Peptide-based therapeutics hold great promise for the treatment of various diseases;however,their clinical application is often hindered by toxicity challenges.The accurate prediction of peptide toxicity is crucial fo...Peptide-based therapeutics hold great promise for the treatment of various diseases;however,their clinical application is often hindered by toxicity challenges.The accurate prediction of peptide toxicity is crucial for designing safe peptide-based therapeutics.While traditional experimental approaches are time-consuming and expensive,computational methods have emerged as viable alternatives,including similarity-based and machine learning(ML)-/deep learning(DL)-based methods.However,existing methods often struggle with robustness and generalizability.To address these challenges,we propose HyPepTox-Fuse,a novel framework that fuses protein language model(PLM)-based embeddings with conventional descriptors.HyPepTox-Fuse integrates ensemble PLM-based embeddings to achieve richer peptide representations by leveraging a cross-modal multi-head attention mechanism and Transformer architecture.A robust feature ranking and selection pipeline further refines conventional descriptors,thus enhancing prediction performance.Our framework outperforms state-of-the-art methods in cross-validation and independent evaluations,offering a scalable and reliable tool for peptide toxicity prediction.Moreover,we conducted a case study to validate the robustness and generalizability of HyPepTox-Fuse,highlighting its effectiveness in enhancing model performance.Furthermore,the HyPepTox-Fuse server is freely accessible at https://balalab-skku.org/HyPepTox-Fuse/and the source code is publicly available at https://github.com/cbbl-skku-org/HyPepTox-Fuse/.The study thus presents an intuitive platform for predicting peptide toxicity and supports reproducibility through openly available datasets.展开更多
[Objectives]This study adopted a three-factor three-level orthogonal design to explore the effects of different application periods and methods of fish protein peptide on the fruit quality of‘Tieshanzha’.[Methods]Fa...[Objectives]This study adopted a three-factor three-level orthogonal design to explore the effects of different application periods and methods of fish protein peptide on the fruit quality of‘Tieshanzha’.[Methods]Factor A was set as the application period,with three levels:fruit-setting stage,core-hardening stage,and pre-coloring stage.Factor B was set as the application method,with three levels:root application,foliar spray,and root application+foliar spray.Factor C was set as the application concentration,with three levels:0,5 and 10 ml/L.[Results]Application period had an extremely significant effect on single fruit weight.Fertilization at the fruit-setting stage showed a single fruit weight as high as 13.36 g,which was 27.9%and 24%higher than those achieved by fertilization at the core-hardening stage and the pre-coloring stage,respectively.The factor that had the greatest impact on the internal quality of hawthorn fruit,specifically the Vc content,was application method.The optimal combination was foliar spray at the core-hardening stage with a concentration of 10 ml/L,which achieved the best fertilization effect.[Conclusions]This study provides a theoretical basis for improving fruit quality of‘Tieshanzha’.展开更多
Chemical modification of native peptides and proteins is a versatile strategy to facilitate late-stage diversification for functional studies.Among the proteogenic amino acids,lysine is extensively involved in posttra...Chemical modification of native peptides and proteins is a versatile strategy to facilitate late-stage diversification for functional studies.Among the proteogenic amino acids,lysine is extensively involved in posttranslational modifications and the binding of ligands to target proteins,making its selective modification attractive.However,lysine’s high natural abundance and solvent accessibility,as well as its relatively low reactivity to cysteine,necessitate addressing chemoselectivity and regioselectivity for the Lys modification of native proteins.Although Lys chemoselective modification methods have been well developed,achieving site-selective modification of a specific Lys residue remains a great challenge.In this review,we discussed the challenges of Lys selective modification,presented recent examples of Lys chemoselective modification,and summarized the currently known methods and strategies for Lys site-selective modification.We also included an outlook on potential solutions for Lys site-selective labeling and its potential applications in chemical biology and drug development.展开更多
Bioactive peptides and proteins(BAPPs)are promising therapeutic agents for tissue repair with considerable advantages,including multifunctionality,specificity,biocompatibility,and biodegradability.However,the high com...Bioactive peptides and proteins(BAPPs)are promising therapeutic agents for tissue repair with considerable advantages,including multifunctionality,specificity,biocompatibility,and biodegradability.However,the high complexity of tissue microenvironments and their inherent deficiencies such as short half-live and susceptibility to enzymatic degradation,adversely affect their therapeutic efficacy and clinical applications.Investigating the fundamental mechanisms by which BAPPs modulate the microenvironment and developing rational delivery strategies are essential for optimizing their administration in distinct tissue repairs and facilitating clinical translation.This review initially focuses on the mechanisms through which BAPPs influence the microenvironment for tissue repair via reactive oxygen species,blood and lymphatic vessels,immune cells,and repair cells.Then,a variety of delivery platforms,including scaffolds and hydrogels,electrospun fibers,surface coatings,assisted particles,nanotubes,two-dimensional nanomaterials,and nanoparticles engineered cells,are summarized to incorporate BAPPs for effective tissue repair,modification strategies aimed at enhancing loading efficiencies and release kinetics are also reviewed.Additionally,the delivery of BAPPs can be precisely regulated by endogenous stimuli(glucose,reactive oxygen species,enzymes,pH)or exogenous stimuli(ultrasound,heat,light,magnetic field,and electric field)to achieve on-demand release tailored for specific tissue repair needs.Furthermore,this review focuses on the clinical potential of BAPPs in facilitating tissue repair across various types,including bone,cartilage,intervertebral discs,muscle,tendons,periodontal tissues,skin,myocardium,nervous system(encompassing brain,spinal cord,and peripheral nerve),endometrium,as well as ear and ocular tissue.Finally,current challenges and prospects are discussed.展开更多
Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv...Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.展开更多
