To compare liver proteolysis and proteasome activation in steatotic liver grafts conserved in University of Wisconsin(UW)and Institut Georges Lopez-1(IGL-1)solutions.METHODSFatty liver grafts from male obese Zück...To compare liver proteolysis and proteasome activation in steatotic liver grafts conserved in University of Wisconsin(UW)and Institut Georges Lopez-1(IGL-1)solutions.METHODSFatty liver grafts from male obese Zücker rats were conserved in UW and IGL-1 solutions for 24 h at 4°Cand subjected to“ex vivo”normo-thermic perfusion(2 h;37°C).Liver proteolysis in tissue specimens and perfusate was measured by reverse-phase high performance liquid chromatography.Total free amino acid release was correlated with the activation of the ubiquitin proteasome system(UPS:measured as chymotryptic-like activity and 20S and 19S proteasome),the prevention of liver injury(transaminases),mitochondrial injury(confocal microscopy)and inflammation markers(TNF 1 alpha,high mobility group box-1(HGMB-1)and PPAR gamma),and liver apoptosis(TUNEL assay,cytochrome c and caspase 3).RESULTSProfiles of free AA(alanine,proline,leucine,isoleucine,methionine,lysine,ornithine,and threonine,among others)were similar for tissue and reperfusion effluent.In all cases,the IGL-1 solution showed a significantly higher prevention of proteolysis than UW(P<0.05)after cold ischemia reperfusion.Livers conserved in IGL-1 presented more effective prevention of ATP-breakdown and more inhibition of UPS activity(measured as chymotryptic-like activity).In addition,the prevention of liver proteolysis and UPS activation correlated with the prevention of liver injury(AST/ALT)and mitochondrial damage(revealed by confocal microscopy findings)as well as with the prevention of inflammatory markers(TNF1alpha and HMGB)after reperfusion.In addition,the liver grafts preserved in IGL-1 showed a significant decrease in liver apoptosis,as shown by TUNEL assay and the reduction of cytochrome c,caspase 3 and P62 levels.CONCLUSIONOur comparison of these two preservation solutions suggests that IGL-1 helps to prevent ATP breakdown more effectively than UW and subsequently achieves a higher UPS inhibition and reduced liver proteolysis.展开更多
Neurological diseases such as stroke,Alzheimer’s disease,Parkinson’s disease,and Huntington’s disease are among the intractable diseases for which appropriate drugs and treatments are lacking.Proteolysis targeting ...Neurological diseases such as stroke,Alzheimer’s disease,Parkinson’s disease,and Huntington’s disease are among the intractable diseases for which appropriate drugs and treatments are lacking.Proteolysis targeting chimera(PROTAC)technology is a novel strategy to solve this problem.PROTAC technology uses the ubiquitin-protease system to eliminate mutated,denatured,and harmful proteins in cells.It can be reused,and utilizes the protein destruction mechanism of the cells,thus making up for the deficiencies of traditional protein degradation methods.It can effectively target and degrade proteins,including proteins that are difficult to identify and bind.Therefore,it has extremely important implications for drug development and the treatment of neurological diseases.At present,the targeted degradation of mutant BTK,mHTT,Tau,EGFR,and other proteins using PROTAC technology is gaining attention.It is expected that corresponding treatment of nervous system diseases can be achieved.This review first focuses on the recent developments in PROTAC technology in terms of protein degradation,drug production,and treatment of central nervous system diseases,and then discusses its limitations.This review will provide a brief overview of the recent application of PROTAC technology in the treatment of central nervous system diseases.展开更多
The ASK1 （ARABIDOPSIS SKP1-LIKE） protein is a critical component of the SCF （Skpl-Cullin-F box protein） ubiquitin ligase complexes that recruit target proteins for degradation by the 26S proteosome. To investigate...The ASK1 （ARABIDOPSIS SKP1-LIKE） protein is a critical component of the SCF （Skpl-Cullin-F box protein） ubiquitin ligase complexes that recruit target proteins for degradation by the 26S proteosome. To investigate proteins that are affected by the ASK1-mediated proteolysis pathway in Arabidopsis flowers, we compared the proteomes of the Arabidopsis wild type and ask1 mutant flower buds using two-dimensional electrophoresis （2-DE）. Ten protein spots with higher or lower abundance in the ask1 mutant flowers compared to wild type flowers were excised and subjected to further mass spectrometry （MS） analysis. The results showed that they were proteins involved in photomorphogenesis, circadian oscillation, post-translation process, stress-responses and cell expansion or elongation, suggesting that those processes were affected in the ask1 mutant. The transcript levels of these genes were also compared based on the Affymetrix gene chip microarray data. No significant difference was observed for most of the genes, suggesting that the proteins with elevated levels of accumulation in the ask1 mutant could be candidate targets regulated by an ASK 1-mediated proteolysis pathway. These results help to elucidate the pleiotropic functions of ASK1 in Arabidopsis developmental processes and also demonstrate the importance and necessity of studying protein levels with respect to gene functions.展开更多
The amino acid biosynthesis and proteolytic system of Lactobacillus bulgaricus (L.Bulgaricus ) is important for its growth in niche-specific environments, as well as for flavour formation in the food industry. Compara...The amino acid biosynthesis and proteolytic system of Lactobacillus bulgaricus (L.Bulgaricus ) is important for its growth in niche-specific environments, as well as for flavour formation in the food industry. Comparative analyses of 4 completed sequences of the L.Bulgaricus strain genome on a genomic scale revealed that genes involved in amino acids synthesis were undergoing reductive evolution. However, the selected industrial strains, namely, L.Bulgaricus 2038 and L.Bulgaricus ND02, retained more complete genes in the amino acid synthesis and proteolytic system category than the laboratory strains, and have some unique genes and pathways for obtaining amino acids that enable these bacteria to adapt to their various environmental niches.展开更多
We screened 95 kinase inhibitors whether they affect cAMP-dependent proteolysis of GATA-6 or not. Among them 7 inhibitors inhibited the proteolysis at the concentration range of μM around their IC50. They are inhibit...We screened 95 kinase inhibitors whether they affect cAMP-dependent proteolysis of GATA-6 or not. Among them 7 inhibitors inhibited the proteolysis at the concentration range of μM around their IC50. They are inhibitors for protein kinase A (H-89 and 4- cyano-3-methylisoquinoline), c-Jun N-terminal kinase (SP600125), phosphatidylinositol 3-kinase (Wort- mannin and LY-294002), casein kinase II (TBB) and cyclin dependent kinase (Cdk1/2 inhibitor III). It is of interest how these kinases play roles in the degradation process of GATA-6 since this transcription factor is essential for development and tissue-specific gene expression of mammals. Inhibitors identified in this study would be helpful to study molecular mechanisms of phenomena in which GATA-6 participates.展开更多
