studies highlighted the importance of electrostatic interactions between alginate and proteins in the release processes. Thereby, this fact has opened new perspectives in order to use these kind of capsules in protein recognition processes. The electrostatic interactions between alginate and RBID allow pH-dependent controlled release systems that simulate the behaviour of glycoproteins.
基金The authors would like to show deepest gratitude tothe Earmarked Fund for Jiangsu Agricultural Industry Technology System(JATS[2020]413)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX19_0682)forfinancial assistance.
文摘This study aimed to isolate and characterize the structures of glycoproteins from peas and determine their hypoglycemic activity.The crude pea glycoproteins(PGP)were extracted by hot water and purified by diethylaminoethyl(DEAE)-Sepharose chromatography and Sephadex G-100 size-exclusion chromatography in sequence.Then three main fractions were obtained,namely PGP1,PGP2 and PGP3,with molecular weights of 897615,846740 and 1194692 Da,respectively.The physical and chemical properties of the three fractions were evaluated and compared by Fourier transform infrared spectroscopy(FT-IR),nuclear magnetic resonance(NMR),scanning electron microscope(SEM),high performance liquid chromatography(HPLC)and other analytical techniques.The fraction PGP2 with the highest hypoglycemic activity,was screened using the Caco-2 monolayer cell model.It can inhibit the uptake of glucose in the small intestine,as well as the activities of maltase and sucrase.After simulated gastrointestinal digestion,PGP2 signifi cantly enhanced the inhibitory effect of α-glucosidase,and slightly reduced the inhibitory ability ofα-amylase.In summary,PGP2 possessed strong hypoglycemic activity after digestion.These results indicated that PGP2 has the potential to be developed into a functional food or natural medicine for the treatment of type 2 diabetes mellitus.
基金supported by the grants from the National Natural Science Foundation of China (Grant Nos. 31370191 and 31621061)Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB11030400)the National Key R&D Program of China (Grant No. 2018YFA0507200)
文摘Baculovirus can transduce a wide range of mammalian cells and is considered a promising gene therapy vector. However,the low transduction efficiency of baculovirus into many mammalian cells limits its practical application. Co-expressing heterologous viral glycoproteins(GPs), such as vesicular stomatitis virus G protein(VSV G), with baculovirus native envelope protein GP64 is one of the feasible strategies for improving virus transduction. Tick-borne thogotoviruses infect mammals and their GPs share sequence/structure homology and common evolutionary origins with baculovirus GP64.Herein, we tested whether thogotovirus GPs could facilitate the entry of the prototype baculovirus Autographa californica multiple multiple nucleopolyhedrovirus(AcMNPV) into mammalian cells. The gp genes of two thogotoviruses, Thogoto virus and Dhori virus, were inserted into the AcMNPV genome. Both GPs were properly expressed and incorporated into the envelope of the recombinant AcMNPVs. The transduction rates of recombinant AcMNPVs expressing the two thogotovirus GPs increased for approximately 4–12 fold compared to the wild type AcMNPV in six of the 12 tested mammalian cell lines. It seemed that thogotovirus GPs provide the recombinant AcMNPVs with different cell tropisms and showed better performance in several mammalian cells compared to VSV G incorporated AcMNPV. Further studies showed that the improved transduction was a result of augmented virus-endosome fusion and endosome escaping, rather than increased cell binding or internalization. We found the AcMNPV envelope protein GP64-mediated fusion was enhanced by the thogotovirus GPs at relatively higher p H conditions. Therefore, the thogotovirus GPs represent novel candidates to improve baculovirus-based gene delivery vectors.
基金supported by grants from the National Natural Science Foundation of China(Grant No.21205088)973 Project(Grant No.2011CB933100)+2 种基金National Science Fund for Distinguished Young Scholars(Grant No.81125019)Doctoral Research Fund from the Ministry of Education of China(Grant No.20121202120001)sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Objective： Hepatocellular carcinoma （HCC） is a leading cause of cancer-related deaths. Novel serum biomarkers are required to increase the sensitivity and specificity of serum screening for early HCC diagnosis. This study employed a quantitative proteomic strategy to analyze the differential expression of serum glycoproteins between HCC and normal control serum samples. Methods： Lectin affinity chromatography （LAC） was used to enrich glycoproteins from the serum samples. Quantitative mass spectrometric analysis combined with stable isotope dimethyl labeling and 2D liquid chromatography （LC） separations were performed to examine the differential levels of the detected proteins between HCC and control serum samples. Western blot was used to analyze the differential expression levels of the three serum proteins. Results： A total of 2,280 protein groups were identified in the serum samples from HCC patients by using the 2D LC-MS/MS method. Up to 36 proteins were up-regulated in the HCC serum, whereas 19 proteins were down-regulated. Three differential glycoproteins, namely, fibrinogen gamma chain （FGG）, FOS-like antigen 2 （FOSL2）, and a-l, 6-mannosylglycoprotein 6-^-N-acetylglucosaminyltransferase B （MGATSB） were validated by Western blot. All these three proteins were up-regulated in the HCC serum samples. Conclusion： A quantitative glycoproteomic method was established and proven useful to determine potential novel biomarkers for HCC.
基金funded by the National Natural Science Foundation of China (31360597 and 31160493)the doctoral fund project of Ministry of Education (20111515110008)Inner Mongolia technology application research project (20130224)
文摘Endogenous retroviruses(ERVs) are a component of the vertebrate genome and originate from exogenous infections of retroviruses in the germline of the host. ERVs have coevolved with their hosts over millions of years. Envelope glycoproteins of endogenous retroviruses are often expressed in the mammalian placenta, and their potential function has aroused considerable research interest, including the manipulation of maternal physiology to benefit the fetus. In most mammalian species, trophoblast fusion in the placenta is an important event, involving the formation of a multinucleated syncytiotrophoblast layer to fulfill essential fetomaternal exchange functions. The key function in this process derives from the envelope genes of endogenous retroviruses, namely syncytins, which show fusogenic properties and placenta-specific expression. This review discusses the important role of the recognized endogenous retrovirus envelope glycoproteins in the mammalian placenta.