The preparation of specifically iodine-125 (125I)-labeled peptides of high purity and specific activity represents a key tool for the detailed characterization of their binding properties in interaction with their bin...The preparation of specifically iodine-125 (125I)-labeled peptides of high purity and specific activity represents a key tool for the detailed characterization of their binding properties in interaction with their binding partners. Early synthetic methods for the incorporation of iodine faced challenges such as harsh reaction conditions, the use of strong oxidants and low reproducibility. Herein, we review well-established radiolabeling strategies available to incorporate radionuclide into a protein of interest, and our long-term experience with a mild, simple and generally applicable technique of 125I late-stage-labeling of biomolecules using the Pierce iodination reagent for the direct solid-phase oxidation of radioactive iodide. General recommendations, tips, and details of optimized chromatographic conditions to isolate pure, specifically 125I-mono-labeled biomolecules are illustrated on a diverse series of (poly)peptides, ranging up to 7.6 kDa and 67 amino acids (aa). These series include peptides that contain at least one tyrosine or histidine residue, along with those featuring disulfide crosslinking or lipophilic derivatization. This mild and straightforward late-stage-labeling technique is easily applicable to longer and more sensitive proteins, as demonstrated in the cases of the insulin-like growth factor binding protein-3 (IGF-BP-3) (29 kDa and 264 aa) and the acid-labile subunit (ALS) (93 kDa and 578 aa).展开更多
Pentatricopeptide repeat(PPR)proteins perform essential functions in post-transcriptional regulation of gene expression,particularly RNA editing and RNA splicing,in plant organelles.Although research on chloroplast bi...Pentatricopeptide repeat(PPR)proteins perform essential functions in post-transcriptional regulation of gene expression,particularly RNA editing and RNA splicing,in plant organelles.Although research on chloroplast biogenesis and development has been extensive,the functions of most PPR genes in this process in rice(Oryza sativa)remain incompletely understood.This study identifies a novel P-type PPR protein,YELLOW-GREEN LEAF AND SEEDLING LETHALITY(YGS),which localizes to rice chloroplasts.YGS shows predominant expression in leaves.The ygs mutants,generated through CRISPR/Cas9-mediated genome editing of the YGS gene,displayed yellow-green leaves and seedling lethality.These phenotypes corresponded with reduced pigment levels and disrupted chloroplast ultrastructure compared to wild-type plants.Furthermore,the expression of genes associated with chloroplast development and chlorophyll biosynthesis showed significant alterations in the ygs mutants.The absence of YGS function affected RNA editing of rpl2 and intron splicing of ycf3-1 in the plastid genome.Additionally,YGS demonstrated interaction with the chloroplast signal recognition particle protein Oscp SRP54b in yeast two-hybrid and bimolecular fluorescence complementation analyses.These results indicate that YGS participates in RNA editing and RNA splicing in chloroplasts,thus serving a vital role in rice chloroplast development.展开更多
By investigating 17 peptide arylthioesters that were previously challenging to produce,this study reveals a clear correlation between increased ligation activity and decreased pKa values of their corresponding arylthi...By investigating 17 peptide arylthioesters that were previously challenging to produce,this study reveals a clear correlation between increased ligation activity and decreased pKa values of their corresponding arylthiols.The observed differences are attributed to variations in thioester bond strength and steric hindrance.These insights have led to the development of an improved one-pot chemical protein synthesis approach that leverages the reactivity differences between peptide arylthioesters with C-terminal Ala-SPh(4-NO_(2))and Ala-S-Ph(2,6-diCH_(3)).This approach eliminates the need for thiol-thioester exchange and additive removal steps while enabling in situ desulfurization,thereby significantly simplifying the protein synthesis process.展开更多
Chloroplasts are essential for normal plant growth and development.In plants,pentatricopeptide repeat(PPR)proteins mediate RNA processing in chloroplasts.Here,we characterized a rice albino leaf 5(al5)mutant which exh...Chloroplasts are essential for normal plant growth and development.In plants,pentatricopeptide repeat(PPR)proteins mediate RNA processing in chloroplasts.Here,we characterized a rice albino leaf 5(al5)mutant which exhibits albinism during early leaf development.The MutMap+analysis and transformation experiments revealed that AL5 encodes a chloroplast-localized P-type PPR protein.The AL5 mutation resulted in the defective splicing of ribosomal protein L2(rpl2)and ribosomal protein S12(rps12),which are involved in the synthesis of chloroplast 50S and 30S ribosomal subunits,respectively.The RNA-electrophoretic mobility shift assay(REMSA)further demonstrated that AL5 directly binds to rpl2 transcripts.Finally,disruption of AL5 led to reduced expression of plastid-encoded polymerase(PEP)-dependent plastid genes and nuclear-encoded photosynthetic genes.Notably,the albino al5 mutant phenotype was regulated by low temperature.These results suggest that AL5 participates in plastid RNA splicing and plays an important role in chloroplast development in rice.展开更多
Peptide and protein drugs with therapeutic effects suffer from their short half-life and low stability,albeit their high efficiency and specificity.To overcome these demerits,long-acting drug delivery systems have bee...Peptide and protein drugs with therapeutic effects suffer from their short half-life and low stability,albeit their high efficiency and specificity.To overcome these demerits,long-acting drug delivery systems have been developed,wherein poly(lactic-co-glycolic acid)(PLGA)implants are most preferred owing to their excellent biodegradability and biocompatibility.Dozens of PLGA based products have been approved since1986,when the first product,named Decapeptyl R,successfully marched into market.To meet the increasing demand for delivering various peptides and proteins,different kinds of technologies have been developed for lab-scale fabrication or industrial manufacture.This review aims to introduce recent advances of PLGA implants,and give a brief summary of fundamental properties of PLGA,fabrication technologies of peptides/proteins-loaded PLGA implants as well as factors influencing the drug release processes.Moreover,challenges and future perspectives are also highlighted.展开更多