Dimethyl curcumin,a synthetic derivative of curcumin,has good anti-cancer,anti-arthritis and anti-inflammatory properties,but underline mechanism was unclear.Activation,differentiation,proliferation and apoptosis of l...Dimethyl curcumin,a synthetic derivative of curcumin,has good anti-cancer,anti-arthritis and anti-inflammatory properties,but underline mechanism was unclear.Activation,differentiation,proliferation and apoptosis of lymphocytes have important functions during arthritis development and immune homeostasis.Over-activation of lymphocyte causes inflammatory cytokines storm,leading to an immune imbalance and tissue damages.The aim of this study was to investigate the anti-inflammation mechanism of liposome encapsulated dimethyl curcumin(Lipo-DiMC)on over-activated rat spleen lymphocytes.In this study,Lipo-DiMC was produced to increase the solubility;the primary rat spleen lymphocytes were extracted and the Concanavalin A induced cell activation model was established to study the cellular responses to Lipo-DiMC treatment in-vitro.The results showed that Lipo-DiMC suppressed Concanavalin A-induced cell proliferation,inhibited cells entering G2/M phase,and reduced the ratio of necrosis/apoptosis by manipulating intracellular p53/p21/PCNA/JNK-1 pathways.Furthermore,Lipo-DiMC increased the accumulations of intracellular matrix metalloproteinase-9 and reduced matrix metalloproteinase-9 secretion of rat spleen lymphocytes.Also,Lipo-DiMC increased intracellular caspase-3 expression and reduced Cat-C activity in activated rat spleen lymphocytes,involving in intracellular proteolysis.Our findings suggest that dimethyl curcumin effectively alleviates Concanavalin A induced over-activation of rat spleen lymphocytes,thereby inhibiting inflammatory cytokines storm and restoring cell homeostasis.展开更多
Dipeptidyl peptidase-IV(DPP-4)enzyme inhibitors are a promising category of diabetes medications.Bioactive peptides,particularly those derived from bovine milk proteins,play crucial roles in inhibiting the DPP-4 enzym...Dipeptidyl peptidase-IV(DPP-4)enzyme inhibitors are a promising category of diabetes medications.Bioactive peptides,particularly those derived from bovine milk proteins,play crucial roles in inhibiting the DPP-4 enzyme.This study describes a comprehensive strategy for DPP-4 inhibitory peptide discovery and validation that combines machine learning and virtual proteolysis techniques.Five machine learning models,including GBDT,XGBoost,LightGBM,CatBoost,and RF,were trained.Notably,LightGBM demonstrated superior performance with an AUC value of 0.92±0.01.Subsequently,LightGBM was employed to forecast the DPP-4 inhibitory potential of peptides generated through virtual proteolysis of milk proteins.Through a series of in silico screening process and in vitro experiments,GPVRGPF and HPHPHL were found to exhibit good DPP-4 inhibitory activity.Molecular docking and molecular dynamics simulations further confirmed the inhibitory mechanisms of these peptides.Through retracing the virtual proteolysis steps,it was found that GPVRGPF can be obtained fromβ-casein through enzymatic hydrolysis by chymotrypsin,while HPHPHL can be obtained fromκ-casein through enzymatic hydrolysis by stem bromelain or papain.In summary,the integration of machine learning and virtual proteolysis techniques can aid in the preliminary determination of key hydrolysis parameters and facilitate the efficient screening of bioactive peptides.展开更多
γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the ...γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general.展开更多
Post-translational modifications play essential roles in finely modulating eukaryotic circadian clock systems.In plants,the effects of O-glycosylation on the circadian clock and the underlying mechanisms remain largel...Post-translational modifications play essential roles in finely modulating eukaryotic circadian clock systems.In plants,the effects of O-glycosylation on the circadian clock and the underlying mechanisms remain largely unknown.The O-fucosyltransferase SPINDLY(SPY)and the O-GIcNAc transferase SECRET AGENT(SEC)are two prominent O-glycosylation enzymes in higher plants,with both overlapped and unique functions in plant growth and development.Unlike the critical role of O-GIcNAc in regulating the animal circadian clock,here we report that nuclear-localized SPY,but not SEC,specifically modulates the pace of the Arabidopsis circadian clock.By identifying the interactome of SPY,we identified PSEUDORESPONSE REGULATOR 5(PRR5),one of the core circadian clock components,as a new SPY-interacting protein.PRR5 can be O-fucosylated by SPY in pianta,while point mutation in the catalytic domain of SPY abolishes the O-fucosylation of PRR5.The protein abundance of PRR5 is strongly increased in spy mutants,while the degradation rate of PRR5 is much reduced,suggesting that PRR5 proteolysis is promoted by SPY-mediated O-fucosylation.Moreover,multiple lines of genetic evidence indicate that PRR5 is a major downstream target of SPY to specifically mediate its modulation of the circadian clock.Collectively,our findings provide novel insights into the specific role of the O-fucosyltransferase activity of SPY in modulating the circadian clock and implicate that O-glycosylation might play an evolutionarily conserved role in modulating the circadian clock system,via O-GIcNAcylation in mammals,but via O-fuco-sylation in higher plants.展开更多
This review gives a broad glance on the progress of recent advances on proteolysis and peptide/protein separation by chroma-tographic strategies in the past ten years, covering the main research in these areas especia...This review gives a broad glance on the progress of recent advances on proteolysis and peptide/protein separation by chroma-tographic strategies in the past ten years, covering the main research in these areas especially in China. The reviewed research focused on enzymatic micro-reactors and peptide separation in bottom-up approaches, and protein and peptide separation in top-down approaches. The new enzymatic micro-reactor is able to accelerate proteolytic reaction rate from conventionally a couple of hours to a few seconds, and the multiple dimensional chromatographic-separation with various models or arrays could sufficiently separate the proteomic mixture. These advances have significantly promoted the research of protein/peptide separation and identification in proteomics.展开更多