基金support from the National High Technology Research and Development Program of China (No.2006AA09Z438)
文摘In order to select an optimum extraction method for the target glycoprotein （TGP） from jellyfish （Rhopilema esculentum） oral-arms, a high performance liquid chromatography （HPLC）-assay for the determination of the TGP was developed Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear （r= 0.9984, y=4.5895x＋47.601） over concentrations ranging from 50 to 400mgL^-1. The mean extraction recovery was 97.84% （CV2.60%）. The fractions containing TGP were isolated from jellyfish （R esculentum） oral-arms by four extraction methods： 1） water extraction （WE）, 2） phosphate buffer solution （PBS） extraction （PE）, 3） ultrasound-assisted water extraction （UA-WE）, 4） ultrasound-assisted P/3S extraction （UA-PE）. The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL （7.8 mm×300 ram） column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.
基金supported by the National Natural Science Foundation of China (No. 31125003 and No. 31321001)the Basic Work Program of the Ministry of Science and Technology of China (2013FY113500)
文摘Ebolaviruses are highly dangerous pathogens exhibiting extreme virulence in humans and nonhuman primates. The majority of ebolavirus species, most notably Zaire ebolavirus, can cause Ebola virus disease(EVD), formerly known as Ebola hemorrhagic fever, in humans. EVD is associated with case-fatality rates as high as 90%, and there is currently no specific treatment or licensed vaccine available against EVD. Understanding the molecular biology and pathogenesis of ebolaviruses is important for the development of antiviral therapeutics. Ebolavirus encodes several forms of glycoproteins(GPs), which have some interesting characteristics, including the transcriptional editing coding strategy and extensive O-glycosylation modification, clustered in the mucin-like domain of GP1, full-length GP(GP_(1,2)), and shed GP. In addition to the canonical role of the spike protein, GP_(1,2), in viral entry, ebolavirus GPs appear to have multiple additional functions,likely contributing to the complex pathogenesis of the virus. Here, we review the roles of ebolavirus GPs in viral pathogenesis.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)and funded by the Ministry of Education,Korea(Grant No.:2021R1A6A1A03044296)This study was supported by the Chung-Ang University Graduate Research Scholarship in 2022.
文摘Sialylated N-glycan isomers withα2-3 orα2-6 linkage(s)have distinctive roles in glycoproteins,but are difficult to distinguish.Wild-type(WT)and glycoengineered(mutant)therapeutic glycoproteins,cytotoxic T lymphocyte-associated antigen-4-immunoglobulin(CTLA4-Ig),were produced in Chinese hamster ovary cell lines;however,their linkage isomers have not been reported.In this study,N-glycans of CTLA4-Igs were released,labeled with procainamide,and analyzed by liquid chromatography-tandem mass spectrometry(MS/MS)to identify and quantify sialylated N-glycan linkage isomers.The linkage isomers were distinguished by comparison of 1)intensity of the N-acetylglucosamine ion to the sialic acid ion(Ln/Nn)using different fragmentation stability in MS/MS spectra and 2)retention time-shift for a selective m/z value in the extracted ion chromatogram.Each isomer was distinctively identified,and each quantity(>0.1%)was obtained relative to the total N-glycans(100%)for all observed ionization states.Twenty sialylated N-glycan isomers with onlyα2-3 linkage(s)in WT were identified,and each isomer's sum of quantities was 50.4%.Furthermore,39 sialylated N-glycan isomers(58.8%)in mono-(3 N-glycans;0.9%),bi-(18;48.3%),tri-(14;8.9%),and tetra-(4;0.7%)antennary structures of mutant were obtained,which comprised mono-(15 N-glycans;25.4%),di-(15;28.4%),tri-(8;4.8%),and tetra-(1;0.2%)sialylation,respectively,with onlyα2-3(10 N-glycans;4.8%),bothα2-3 andα2-6(14;18.4%),and onlyα2-6(15;35.6%)linkage(s).These results are consistent with those forα2-3 neuraminidase-treated N-glycans.This study generated a novel plot of Ln/Nn versus retention time to distinguish sialylated N-glycan linkage isomers in glycoprotein.
基金Acknowledgments This work was supported by grants to X.-L. Zhang from the National Natural Science Foundation of China （30870122, 30670098 and 20532020）, 973 Program of China 2006CB 504300 and 2009CB522507, National Grand Program on Key Infectious Disease （2008ZX10003-005）, Hubei Province Science Technology Department （2006ABD007, 2007ABC 010） and Hubei Ministry of Public Health of （JX1B074）.
文摘L-ficolin, one of lectin families, is a recently identified complement factor that initiates lectin pathway of complement. Little is known about its role in viral hepatitis. In the present study, we found that L-ficolin in serum from 103 patients with hepatitis C virus （HCV）, were significantly higher than that in 150 healthy controls. We further found that L-ficolin expressions were significantly increased in vitro study by HCV JFH-1 infected human hepatocyte cell line Huh7.5.1. Investigation of the mechanisms of the L-ficolin action on HCV demonstrated that L-ficolin protein could recognize and bind to envelope glycoproteins E1 and E2 of HCV, activating the lectin complement pathway-mediated cytolytic activity in HCV-infected hepatocyte. This interaction between L-ficolin and HCV E1 and E2 glycoproteins was attributed to the N-glycans of E1 and E2. These findings provide new insights into the biological functions of L-ficolin in clinically important hepatic viral diseases.