Recent years have witnessed growing interest in the role of peptides in animal nutrition. Chemical, enzymatic, or microbial hydrolysis of proteins in animal by-products or plant-source feedstuffs before feeding is an ...Recent years have witnessed growing interest in the role of peptides in animal nutrition. Chemical, enzymatic, or microbial hydrolysis of proteins in animal by-products or plant-source feedstuffs before feeding is an attractive means of generating high-quality small or large peptides that have both nutritional and physiological or regulatory functions in livestock, poultry and fish. These peptides may also be formed from ingested proteins in the gastrointestinal tract, but the types of resultant peptides can vary greatly with the physiological conditions of the animals and the composition of the diets. In the small intestine, large peptides are hydrolyzed to small peptides,which are absorbed into enterocytes faster than free amino acids（AAs） to provide a more balanced pattern of AAs in the blood circulation. Some peptides of plant or animal sources also have antimicrobial, antioxidant,antihypertensive, and immunomodulatory activities. Those peptides which confer biological functions beyond their nutritional value are called bioactive peptides. They are usually 2–20 AA residues in length but may consist of 〉20AA residues. Inclusion of some（e.g. 2–8%） animal-protein hydrolysates（e.g., porcine intestine, porcine mucosa,salmon viscera, or poultry tissue hydrolysates） or soybean protein hydrolysates in practical corn-and soybean mealbased diets can ensure desirable rates of growth performance and feed efficiency in weanling pigs, young calves,post-hatching poultry, and fish. Thus, protein hydrolysates hold promise in optimizing the nutrition of domestic and companion animals, as well as their health（particularly gut health） and well-being.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
Peptide stapling strategy has been proven a promising solution in addressing two major pharmacological hurdles, proteolytic stability and membrane permeability, for small peptides as therapeutics. This stapling peptid...Peptide stapling strategy has been proven a promising solution in addressing two major pharmacological hurdles, proteolytic stability and membrane permeability, for small peptides as therapeutics. This stapling peptides feature a covalent cross-link of side chains, thus effectively mimicking α-helix as inhibitors of protein-protein interactions. In this review, we category and analyze key examples of various peptide stapling strategies based on different cross-links aligned on the side chain of peptides mainly in the last three years.展开更多
Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen so...Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen source for nourishment.They are mainly transported by oligopeptide transporter-1(PepT-1)which are primarily expressed in the intestine with the characteristics of high-capacity and low energy consumption.Our preliminary research discovered the transmembrane transport of SLN could be improved by stimulating the oligopeptide absorption pathway.This implied the potential of combining the advantages of SLN with oligopeptide transporter mediated transportation.Herein,two kinds of dipeptide modified SLN were designed with insulin and glucagon like peptide-1(GLP-1)analogue exenatide as model drugs.These drugs loaded SLN showed enhanced oral bioavailability and hypoglycemic effect in both type I diabetic C57BL/6mice and type II diabetic KKAymice.Compared with un-modified SLN,dipeptide-modified SLN could be internalized by intestinal epithelial cells via PepT-1-mediated endocytosis with higher uptake.Interestingly,after internalization,more SLN could access the systemic circulation via lymphatic transport pathway,highlighting the potential to combine the oligopeptide-absorption route with SLN for oral drug delivery.展开更多
Banana bunchy top virus(BBTV)poses a serious danger to banana crops worldwide.BBTV-encoded protein B4 is a determinant of pathogenicity.However,the relevant molecular mechanisms underlying its effects remain unknown.I...Banana bunchy top virus(BBTV)poses a serious danger to banana crops worldwide.BBTV-encoded protein B4 is a determinant of pathogenicity.However,the relevant molecular mechanisms underlying its effects remain unknown.In this study,we found that a functional peptide could be liberated from protein B4,likely via proteolytic processing.Site-directed mutagenesis indicated that the functional processing of protein B4 is required for its pathogenic effects,including dwarfism and sterility,in plants.The released protein fragment targets host proteins,such as the large subunit of RuBisCO(RbcL)and elongation factor 2(EF2),involved in protein synthesis.Therefore,the peptide released from B4(also a precursor)may act as a non-canonical modifier to influence host-pathogen interactions involving BBTV and plants.展开更多
Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with ...Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with traditional pharmaceuticals while delivering superior anxiolytic and antidepressant effects.This review summarizes current research on food-derived anxiolytic and antidepressant protein hydrolysates and peptides,and subsequently analyses their physicochemical characteristics and elaborates on their mechanisms.The aim of this work is to contribute to the in-depth study and provide a theoretical foundation for the development of related products to better serve patients with anxiety and depression.展开更多
Functional chloroplast generation depends on the precise coordination of gene expression between the plastid and the nucleus and is essential for plant growth and development. In this study, a rice（Oryza sativa） mut...Functional chloroplast generation depends on the precise coordination of gene expression between the plastid and the nucleus and is essential for plant growth and development. In this study, a rice（Oryza sativa） mutant that exhibited albino and seedling-lethal phenotypes was isolated from a60Co-irradiated rice population. The mutant gene was identified as an ortholog of the Arabidopsis plastid transcriptionally active chromosome protein 2（p TAC2） gene, and the mutant strain was designated osptac2. Sequence and transcription analyses showed that Osp TAC2 encodes a putative chloroplast protein consisting of 10 pentratricopeptide repeat（PPR） domains and a C-terminal small Mut S-related（SMR） domain. Cytological observations via microscopy showed that the Osp TAC2-green fluorescent fusion protein is localized in the chloroplasts. Transmission electron microscopy revealed that the chloroplast of the osptac2 mutant lacks an organized thylakoid membrane. The transcript levels of all investigated PEP（plastid-encoded RNA polymerase）-dependent genes were dramatically reduced in the osptac2 mutant, whereas the transcript levels of NEP（nuclear-encoded polymerase）-dependent genes were increased. These results suggest that Osp TAC2 plays a critical role in chloroplast development and indicate that the molecular function of the Osp TAC2 gene is conserved in rice and Arabidopsis.展开更多