The occurrence of twin-arginine motifs （-R-R-） in the amino acid sequences of animal pro-proteins frequently defines the cleavage site（s） for their structural/functional maturation. No information is available on ...The occurrence of twin-arginine motifs （-R-R-） in the amino acid sequences of animal pro-proteins frequently defines the cleavage site（s） for their structural/functional maturation. No information is available on the presence and possible biological meaning of these motifs in the seed storage proteins. In this work, a novel endopeptidase activity with cleavage specificity to twin-arginine pairs has been detected in mature dry Lupinus albus seeds. The endopeptidase was tested with a number of endogenous and exogenous protein substrates, which were selected according to the pres- ence of one or more twin-arginine residue motifs in their amino acid sequences. The observed hydrolysis patterns were limited and highly specific. Partial proteolysis led to stable polypeptide fragments that were characterized by 1- and 2-D electrophoresis. Selected polypeptides were submitted to N-terminal amino acid sequencing and mass spectrometry anal- yses, These approaches, supported by bioinformatic analysis of the available sequences, allowed the conclusion that the polypeptide cleavage events had occurred at the peptide bonds comprised between twin-arginine residue pairs with all tested protein substrates. The endopeptidase activity was inhibited by 4-（2-AminoEthyl）Benzene-Sulphonyl Fluoride hy- drochloride （AEBSF）, leupeptin, and serine proteinase protein inhibitors, while it was not affected by pepstatin, trans- EpoxysuccinyI-L-leucylamido（4-guanidino）butane （E64）, and ethylenediaminetetraacetic acid （EDTA）, thus qualifying the Arg-Arg cleaving enzyme as a serine endopeptidase. The structural features of storage proteins from lupin and other legume seeds strongly support the hypothesis that the occurrence of an endopeptidase activity cleaving -R-R- bonds may be functional to facilitate their degradation at germination and possibly generate polypeptide fragments with specific biological activity.展开更多
Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify...Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify the proteolytic products of proteins, but also be used to research the dynamics of proteolytic reactions. The proteolysis of melittin by trypsin gave seven main peptide fragments: 1, AA 1 AA 7 ; 2, AA 1 AA 21 ;3, AA 1 AA 22 ; 4, AA 1 AA 23 ; 5, AA 1 AA 24 ; 6, AA 8 AA 21 ; 7, AA 8 AA 22 . The proteolysis of melittin with pepsin gave thirteen peptide fragments: 1, AA 1 AA 3; 2, AA 4 AA 6;3, AA 1 AA 4;4, AA 1 AA 5 ;5, AA 1 AA 6 ;6, AA 1 AA 8;7, AA 7 AA 13 ;8, AA 10 AA 13 ;9, AA 14 AA 16 ;10, AA 14 AA 26 ;11, AA 15 AA 26 ;12, AA 17 AA 26 ;13, AA 20 AA 26 .展开更多
Over the past 20 years,great efforts have been invested in developing site-specific approaches to protein modification to dissect protein functions directly and accurately.Here,we report a proximitytriggered group tra...Over the past 20 years,great efforts have been invested in developing site-specific approaches to protein modification to dissect protein functions directly and accurately.Here,we report a proximitytriggered group transfer strategy from a sulfonium warhead to a Cysteine(Cys)residue of the target protein.With a guiding ligand,cargoes could be transferred selectively from a sulfonium center onto the Cys residue in the vicinity of their binding interface.The successful thalidomide transfer of sulfonium 1-X could be applied intracellularly for epidermal growth factor receptor degradation,highlighting the potential of group transfer strategy as a suite of chemical biology studies,including cell imaging,protein profiling,and protein degradation by simply employing different transferrable groups.展开更多
Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.T...Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.The purpose aimed to reveal the potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa in this paper.The dynamic changes of endogenous proteases activity,free amino acids,and volatiles during dry-cured pork coppa processing were characterized.The results showed that 5 kinds of free amino acids,Glu,Lys,Val,Ala,and Leu,were identified as significant contributors to taste.Meanwhile,key volatiles,such as hexanal,nonanal,octanal,benzaldehyde,3-methyl butanoic acid,2-methyl propanoic acid,and ethyl octanoate,greatly contributed to the flavor characteristics of dry-cured pork coppa.Further partial correlation analysis was performed to better elucidate the relationship among parameters.The results revealed that close relationship between endogenous proteases and key substances.RAP not only significantly affected the accumulation of key active-amino acids,but also affected the accumulation of ethyl octanoate,2,3-pentanedione,and 2,3-octanedione by regulating the accumulation of octanoic acid and Leu.In addition,cathepsin B and D,DPP II,DPP IV and RAP notably affected accumulation of hexanal.展开更多
Leucine-richα-2 glycoprotein 1(LRG1),a secreted glycoprotein,has been identified as significantly upregulated in renal fibrosis,potentially exacerbating the condition by enhancing TGF-β-Smad3-dependent signaling pat...Leucine-richα-2 glycoprotein 1(LRG1),a secreted glycoprotein,has been identified as significantly upregulated in renal fibrosis,potentially exacerbating the condition by enhancing TGF-β-Smad3-dependent signaling pathways.Herein,utilizing our developed LRG1-targeting peptide for LRG1 recruitment and lenalidomide for E3 ubiquitin ligase engagement,we developed an advanced proteolysis targeting chimera,^(ET)TAC-2,specifically designed for LRG1 degradation.Our cellular degradation assays validated that ^(ET)TAC-2 effectively degraded LRG1 through a proteasome-dependent mechanism,achieving halfmaximal degradation at a concentration of 8.38μM.Furthermore,anti-fibrotic experiments conducted both in vitro and in vivo revealed that ^(ET)TAC-2 efficiently induced LRG1 degradation in fibrotic kidneys.This action effectively inhibited the TGF-β-Smad3 signaling pathway and diminished the secretion of fibrosis-associated proteins,consequently attenuating the progression of renal fibrosis.Our study highlights the pivotal role of LRG1 in renal fibrosis and positions ^(ET)TAC-2 as a promising therapeutic candidate for targeted LRG1 intervention.展开更多
The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual scree...The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual screening,compound synthesis,in vitro bioassay and proteolysis.Six subtypes of hemp seed edestin and albumin were in silico hydrolyzed by 29 proteases,and 192 encrypted bioactive peptides were screened out.Six peptides showed to be XOI peptides,of which four(about 67%)were released by elastase hydrolysis.The peptide DDNPRRFY displayed the highest XOI activity(IC50=(2.10±0.06)mg/mL),acting as a mixed inhibitor.The pancreatic elastase directionally prepared XOI hemp seed protein hydrolysates,from which 6 high-abundance XOI peptides encrypted 3 virtually-screened ones including the DDNPRRFY.The novel outstanding hemp seed protein-derived XOI peptides and their virtual screening and directed preparation methods provide a promising and applicable approach to conveniently and efficiently explore food-derived bioactive peptides.展开更多
Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransfor...Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransformation of nutrients occurs,resulting in notable changes to proteins,carbohydrates,fats,vitamins,and minerals.Each nutrient undergoes specific transformations,providing various advantages for human health.Proteins undergo hydrolysis to produce small molecular weight peptides and amino acids that are more easily digested and absorbed by the human body.Carbohydrates break down to improve the digestibility and absorption of cereals and lower the glycemic index.Fatty acids experience oxidation to produce new substances with health benefits.Additionally,the application of sourdough fermentation can enhance the texture,flavor,and nutritional value of cereal foods while also extending their shelf life and improving food safety.In conclusion,sourdough fermentation has a broad range of applications in cereal food processing.Further research is encouraged to investigate the mechanisms and processes of sourdough fermentation to develop even more nutritious,healthy,and flavorful cereal-based foods.展开更多
Objectives Exercise training induces several skeletal muscle adaptations.Beta-guanidinopropionic acid(β-GPA)is a creatine analog that simulates the effect of exercise to induce mitochondrial biogenesis.However,the ef...Objectives Exercise training induces several skeletal muscle adaptations.Beta-guanidinopropionic acid(β-GPA)is a creatine analog that simulates the effect of exercise to induce mitochondrial biogenesis.However,the effects ofβ-GPA on resistance training adaptation,such as muscle hypertrophy and mitochondrial biogenesis,are unclear.Therefore,using a resistance exercise model in rats,the present study was designed to investigate the effects ofβ-GPA administration on resistance training adaptations.Methods This study was approved by the Ethics Committee for Animal Experiments at Ritsumeikan University(approval number:BKC2022-009).Male Sprague Dawley rats were randomly divided into placebo orβ-GPA groups.β-GPA(1000 mg/kg)was orally administered once daily,starting seven days before the initiation of electromyostimulation as a model for resistance exercise,and continued throughout the training period.Electromyostimulation was applied to the right gastrocnemius muscle via electrical stimulation every other day for a total of 12 sessions Results Peroxisome proliferators-activated receptor-γco-activator-1α,a regulator of mitochondrial biogenesis,was significantly increased by the combination of training andβ-GPA compared to the training leg(p<0.05).Protein expression of Total OXPHOS,a marker of mitochondrial content,was significantly increased by the combination of training andβ-GPA compared to the training leg(p<0.05).β-GPA intake reduced muscle mass(main effect ofβ-GPA,p<0.05)and was associated with muscle protein breakdown-related Fbx32 and LC3-II protein expression levels but did not counteract the increase in muscle mass caused by resistance training.Conclusions Administration of exogenousβ-GPA enhanced resistance training-induced mitochondrial biogenesis.Moreover,β-GPA still permitted resistance electromyostimulation-induced muscle mass gains,but that effect was attenuated as compared to placebo.展开更多
F-box protein is an expanding family member of eukaryotic protein characterized by an F-box motif which has specificity of substrate recognition in the ubiquitin-mediated proteolysis.These proteins have been proved to...F-box protein is an expanding family member of eukaryotic protein characterized by an F-box motif which has specificity of substrate recognition in the ubiquitin-mediated proteolysis.These proteins have been proved to be critical for many physiological processes,such as cell-cycle transition,signal transduction,gene transcription,male sterility,programmed cell death （PCD） and so on.This paper mainly introduces the biological functions of the known F-box proteins and the analysis of F-box gene phylogeny.展开更多
Macroautophagy is a multistep, vacuolar, degradation pathway terminating in the lysosomal compartment, and it is of fundamental importance in tissue homeostasis. In this review, we consider macroautophagy in the light...Macroautophagy is a multistep, vacuolar, degradation pathway terminating in the lysosomal compartment, and it is of fundamental importance in tissue homeostasis. In this review, we consider macroautophagy in the light of recent advances in our understanding of the formation of autophagosomes, which are double-membrane-bound vacuoles that sequester cytoplasmic cargos and deliver them to lysosomes. In most cases, this final step is preceded by a maturation step during which autophagosomes interact with the endocytic pathway. The discovery of AuTophaGyrelated genes has greatly increased our knowledge about the mechanism responsible for antophagosome formation, and there has also been progress in the understanding of molecular aspects of autophagosome maturation. Finally, the regulation of autophagy is now better understood because of the discovery that the activity of Atg complexes is targeted by protein kinases, and owing to the importance of nuclear regulation via transcription factors in regulating the expression of autophagy genes.展开更多
基金Supported by Instituto de Salud Carlos III(ISCIII)through the FIS project PI12/0056,co-funded by FEDER from Regional Development European Funds(European Union)
文摘To compare liver proteolysis and proteasome activation in steatotic liver grafts conserved in University of Wisconsin(UW)and Institut Georges Lopez-1(IGL-1)solutions.METHODSFatty liver grafts from male obese Zücker rats were conserved in UW and IGL-1 solutions for 24 h at 4°Cand subjected to“ex vivo”normo-thermic perfusion(2 h;37°C).Liver proteolysis in tissue specimens and perfusate was measured by reverse-phase high performance liquid chromatography.Total free amino acid release was correlated with the activation of the ubiquitin proteasome system(UPS:measured as chymotryptic-like activity and 20S and 19S proteasome),the prevention of liver injury(transaminases),mitochondrial injury(confocal microscopy)and inflammation markers(TNF 1 alpha,high mobility group box-1(HGMB-1)and PPAR gamma),and liver apoptosis(TUNEL assay,cytochrome c and caspase 3).RESULTSProfiles of free AA(alanine,proline,leucine,isoleucine,methionine,lysine,ornithine,and threonine,among others)were similar for tissue and reperfusion effluent.In all cases,the IGL-1 solution showed a significantly higher prevention of proteolysis than UW(P<0.05)after cold ischemia reperfusion.Livers conserved in IGL-1 presented more effective prevention of ATP-breakdown and more inhibition of UPS activity(measured as chymotryptic-like activity).In addition,the prevention of liver proteolysis and UPS activation correlated with the prevention of liver injury(AST/ALT)and mitochondrial damage(revealed by confocal microscopy findings)as well as with the prevention of inflammatory markers(TNF1alpha and HMGB)after reperfusion.In addition,the liver grafts preserved in IGL-1 showed a significant decrease in liver apoptosis,as shown by TUNEL assay and the reduction of cytochrome c,caspase 3 and P62 levels.CONCLUSIONOur comparison of these two preservation solutions suggests that IGL-1 helps to prevent ATP breakdown more effectively than UW and subsequently achieves a higher UPS inhibition and reduced liver proteolysis.