BACKGROUND: The development of a harmless and effi- cient nonviral gene delivery system that can facilitate the penetration of nucleic acids through the plasma membrane is a key to successful gene therapy. The aim of ...BACKGROUND: The development of a harmless and effi- cient nonviral gene delivery system that can facilitate the penetration of nucleic acids through the plasma membrane is a key to successful gene therapy. The aim of this study was to test a nonviral gene transferring vector's function of delivering DNA into liver cells to provide an important clue for gene transfer in liver gene therapy. METHODS: The complex of DNA and DNA delivering protein was injected into mice through their tail veins. Then the mice were killed and their liver tissue was sec- tioned. The gene transferring results were detected using a confocal laser scanning microscope. RESULTS: Fluorescence analysis indicated that both DNA- membrane penetrating peptide (MPP) complex and DNA- hepatocyte specific receptor binding domain ( HSRBD) - MPP complex could go into liver cells. The fluorescence value of liver cells in the DNA-HSRBD-MPP group was higher than that in the DNA-MPP group. CONCLUSIONS; MPP can successfully deliver DNA and protein into cells, and MPP with a HSRBD can specifically deliver DNA into liver cells. These have laid a foundation for further study on the nonviral liver cell gene delivering system.展开更多
Objective:To understand the role of ANP mRNA transcription regulation in gpl30-mediated cardiomyocyte hypertrophy,and the involved mitogen-aetivated protein kinase kinase(MEK)-extracellular signal-regulated kinase(ERK...Objective:To understand the role of ANP mRNA transcription regulation in gpl30-mediated cardiomyocyte hypertrophy,and the involved mitogen-aetivated protein kinase kinase(MEK)-extracellular signal-regulated kinase(ERK,also called p42/p44 MAPK)signaling pathway.Methods:isolated neonatal ventricular myocytes were treated with different concentrations of CT-1(10^(-9),10^(-8)and 10^(-7)mol/L).MTT was used to analyze the viability and RT-PCR was used to detect ANP mRNA levels in eardiomyocyte.To inhibit p42/p44 MAPK activity in hypertrophic cardiomyoeytes,the cells were pretreated with a specific MEKI inhibitor.Results:CT-1significantly induced ANP mRNA expression and the viability of canliomyocytes in a doseand time-dependent manner.Furthermore,blocking p42/p44 MAPK activity by the special MEk1 inhibitor uprcgulatcd the ANP mKNA.Conclusions:p42/p44 MAPK have an important role in suppressing ANP mRNA transcription and cell activity in gpl30-mediated hypertrophic ventricular myocytes.展开更多
AIM:To purify the heat shock protein (HSP) 70-associated tumor peptides and to observe its non-MHC-I molecule restrictive antitumor effect.METHODS:By ConA-sepharose affinity chromatography,ADP-agarose affinity chromat...AIM:To purify the heat shock protein (HSP) 70-associated tumor peptides and to observe its non-MHC-I molecule restrictive antitumor effect.METHODS:By ConA-sepharose affinity chromatography,ADP-agarose affinity chromatography, and DEAE anion exchange chromatography, we were able to purify HSP70-associated peptides from mouse hepatoma (HCaF) cells treated in heat shock at 42℃. Specific active immunization and adoptive cellular immunization assay were adopted to observe the immunoprotective effect elicited by HSP70-associated peptide complexes isolated from HcaF.RESULTS: The finally purified HSP-associated peptides had a very high purity and specificity found by SDS-PAGE and Western blot. Mice immunized with HSP70-associated peptide complexes purified from HCaF cells were protected from HCaF living cell challenge. This effect was dose dependent.Adoptive immunization of immune spleen cells of mice immunized with HSP70-associated peptide complexes could elicit immunity against HCaF challenge, and the tumor-free mice could resist repeated challenges. This effect could be continuously enhanced by repeated challenge with HCaF living cells. The tumor-free mice could tolerate the challenge for as high as 1×10^7 HCaF cells. The mice immunized once with spleen cells pulsed with HSP70-associated peptide complexes in vitro could also result in a certain adoptive immunity against HCaF.CONCLUSION:High purity and specificity of HSP70-associated peptides could be achieved from tumor cells by the low-pressure affinity chromatography method used in this study. HSP70-associated peptide complexes derived from the HCaF can elicit non-MHC-I molecule restrictive immunoprotective effect against HCaF.This effect can be transferred by adoptive immunization to mice and enhanced by repeated challenge with HCaF live cells.展开更多
基金supported by the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT,Republic of Korea(Grant No.:RS-2024-00344752)supported by the Department of Integrative Biotechnology,Sungkyunkwan University(SKKU)and the BK21 FOUR Project,Republic of Korea.
文摘Peptide-based therapeutics hold great promise for the treatment of various diseases;however,their clinical application is often hindered by toxicity challenges.The accurate prediction of peptide toxicity is crucial for designing safe peptide-based therapeutics.While traditional experimental approaches are time-consuming and expensive,computational methods have emerged as viable alternatives,including similarity-based and machine learning(ML)-/deep learning(DL)-based methods.However,existing methods often struggle with robustness and generalizability.To address these challenges,we propose HyPepTox-Fuse,a novel framework that fuses protein language model(PLM)-based embeddings with conventional descriptors.HyPepTox-Fuse integrates ensemble PLM-based embeddings to achieve richer peptide representations by leveraging a cross-modal multi-head attention mechanism and Transformer architecture.A robust feature ranking and selection pipeline further refines conventional descriptors,thus enhancing prediction performance.Our framework outperforms state-of-the-art methods in cross-validation and independent evaluations,offering a scalable and reliable tool for peptide toxicity prediction.Moreover,we conducted a case study to validate the robustness and generalizability of HyPepTox-Fuse,highlighting its effectiveness in enhancing model performance.Furthermore,the HyPepTox-Fuse server is freely accessible at https://balalab-skku.org/HyPepTox-Fuse/and the source code is publicly available at https://github.com/cbbl-skku-org/HyPepTox-Fuse/.The study thus presents an intuitive platform for predicting peptide toxicity and supports reproducibility through openly available datasets.
基金Supported by Key Research and Development Program of Hebei Province(23317102D).
文摘[Objectives]This study adopted a three-factor three-level orthogonal design to explore the effects of different application periods and methods of fish protein peptide on the fruit quality of‘Tieshanzha’.[Methods]Factor A was set as the application period,with three levels:fruit-setting stage,core-hardening stage,and pre-coloring stage.Factor B was set as the application method,with three levels:root application,foliar spray,and root application+foliar spray.Factor C was set as the application concentration,with three levels:0,5 and 10 ml/L.[Results]Application period had an extremely significant effect on single fruit weight.Fertilization at the fruit-setting stage showed a single fruit weight as high as 13.36 g,which was 27.9%and 24%higher than those achieved by fertilization at the core-hardening stage and the pre-coloring stage,respectively.The factor that had the greatest impact on the internal quality of hawthorn fruit,specifically the Vc content,was application method.The optimal combination was foliar spray at the core-hardening stage with a concentration of 10 ml/L,which achieved the best fertilization effect.[Conclusions]This study provides a theoretical basis for improving fruit quality of‘Tieshanzha’.
基金the National Natural Science Foundation of China(Nos.82373722,22077144)Hunan Provincial Natural Science Foundation of China(No.2023JJ30527)+2 种基金Guangdong Basic and Applied Basic Research Foundation(No.2023B1515040006)Guangdong Provincial Key Laboratory of Construction Foundation(No.2023B1212060022)Key Research and Development Program of Guangdong Province(No.2020B1111110003).
文摘Chemical modification of native peptides and proteins is a versatile strategy to facilitate late-stage diversification for functional studies.Among the proteogenic amino acids,lysine is extensively involved in posttranslational modifications and the binding of ligands to target proteins,making its selective modification attractive.However,lysine’s high natural abundance and solvent accessibility,as well as its relatively low reactivity to cysteine,necessitate addressing chemoselectivity and regioselectivity for the Lys modification of native proteins.Although Lys chemoselective modification methods have been well developed,achieving site-selective modification of a specific Lys residue remains a great challenge.In this review,we discussed the challenges of Lys selective modification,presented recent examples of Lys chemoselective modification,and summarized the currently known methods and strategies for Lys site-selective modification.We also included an outlook on potential solutions for Lys site-selective labeling and its potential applications in chemical biology and drug development.
基金supported by the National Natural Science Foundation of China(82372405,81871752)the Key Research and Development Program of Hubei Province(2022BCA052)+2 种基金the Key Research and Development Program of Wuhan City(2024020702030105)the Fundamental Research Funds for the Central Universities(2042023kf0199)the Translational Medicine and Interdisciplinary Research Joint Fund of Zhongnan Hospital of Wuhan University(ZNJC202014).
文摘Bioactive peptides and proteins(BAPPs)are promising therapeutic agents for tissue repair with considerable advantages,including multifunctionality,specificity,biocompatibility,and biodegradability.However,the high complexity of tissue microenvironments and their inherent deficiencies such as short half-live and susceptibility to enzymatic degradation,adversely affect their therapeutic efficacy and clinical applications.Investigating the fundamental mechanisms by which BAPPs modulate the microenvironment and developing rational delivery strategies are essential for optimizing their administration in distinct tissue repairs and facilitating clinical translation.This review initially focuses on the mechanisms through which BAPPs influence the microenvironment for tissue repair via reactive oxygen species,blood and lymphatic vessels,immune cells,and repair cells.Then,a variety of delivery platforms,including scaffolds and hydrogels,electrospun fibers,surface coatings,assisted particles,nanotubes,two-dimensional nanomaterials,and nanoparticles engineered cells,are summarized to incorporate BAPPs for effective tissue repair,modification strategies aimed at enhancing loading efficiencies and release kinetics are also reviewed.Additionally,the delivery of BAPPs can be precisely regulated by endogenous stimuli(glucose,reactive oxygen species,enzymes,pH)or exogenous stimuli(ultrasound,heat,light,magnetic field,and electric field)to achieve on-demand release tailored for specific tissue repair needs.Furthermore,this review focuses on the clinical potential of BAPPs in facilitating tissue repair across various types,including bone,cartilage,intervertebral discs,muscle,tendons,periodontal tissues,skin,myocardium,nervous system(encompassing brain,spinal cord,and peripheral nerve),endometrium,as well as ear and ocular tissue.Finally,current challenges and prospects are discussed.
基金supported by the Natural Science Foundation of Shandong Province,No.ZR2023MC168the National Natural Science Foundation of China,No.31670989the Key R&D Program of Shandong Province,No.2019GSF107037(all to CS).
文摘Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.
基金Institutional support was provided by the project of the Czech Academy of Sciences,Czech Republic(to the Institute of Organic Chemistry and Biochemistry)(Project No.:RVO 61388963)This work was supported by the project National Institute for Research of Metabolic and Cardiovascular Diseases(Programme EXCELES)funded by the European Union's Next Generation EU(Project No.:LX22NPO5104)the Czech Science Foundation,Czech Republic(Grant No.:23-05805S).