基金This work was supported by the National Natural Science Foundation of China,No.81870975(to SLZ)the Nantong Science and Technology Innovation Program,China,No.JC2019028(to XMY).
文摘Neurological diseases such as stroke,Alzheimer’s disease,Parkinson’s disease,and Huntington’s disease are among the intractable diseases for which appropriate drugs and treatments are lacking.Proteolysis targeting chimera(PROTAC)technology is a novel strategy to solve this problem.PROTAC technology uses the ubiquitin-protease system to eliminate mutated,denatured,and harmful proteins in cells.It can be reused,and utilizes the protein destruction mechanism of the cells,thus making up for the deficiencies of traditional protein degradation methods.It can effectively target and degrade proteins,including proteins that are difficult to identify and bind.Therefore,it has extremely important implications for drug development and the treatment of neurological diseases.At present,the targeted degradation of mutant BTK,mHTT,Tau,EGFR,and other proteins using PROTAC technology is gaining attention.It is expected that corresponding treatment of nervous system diseases can be achieved.This review first focuses on the recent developments in PROTAC technology in terms of protein degradation,drug production,and treatment of central nervous system diseases,and then discusses its limitations.This review will provide a brief overview of the recent application of PROTAC technology in the treatment of central nervous system diseases.
基金We thank Dr Yue Jun from Institute of Genetics at Fudan University for kind help and advice on 2-DE technique,Hasan Koc from the proteomic center at the Pennsylvania State University for help with protein identification with MS and Qing Zhang for assistance with the normalization of the microarray data.This work was supported by the Youth Exploration Funding of School of Life Sciences at Fudan Universityin part by a grant to H.M.from the US National Science Foundation(MCB-0092075).
文摘The ASK1 （ARABIDOPSIS SKP1-LIKE） protein is a critical component of the SCF （Skpl-Cullin-F box protein） ubiquitin ligase complexes that recruit target proteins for degradation by the 26S proteosome. To investigate proteins that are affected by the ASK1-mediated proteolysis pathway in Arabidopsis flowers, we compared the proteomes of the Arabidopsis wild type and ask1 mutant flower buds using two-dimensional electrophoresis （2-DE）. Ten protein spots with higher or lower abundance in the ask1 mutant flowers compared to wild type flowers were excised and subjected to further mass spectrometry （MS） analysis. The results showed that they were proteins involved in photomorphogenesis, circadian oscillation, post-translation process, stress-responses and cell expansion or elongation, suggesting that those processes were affected in the ask1 mutant. The transcript levels of these genes were also compared based on the Affymetrix gene chip microarray data. No significant difference was observed for most of the genes, suggesting that the proteins with elevated levels of accumulation in the ask1 mutant could be candidate targets regulated by an ASK 1-mediated proteolysis pathway. These results help to elucidate the pleiotropic functions of ASK1 in Arabidopsis developmental processes and also demonstrate the importance and necessity of studying protein levels with respect to gene functions.
文摘The amino acid biosynthesis and proteolytic system of Lactobacillus bulgaricus (L.Bulgaricus ) is important for its growth in niche-specific environments, as well as for flavour formation in the food industry. Comparative analyses of 4 completed sequences of the L.Bulgaricus strain genome on a genomic scale revealed that genes involved in amino acids synthesis were undergoing reductive evolution. However, the selected industrial strains, namely, L.Bulgaricus 2038 and L.Bulgaricus ND02, retained more complete genes in the amino acid synthesis and proteolytic system category than the laboratory strains, and have some unique genes and pathways for obtaining amino acids that enable these bacteria to adapt to their various environmental niches.
文摘We screened 95 kinase inhibitors whether they affect cAMP-dependent proteolysis of GATA-6 or not. Among them 7 inhibitors inhibited the proteolysis at the concentration range of μM around their IC50. They are inhibitors for protein kinase A (H-89 and 4- cyano-3-methylisoquinoline), c-Jun N-terminal kinase (SP600125), phosphatidylinositol 3-kinase (Wort- mannin and LY-294002), casein kinase II (TBB) and cyclin dependent kinase (Cdk1/2 inhibitor III). It is of interest how these kinases play roles in the degradation process of GATA-6 since this transcription factor is essential for development and tissue-specific gene expression of mammals. Inhibitors identified in this study would be helpful to study molecular mechanisms of phenomena in which GATA-6 participates.
基金This work is supported by the Start-up Research Laboratory for Over-sea Talent Fund,China(No.Z391405)to ProfXiaoying Zhou and the Changzhou University Undergraduate Innovation and Entrepreneurship Fund,China(No.2019-02-C-96)to Ya-Ming Guo.