文摘The preparation of specifically iodine-125 (125I)-labeled peptides of high purity and specific activity represents a key tool for the detailed characterization of their binding properties in interaction with their binding partners. Early synthetic methods for the incorporation of iodine faced challenges such as harsh reaction conditions, the use of strong oxidants and low reproducibility. Herein, we review well-established radiolabeling strategies available to incorporate radionuclide into a protein of interest, and our long-term experience with a mild, simple and generally applicable technique of 125I late-stage-labeling of biomolecules using the Pierce iodination reagent for the direct solid-phase oxidation of radioactive iodide. General recommendations, tips, and details of optimized chromatographic conditions to isolate pure, specifically 125I-mono-labeled biomolecules are illustrated on a diverse series of (poly)peptides, ranging up to 7.6 kDa and 67 amino acids (aa). These series include peptides that contain at least one tyrosine or histidine residue, along with those featuring disulfide crosslinking or lipophilic derivatization. This mild and straightforward late-stage-labeling technique is easily applicable to longer and more sensitive proteins, as demonstrated in the cases of the insulin-like growth factor binding protein-3 (IGF-BP-3) (29 kDa and 264 aa) and the acid-labile subunit (ALS) (93 kDa and 578 aa).
基金supported by the National Natural Science Foundation of China(32201784,32072048,and U2004204)the Natural Science Foundation of Shandong Province,China(ZR2020QC111 and ZR2022QC176)the Talent Introduction Project of Dezhou University,China(2020xjrc207)。
文摘Pentatricopeptide repeat(PPR)proteins perform essential functions in post-transcriptional regulation of gene expression,particularly RNA editing and RNA splicing,in plant organelles.Although research on chloroplast biogenesis and development has been extensive,the functions of most PPR genes in this process in rice(Oryza sativa)remain incompletely understood.This study identifies a novel P-type PPR protein,YELLOW-GREEN LEAF AND SEEDLING LETHALITY(YGS),which localizes to rice chloroplasts.YGS shows predominant expression in leaves.The ygs mutants,generated through CRISPR/Cas9-mediated genome editing of the YGS gene,displayed yellow-green leaves and seedling lethality.These phenotypes corresponded with reduced pigment levels and disrupted chloroplast ultrastructure compared to wild-type plants.Furthermore,the expression of genes associated with chloroplast development and chlorophyll biosynthesis showed significant alterations in the ygs mutants.The absence of YGS function affected RNA editing of rpl2 and intron splicing of ycf3-1 in the plastid genome.Additionally,YGS demonstrated interaction with the chloroplast signal recognition particle protein Oscp SRP54b in yeast two-hybrid and bimolecular fluorescence complementation analyses.These results indicate that YGS participates in RNA editing and RNA splicing in chloroplasts,thus serving a vital role in rice chloroplast development.
基金CAMS Innovation Fund for Medical Sciences(CIFMS,No.2021-I2M-1-026)the National Key R&D Program of China(No.2018YFE0111400)+6 种基金the NIH Research Project Grant Program(No.R01 EB025892)the National Natural Science Foundation of China(the Training Program of the Major Research Plan,No.91853120)the National Major Scientific and Technological Special Project of China(Nos.2018ZX09711001-005 and 2018ZX09711001-013)the State Key Laboratory of Bioactive Substance and Function of Natural Medicines,Institute of Materia Medicathe Biomedical High Performance Computing Platform,Chinese Academy of Medical Sciencesthe Chinese Academy of Medical SciencesPeking Union Medical College for funding and support.
文摘By investigating 17 peptide arylthioesters that were previously challenging to produce,this study reveals a clear correlation between increased ligation activity and decreased pKa values of their corresponding arylthiols.The observed differences are attributed to variations in thioester bond strength and steric hindrance.These insights have led to the development of an improved one-pot chemical protein synthesis approach that leverages the reactivity differences between peptide arylthioesters with C-terminal Ala-SPh(4-NO_(2))and Ala-S-Ph(2,6-diCH_(3)).This approach eliminates the need for thiol-thioester exchange and additive removal steps while enabling in situ desulfurization,thereby significantly simplifying the protein synthesis process.
基金supported by the Open Competition Program of Top Ten Critical Priorities of Agricultural Science and Technology Innovation for the 14th Five-Year Plan of Guangdong Province(2022SDZG05)the Guangdong Province Rural Revitalization Strategy Special Fund Seed Industry Revitalization Project(2022-NJS-15-001)the Key-Area Research and Development Program of Guangdong Province(2022B0202060005).
文摘Chloroplasts are essential for normal plant growth and development.In plants,pentatricopeptide repeat(PPR)proteins mediate RNA processing in chloroplasts.Here,we characterized a rice albino leaf 5(al5)mutant which exhibits albinism during early leaf development.The MutMap+analysis and transformation experiments revealed that AL5 encodes a chloroplast-localized P-type PPR protein.The AL5 mutation resulted in the defective splicing of ribosomal protein L2(rpl2)and ribosomal protein S12(rps12),which are involved in the synthesis of chloroplast 50S and 30S ribosomal subunits,respectively.The RNA-electrophoretic mobility shift assay(REMSA)further demonstrated that AL5 directly binds to rpl2 transcripts.Finally,disruption of AL5 led to reduced expression of plastid-encoded polymerase(PEP)-dependent plastid genes and nuclear-encoded photosynthetic genes.Notably,the albino al5 mutant phenotype was regulated by low temperature.These results suggest that AL5 participates in plastid RNA splicing and plays an important role in chloroplast development in rice.
基金the financial support from National Natural Science Foundation of China(Nos.82104082,81973247 and 82030107)Shanghai Municipal Commission of Science and Technology(Nos.19XD1400300 and 21430760800).
文摘Peptide and protein drugs with therapeutic effects suffer from their short half-life and low stability,albeit their high efficiency and specificity.To overcome these demerits,long-acting drug delivery systems have been developed,wherein poly(lactic-co-glycolic acid)(PLGA)implants are most preferred owing to their excellent biodegradability and biocompatibility.Dozens of PLGA based products have been approved since1986,when the first product,named Decapeptyl R,successfully marched into market.To meet the increasing demand for delivering various peptides and proteins,different kinds of technologies have been developed for lab-scale fabrication or industrial manufacture.This review aims to introduce recent advances of PLGA implants,and give a brief summary of fundamental properties of PLGA,fabrication technologies of peptides/proteins-loaded PLGA implants as well as factors influencing the drug release processes.Moreover,challenges and future perspectives are also highlighted.
基金supported by the National Natural Science Foundation of China(31572416,31372319,31330075 and 31110103909)Hubei Provincial Key Project for Scientific and Technical Innovation(2014ABA022)+2 种基金Hubei Hundred Talent program,Natural Science Foundation of Hubei Province(2013CFA097)Agriculture and Food Research Initiative Competitive Grants(2014-67015-21770 and 2015-67015-23276)from the USDA National Institute of Food and AgricultureTexas A&M Agri Life Research(H-8200)
文摘Recent years have witnessed growing interest in the role of peptides in animal nutrition. Chemical, enzymatic, or microbial hydrolysis of proteins in animal by-products or plant-source feedstuffs before feeding is an attractive means of generating high-quality small or large peptides that have both nutritional and physiological or regulatory functions in livestock, poultry and fish. These peptides may also be formed from ingested proteins in the gastrointestinal tract, but the types of resultant peptides can vary greatly with the physiological conditions of the animals and the composition of the diets. In the small intestine, large peptides are hydrolyzed to small peptides,which are absorbed into enterocytes faster than free amino acids（AAs） to provide a more balanced pattern of AAs in the blood circulation. Some peptides of plant or animal sources also have antimicrobial, antioxidant,antihypertensive, and immunomodulatory activities. Those peptides which confer biological functions beyond their nutritional value are called bioactive peptides. They are usually 2–20 AA residues in length but may consist of 〉20AA residues. Inclusion of some（e.g. 2–8%） animal-protein hydrolysates（e.g., porcine intestine, porcine mucosa,salmon viscera, or poultry tissue hydrolysates） or soybean protein hydrolysates in practical corn-and soybean mealbased diets can ensure desirable rates of growth performance and feed efficiency in weanling pigs, young calves,post-hatching poultry, and fish. Thus, protein hydrolysates hold promise in optimizing the nutrition of domestic and companion animals, as well as their health（particularly gut health） and well-being.
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.
文摘Peptide stapling strategy has been proven a promising solution in addressing two major pharmacological hurdles, proteolytic stability and membrane permeability, for small peptides as therapeutics. This stapling peptides feature a covalent cross-link of side chains, thus effectively mimicking α-helix as inhibitors of protein-protein interactions. In this review, we category and analyze key examples of various peptide stapling strategies based on different cross-links aligned on the side chain of peptides mainly in the last three years.
基金supported by National Key Research and Development Program of China(Grant No.2021YFE0115200)the Regional Innovation and Development Joint Fund of National Natural Science Foundation of China(Grant No.U22A20356).
文摘Solid lipid nanoparticles(SLN)could enhance the oral bioavailability of loaded protein and peptide drugs through lymphatic transport.Natural oligopeptides regulate nearly all vital processes and serve as a nitrogen source for nourishment.They are mainly transported by oligopeptide transporter-1(PepT-1)which are primarily expressed in the intestine with the characteristics of high-capacity and low energy consumption.Our preliminary research discovered the transmembrane transport of SLN could be improved by stimulating the oligopeptide absorption pathway.This implied the potential of combining the advantages of SLN with oligopeptide transporter mediated transportation.Herein,two kinds of dipeptide modified SLN were designed with insulin and glucagon like peptide-1(GLP-1)analogue exenatide as model drugs.These drugs loaded SLN showed enhanced oral bioavailability and hypoglycemic effect in both type I diabetic C57BL/6mice and type II diabetic KKAymice.Compared with un-modified SLN,dipeptide-modified SLN could be internalized by intestinal epithelial cells via PepT-1-mediated endocytosis with higher uptake.Interestingly,after internalization,more SLN could access the systemic circulation via lymphatic transport pathway,highlighting the potential to combine the oligopeptide-absorption route with SLN for oral drug delivery.
基金supported by grants from the Natural Science Foundation of China (No. 31301641 to J.Z.)the Program for Qualified Personnel of Taiwan Strait West Coast (No. K8812007 to L.H.X.)
文摘Banana bunchy top virus(BBTV)poses a serious danger to banana crops worldwide.BBTV-encoded protein B4 is a determinant of pathogenicity.However,the relevant molecular mechanisms underlying its effects remain unknown.In this study,we found that a functional peptide could be liberated from protein B4,likely via proteolytic processing.Site-directed mutagenesis indicated that the functional processing of protein B4 is required for its pathogenic effects,including dwarfism and sterility,in plants.The released protein fragment targets host proteins,such as the large subunit of RuBisCO(RbcL)and elongation factor 2(EF2),involved in protein synthesis.Therefore,the peptide released from B4(also a precursor)may act as a non-canonical modifier to influence host-pathogen interactions involving BBTV and plants.
基金supported by the National Key Research and Development Program of China (2021YFD2100402)the National Natural Science Foundation of China (81903275)the Fund of the Cultivation Project of Double First-Class Disciplines of Food Science and Engineering,Beijing Technology&Business University (BTBUYXTD202203)。
文摘Globally,the prevalence of anxiety and depression has reached epidemic proportions.Food-derived protein hydrolysates and peptides delivered through dietary supplementation can avoid the negative risks associated with traditional pharmaceuticals while delivering superior anxiolytic and antidepressant effects.This review summarizes current research on food-derived anxiolytic and antidepressant protein hydrolysates and peptides,and subsequently analyses their physicochemical characteristics and elaborates on their mechanisms.The aim of this work is to contribute to the in-depth study and provide a theoretical foundation for the development of related products to better serve patients with anxiety and depression.