文摘Dimethyl curcumin,a synthetic derivative of curcumin,has good anti-cancer,anti-arthritis and anti-inflammatory properties,but underline mechanism was unclear.Activation,differentiation,proliferation and apoptosis of lymphocytes have important functions during arthritis development and immune homeostasis.Over-activation of lymphocyte causes inflammatory cytokines storm,leading to an immune imbalance and tissue damages.The aim of this study was to investigate the anti-inflammation mechanism of liposome encapsulated dimethyl curcumin(Lipo-DiMC)on over-activated rat spleen lymphocytes.In this study,Lipo-DiMC was produced to increase the solubility;the primary rat spleen lymphocytes were extracted and the Concanavalin A induced cell activation model was established to study the cellular responses to Lipo-DiMC treatment in-vitro.The results showed that Lipo-DiMC suppressed Concanavalin A-induced cell proliferation,inhibited cells entering G2/M phase,and reduced the ratio of necrosis/apoptosis by manipulating intracellular p53/p21/PCNA/JNK-1 pathways.Furthermore,Lipo-DiMC increased the accumulations of intracellular matrix metalloproteinase-9 and reduced matrix metalloproteinase-9 secretion of rat spleen lymphocytes.Also,Lipo-DiMC increased intracellular caspase-3 expression and reduced Cat-C activity in activated rat spleen lymphocytes,involving in intracellular proteolysis.Our findings suggest that dimethyl curcumin effectively alleviates Concanavalin A induced over-activation of rat spleen lymphocytes,thereby inhibiting inflammatory cytokines storm and restoring cell homeostasis.
基金supported by the National Key Research and Development Project(2018YFE0206300-02).
文摘Dipeptidyl peptidase-IV(DPP-4)enzyme inhibitors are a promising category of diabetes medications.Bioactive peptides,particularly those derived from bovine milk proteins,play crucial roles in inhibiting the DPP-4 enzyme.This study describes a comprehensive strategy for DPP-4 inhibitory peptide discovery and validation that combines machine learning and virtual proteolysis techniques.Five machine learning models,including GBDT,XGBoost,LightGBM,CatBoost,and RF,were trained.Notably,LightGBM demonstrated superior performance with an AUC value of 0.92±0.01.Subsequently,LightGBM was employed to forecast the DPP-4 inhibitory potential of peptides generated through virtual proteolysis of milk proteins.Through a series of in silico screening process and in vitro experiments,GPVRGPF and HPHPHL were found to exhibit good DPP-4 inhibitory activity.Molecular docking and molecular dynamics simulations further confirmed the inhibitory mechanisms of these peptides.Through retracing the virtual proteolysis steps,it was found that GPVRGPF can be obtained fromβ-casein through enzymatic hydrolysis by chymotrypsin,while HPHPHL can be obtained fromκ-casein through enzymatic hydrolysis by stem bromelain or papain.In summary,the integration of machine learning and virtual proteolysis techniques can aid in the preliminary determination of key hydrolysis parameters and facilitate the efficient screening of bioactive peptides.
基金supported in part by Award 2121063 from National Science Foundation(to YM)AG66986 from the National Institutes of Health(to MSW).
文摘γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface receptors.Mutations inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as well.However,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-secretase.In this review,we focus on recent studies of structural dynamic mechanisms ofγ-secretase.Different mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics simulations.While an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental findings.The approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-secretase.In addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is discussed.Finally,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations of theγ-secretase-substrate complexes.Comprehensive understanding of the functional mechanisms ofγ-secretase will greatly facilitate the rational design of effective drug molecules for treating familial Alzheimer’s disease and perhaps Alzheimer’s disease in general.
基金suppoded by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB27030206)National Natural Science Foundation of China(No.31770287)+1 种基金National Key Research and Development Program of China(2016YFD0100600)to L.W.the National Institutes of Health(R01 GM100051)to T.P.S.
文摘Post-translational modifications play essential roles in finely modulating eukaryotic circadian clock systems.In plants,the effects of O-glycosylation on the circadian clock and the underlying mechanisms remain largely unknown.The O-fucosyltransferase SPINDLY(SPY)and the O-GIcNAc transferase SECRET AGENT(SEC)are two prominent O-glycosylation enzymes in higher plants,with both overlapped and unique functions in plant growth and development.Unlike the critical role of O-GIcNAc in regulating the animal circadian clock,here we report that nuclear-localized SPY,but not SEC,specifically modulates the pace of the Arabidopsis circadian clock.By identifying the interactome of SPY,we identified PSEUDORESPONSE REGULATOR 5(PRR5),one of the core circadian clock components,as a new SPY-interacting protein.PRR5 can be O-fucosylated by SPY in pianta,while point mutation in the catalytic domain of SPY abolishes the O-fucosylation of PRR5.The protein abundance of PRR5 is strongly increased in spy mutants,while the degradation rate of PRR5 is much reduced,suggesting that PRR5 proteolysis is promoted by SPY-mediated O-fucosylation.Moreover,multiple lines of genetic evidence indicate that PRR5 is a major downstream target of SPY to specifically mediate its modulation of the circadian clock.Collectively,our findings provide novel insights into the specific role of the O-fucosyltransferase activity of SPY in modulating the circadian clock and implicate that O-glycosylation might play an evolutionarily conserved role in modulating the circadian clock system,via O-GIcNAcylation in mammals,but via O-fuco-sylation in higher plants.
基金support from the Major State Basie Research Development Program (Grant No. 2007CB914100)the National Natural Science Foundation of China (Grant Nos. 20875016 & 20735005)Shanghai Projects (Grant Nos. 08DZ2293601 & B109)
文摘This review gives a broad glance on the progress of recent advances on proteolysis and peptide/protein separation by chroma-tographic strategies in the past ten years, covering the main research in these areas especially in China. The reviewed research focused on enzymatic micro-reactors and peptide separation in bottom-up approaches, and protein and peptide separation in top-down approaches. The new enzymatic micro-reactor is able to accelerate proteolytic reaction rate from conventionally a couple of hours to a few seconds, and the multiple dimensional chromatographic-separation with various models or arrays could sufficiently separate the proteomic mixture. These advances have significantly promoted the research of protein/peptide separation and identification in proteomics.
文摘The occurrence of twin-arginine motifs （-R-R-） in the amino acid sequences of animal pro-proteins frequently defines the cleavage site（s） for their structural/functional maturation. No information is available on the presence and possible biological meaning of these motifs in the seed storage proteins. In this work, a novel endopeptidase activity with cleavage specificity to twin-arginine pairs has been detected in mature dry Lupinus albus seeds. The endopeptidase was tested with a number of endogenous and exogenous protein substrates, which were selected according to the pres- ence of one or more twin-arginine residue motifs in their amino acid sequences. The observed hydrolysis patterns were limited and highly specific. Partial proteolysis led to stable polypeptide fragments that were characterized by 1- and 2-D electrophoresis. Selected polypeptides were submitted to N-terminal amino acid sequencing and mass spectrometry anal- yses, These approaches, supported by bioinformatic analysis of the available sequences, allowed the conclusion that the polypeptide cleavage events had occurred at the peptide bonds comprised between twin-arginine residue pairs with all tested protein substrates. The endopeptidase activity was inhibited by 4-（2-AminoEthyl）Benzene-Sulphonyl Fluoride hy- drochloride （AEBSF）, leupeptin, and serine proteinase protein inhibitors, while it was not affected by pepstatin, trans- EpoxysuccinyI-L-leucylamido（4-guanidino）butane （E64）, and ethylenediaminetetraacetic acid （EDTA）, thus qualifying the Arg-Arg cleaving enzyme as a serine endopeptidase. The structural features of storage proteins from lupin and other legume seeds strongly support the hypothesis that the occurrence of an endopeptidase activity cleaving -R-R- bonds may be functional to facilitate their degradation at germination and possibly generate polypeptide fragments with specific biological activity.
文摘Liquid secondary ion mass spectrometry(LSIMS) was used to probe the proteolysis of melittin by trypsin and pepsin. The results showed that LSIMS is good for monitoring proteolytic reactions. It can not only identify the proteolytic products of proteins, but also be used to research the dynamics of proteolytic reactions. The proteolysis of melittin by trypsin gave seven main peptide fragments: 1, AA 1 AA 7 ; 2, AA 1 AA 21 ;3, AA 1 AA 22 ; 4, AA 1 AA 23 ; 5, AA 1 AA 24 ; 6, AA 8 AA 21 ; 7, AA 8 AA 22 . The proteolysis of melittin with pepsin gave thirteen peptide fragments: 1, AA 1 AA 3; 2, AA 4 AA 6;3, AA 1 AA 4;4, AA 1 AA 5 ;5, AA 1 AA 6 ;6, AA 1 AA 8;7, AA 7 AA 13 ;8, AA 10 AA 13 ;9, AA 14 AA 16 ;10, AA 14 AA 26 ;11, AA 15 AA 26 ;12, AA 17 AA 26 ;13, AA 20 AA 26 .
基金Weare grateful for the financial support from the Natural Science Foundation of China(grant nos.21778009,21977010,and 22007033)National Key Research and Development Program“Synthetic Biology”Key Special Project of China(grant no.2018YFA0902504)+3 种基金China Postdoctoral Science Foundation(grant no.2021M690220)the Natural Science Foundation of Guangdong Province(grant nos.2020A1515010522,2020A1515010766,2019A1515110487,and 2019A151-5111184)the Foundation for Basic and Applied Research of Guangdong Province(grant no.2019A1515110489)and the Shenzhen Science and Technology Innovation Committee(grant nos.JCYJ20180507181527112,JCYJ-201805081522131455,and JCYJ20170817172023838).
文摘Over the past 20 years,great efforts have been invested in developing site-specific approaches to protein modification to dissect protein functions directly and accurately.Here,we report a proximitytriggered group transfer strategy from a sulfonium warhead to a Cysteine(Cys)residue of the target protein.With a guiding ligand,cargoes could be transferred selectively from a sulfonium center onto the Cys residue in the vicinity of their binding interface.The successful thalidomide transfer of sulfonium 1-X could be applied intracellularly for epidermal growth factor receptor degradation,highlighting the potential of group transfer strategy as a suite of chemical biology studies,including cell imaging,protein profiling,and protein degradation by simply employing different transferrable groups.
基金financially supported by the National Natural Science Foundation of China(32001728,32172248)the Taishan Industrial Experts Program+1 种基金the Guizhou High-level Innovative Talent Training Project(Qianke Cooperation Platform Talent number[2016]5662)Guizhou Science and Technology Innovation Talent Team of Ecological Characteristic Meat Products.(QKHPTRC[2020]5004)。
文摘Dry-cured meat products are considerably popular around the world due to unique flavor.Proteolysis is one of the enzymatic reactions from which flavor substances are derived,which is affected by endogenous proteases.The purpose aimed to reveal the potential relationship between endogenous proteases and key flavor substances in dry-cured pork coppa in this paper.The dynamic changes of endogenous proteases activity,free amino acids,and volatiles during dry-cured pork coppa processing were characterized.The results showed that 5 kinds of free amino acids,Glu,Lys,Val,Ala,and Leu,were identified as significant contributors to taste.Meanwhile,key volatiles,such as hexanal,nonanal,octanal,benzaldehyde,3-methyl butanoic acid,2-methyl propanoic acid,and ethyl octanoate,greatly contributed to the flavor characteristics of dry-cured pork coppa.Further partial correlation analysis was performed to better elucidate the relationship among parameters.The results revealed that close relationship between endogenous proteases and key substances.RAP not only significantly affected the accumulation of key active-amino acids,but also affected the accumulation of ethyl octanoate,2,3-pentanedione,and 2,3-octanedione by regulating the accumulation of octanoic acid and Leu.In addition,cathepsin B and D,DPP II,DPP IV and RAP notably affected accumulation of hexanal.
基金supported by grants from the National Natural Science Foundation of China(32000998,32201240,and 81700638)The Young Elite Scientists Sponsorship Program by the Henan Association for Science and Technology(2022HYTP046)the China Postdoctoral Science Foundation(2021TQ0298).