基金supported by grants from the National Natural Science Foundation of China (31271800 and 31571742)the Zhejiang Provincial Natural Science Foundation of China (Z3110509)+1 种基金the National High-tech R&D Program of China (863 Program) (2012AA10A302-6)the Transgenic Project (2014ZX08010-002)
文摘Functional chloroplast generation depends on the precise coordination of gene expression between the plastid and the nucleus and is essential for plant growth and development. In this study, a rice（Oryza sativa） mutant that exhibited albino and seedling-lethal phenotypes was isolated from a60Co-irradiated rice population. The mutant gene was identified as an ortholog of the Arabidopsis plastid transcriptionally active chromosome protein 2（p TAC2） gene, and the mutant strain was designated osptac2. Sequence and transcription analyses showed that Osp TAC2 encodes a putative chloroplast protein consisting of 10 pentratricopeptide repeat（PPR） domains and a C-terminal small Mut S-related（SMR） domain. Cytological observations via microscopy showed that the Osp TAC2-green fluorescent fusion protein is localized in the chloroplasts. Transmission electron microscopy revealed that the chloroplast of the osptac2 mutant lacks an organized thylakoid membrane. The transcript levels of all investigated PEP（plastid-encoded RNA polymerase）-dependent genes were dramatically reduced in the osptac2 mutant, whereas the transcript levels of NEP（nuclear-encoded polymerase）-dependent genes were increased. These results suggest that Osp TAC2 plays a critical role in chloroplast development and indicate that the molecular function of the Osp TAC2 gene is conserved in rice and Arabidopsis.
基金This study was supported by grants from the National Natural Science Foun-dation of China( No:30472251 )and the Shanxi Youth Science Fund ( No.020011028).
文摘BACKGROUND: The development of a harmless and effi- cient nonviral gene delivery system that can facilitate the penetration of nucleic acids through the plasma membrane is a key to successful gene therapy. The aim of this study was to test a nonviral gene transferring vector's function of delivering DNA into liver cells to provide an important clue for gene transfer in liver gene therapy. METHODS: The complex of DNA and DNA delivering protein was injected into mice through their tail veins. Then the mice were killed and their liver tissue was sec- tioned. The gene transferring results were detected using a confocal laser scanning microscope. RESULTS: Fluorescence analysis indicated that both DNA- membrane penetrating peptide (MPP) complex and DNA- hepatocyte specific receptor binding domain ( HSRBD) - MPP complex could go into liver cells. The fluorescence value of liver cells in the DNA-HSRBD-MPP group was higher than that in the DNA-MPP group. CONCLUSIONS; MPP can successfully deliver DNA and protein into cells, and MPP with a HSRBD can specifically deliver DNA into liver cells. These have laid a foundation for further study on the nonviral liver cell gene delivering system.
基金supported by a grant from the National Natural Science Foundation of China(30260032.81000073 and 81160020)Key Program of Science and Technology of Hainan Province(061011 and ZDXM20100045)+2 种基金Education Department of Hainan Province(Hj2007113)Natural Science Foundation of Hainan Province(310043 and 811197)Key Project of Chinese Ministry of Education(212137) and HJHZ2013-06
文摘Objective:To understand the role of ANP mRNA transcription regulation in gpl30-mediated cardiomyocyte hypertrophy,and the involved mitogen-aetivated protein kinase kinase(MEK)-extracellular signal-regulated kinase(ERK,also called p42/p44 MAPK)signaling pathway.Methods:isolated neonatal ventricular myocytes were treated with different concentrations of CT-1(10^(-9),10^(-8)and 10^(-7)mol/L).MTT was used to analyze the viability and RT-PCR was used to detect ANP mRNA levels in eardiomyocyte.To inhibit p42/p44 MAPK activity in hypertrophic cardiomyoeytes,the cells were pretreated with a specific MEKI inhibitor.Results:CT-1significantly induced ANP mRNA expression and the viability of canliomyocytes in a doseand time-dependent manner.Furthermore,blocking p42/p44 MAPK activity by the special MEk1 inhibitor uprcgulatcd the ANP mKNA.Conclusions:p42/p44 MAPK have an important role in suppressing ANP mRNA transcription and cell activity in gpl30-mediated hypertrophic ventricular myocytes.
基金Supported by the National Natural Science Foundation of China,No.3973440-Ⅱ
文摘AIM:To purify the heat shock protein (HSP) 70-associated tumor peptides and to observe its non-MHC-I molecule restrictive antitumor effect.METHODS:By ConA-sepharose affinity chromatography,ADP-agarose affinity chromatography, and DEAE anion exchange chromatography, we were able to purify HSP70-associated peptides from mouse hepatoma (HCaF) cells treated in heat shock at 42℃. Specific active immunization and adoptive cellular immunization assay were adopted to observe the immunoprotective effect elicited by HSP70-associated peptide complexes isolated from HcaF.RESULTS: The finally purified HSP-associated peptides had a very high purity and specificity found by SDS-PAGE and Western blot. Mice immunized with HSP70-associated peptide complexes purified from HCaF cells were protected from HCaF living cell challenge. This effect was dose dependent.Adoptive immunization of immune spleen cells of mice immunized with HSP70-associated peptide complexes could elicit immunity against HCaF challenge, and the tumor-free mice could resist repeated challenges. This effect could be continuously enhanced by repeated challenge with HCaF living cells. The tumor-free mice could tolerate the challenge for as high as 1×10^7 HCaF cells. The mice immunized once with spleen cells pulsed with HSP70-associated peptide complexes in vitro could also result in a certain adoptive immunity against HCaF.CONCLUSION:High purity and specificity of HSP70-associated peptides could be achieved from tumor cells by the low-pressure affinity chromatography method used in this study. HSP70-associated peptide complexes derived from the HCaF can elicit non-MHC-I molecule restrictive immunoprotective effect against HCaF.This effect can be transferred by adoptive immunization to mice and enhanced by repeated challenge with HCaF live cells.