文摘Leucine-richα-2 glycoprotein 1(LRG1),a secreted glycoprotein,has been identified as significantly upregulated in renal fibrosis,potentially exacerbating the condition by enhancing TGF-β-Smad3-dependent signaling pathways.Herein,utilizing our developed LRG1-targeting peptide for LRG1 recruitment and lenalidomide for E3 ubiquitin ligase engagement,we developed an advanced proteolysis targeting chimera,^(ET)TAC-2,specifically designed for LRG1 degradation.Our cellular degradation assays validated that ^(ET)TAC-2 effectively degraded LRG1 through a proteasome-dependent mechanism,achieving halfmaximal degradation at a concentration of 8.38μM.Furthermore,anti-fibrotic experiments conducted both in vitro and in vivo revealed that ^(ET)TAC-2 efficiently induced LRG1 degradation in fibrotic kidneys.This action effectively inhibited the TGF-β-Smad3 signaling pathway and diminished the secretion of fibrosis-associated proteins,consequently attenuating the progression of renal fibrosis.Our study highlights the pivotal role of LRG1 in renal fibrosis and positions ^(ET)TAC-2 as a promising therapeutic candidate for targeted LRG1 intervention.
基金funded by National Natural Science Foundation of China(21868003)Bama County Program for Talents in Science and Technology(BaRenKe20210045).
文摘The traditional nutritional and medical hemp(Cannabis sativa L.)seed protein were explored for the discovery and directional preparation of new xanthine oxidase inhibitory(XOI)peptides by structure-based virtual screening,compound synthesis,in vitro bioassay and proteolysis.Six subtypes of hemp seed edestin and albumin were in silico hydrolyzed by 29 proteases,and 192 encrypted bioactive peptides were screened out.Six peptides showed to be XOI peptides,of which four(about 67%)were released by elastase hydrolysis.The peptide DDNPRRFY displayed the highest XOI activity(IC50=(2.10±0.06)mg/mL),acting as a mixed inhibitor.The pancreatic elastase directionally prepared XOI hemp seed protein hydrolysates,from which 6 high-abundance XOI peptides encrypted 3 virtually-screened ones including the DDNPRRFY.The novel outstanding hemp seed protein-derived XOI peptides and their virtual screening and directed preparation methods provide a promising and applicable approach to conveniently and efficiently explore food-derived bioactive peptides.
基金supported by the Graduate Education Innovation and Quality Improvement Project of Henan University(No.SYLYC2023185).
文摘Sourdough is often considered a healthy choice and quality improver for use in cereal production due to its unique microbial composition and fermentation properties.During sourdough fermentation of cereals,biotransformation of nutrients occurs,resulting in notable changes to proteins,carbohydrates,fats,vitamins,and minerals.Each nutrient undergoes specific transformations,providing various advantages for human health.Proteins undergo hydrolysis to produce small molecular weight peptides and amino acids that are more easily digested and absorbed by the human body.Carbohydrates break down to improve the digestibility and absorption of cereals and lower the glycemic index.Fatty acids experience oxidation to produce new substances with health benefits.Additionally,the application of sourdough fermentation can enhance the texture,flavor,and nutritional value of cereal foods while also extending their shelf life and improving food safety.In conclusion,sourdough fermentation has a broad range of applications in cereal food processing.Further research is encouraged to investigate the mechanisms and processes of sourdough fermentation to develop even more nutritious,healthy,and flavorful cereal-based foods.
基金supported by JSPS KAKENHI Grant Number JP21KK0177 to SF.
文摘Objectives Exercise training induces several skeletal muscle adaptations.Beta-guanidinopropionic acid(β-GPA)is a creatine analog that simulates the effect of exercise to induce mitochondrial biogenesis.However,the effects ofβ-GPA on resistance training adaptation,such as muscle hypertrophy and mitochondrial biogenesis,are unclear.Therefore,using a resistance exercise model in rats,the present study was designed to investigate the effects ofβ-GPA administration on resistance training adaptations.Methods This study was approved by the Ethics Committee for Animal Experiments at Ritsumeikan University(approval number:BKC2022-009).Male Sprague Dawley rats were randomly divided into placebo orβ-GPA groups.β-GPA(1000 mg/kg)was orally administered once daily,starting seven days before the initiation of electromyostimulation as a model for resistance exercise,and continued throughout the training period.Electromyostimulation was applied to the right gastrocnemius muscle via electrical stimulation every other day for a total of 12 sessions Results Peroxisome proliferators-activated receptor-γco-activator-1α,a regulator of mitochondrial biogenesis,was significantly increased by the combination of training andβ-GPA compared to the training leg(p<0.05).Protein expression of Total OXPHOS,a marker of mitochondrial content,was significantly increased by the combination of training andβ-GPA compared to the training leg(p<0.05).β-GPA intake reduced muscle mass(main effect ofβ-GPA,p<0.05)and was associated with muscle protein breakdown-related Fbx32 and LC3-II protein expression levels but did not counteract the increase in muscle mass caused by resistance training.Conclusions Administration of exogenousβ-GPA enhanced resistance training-induced mitochondrial biogenesis.Moreover,β-GPA still permitted resistance electromyostimulation-induced muscle mass gains,but that effect was attenuated as compared to placebo.
基金Supported by the Cloning and Genetics Analysis of Cold-Induced Genes in PA64S, Natural Science Foundation of Hunan Province(09JJ3044)
文摘F-box protein is an expanding family member of eukaryotic protein characterized by an F-box motif which has specificity of substrate recognition in the ubiquitin-mediated proteolysis.These proteins have been proved to be critical for many physiological processes,such as cell-cycle transition,signal transduction,gene transcription,male sterility,programmed cell death （PCD） and so on.This paper mainly introduces the biological functions of the known F-box proteins and the analysis of F-box gene phylogeny.
文摘Macroautophagy is a multistep, vacuolar, degradation pathway terminating in the lysosomal compartment, and it is of fundamental importance in tissue homeostasis. In this review, we consider macroautophagy in the light of recent advances in our understanding of the formation of autophagosomes, which are double-membrane-bound vacuoles that sequester cytoplasmic cargos and deliver them to lysosomes. In most cases, this final step is preceded by a maturation step during which autophagosomes interact with the endocytic pathway. The discovery of AuTophaGyrelated genes has greatly increased our knowledge about the mechanism responsible for antophagosome formation, and there has also been progress in the understanding of molecular aspects of autophagosome maturation. Finally, the regulation of autophagy is now better understood because of the discovery that the activity of Atg complexes is targeted by protein kinases, and owing to the importance of nuclear regulation via transcription factors in regulating the expression of autophagy genes.
