BACKGROUND Gastric carcinoma(GC)is a common gastrointestinal malignancy worldwide.Based on the cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore...BACKGROUND Gastric carcinoma(GC)is a common gastrointestinal malignancy worldwide.Based on the cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is important to find effective drug treatment targets.AIM To explore the mechanism by which 18β-glycyrrhetinic acid(18β-GRA)regulates mitochondrial ribosomal protein L35(MRPL35)related signal proteins to inhibit the proliferation of GC cells.METHODS Cell counting kit-8 assay was used to detect the effects of 18β-GRA on the survival rate of human normal gastric mucosal cell line GES-1 and the proliferation of GC cell lines MGC80-3 and BGC-823.The apoptosis and cell cycle were assessed by flow cytometry.Cell invasion and migration were evaluated by Transwell assay,and cell scratch test was used to detect cell migration.Furthermore,a tumor model was established by hypodermic injection of 2.5×106 BGC-823 cells at the selected positions of BALB/c nude mice to determine the effect of 18β-GRA on GC cell proliferation,and quantitative reverse transcription-polymerase chain reaction(qRT-PCR)was used to detect MRPL35 expression in the engrafted tumors in mice.We used the term tandem mass tag(TMT)labeling combined with liquid chromatography–tandem mass spectrometry to screen for differentially expressed proteins(DEPs)extracted from GC cells and control cells after 18β-GRA intervention.A detailed bioinformatics analysis of these DEPs was performed,including Gene Ontology annotation and enrichment analysis,Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis,and so on.Moreover,STRING database(https://string-db.org/)was used to predict proteinprotein interaction(PPI)relationships and Western blot was used to detect the expression of proteins of interest in GC cells.RESULTS The results indicated that 18β-GRA could inhibit the proliferation of GC cells in a dose-and timedependent manner.It could induce GC cell apoptosis and arrest the cell cycle at G0/G1 phase.The proportion of cells arrested at S phase decreased with the increase of 18-GRA dose,and the migration and invasiveness of GC cells were inhibited.The results of animal experiments showed that 18β-GRA could inhibit tumor formation in BALB/c nude mice,and qRT-PCR results showed that MRPL35 expression level was significantly reduced in the engrafted tumors in mice.Using TMT technology,609 DEPs,among which 335 were up-regulated and 274 were down-regulated,were identified in 18β-GRA intervention compared with control.We found that the intervention of 18β-GRA in GC cells involved many important biological processes and signaling pathways,such as cellular processes,biological regulation,and TP53 signaling pathway.Notably,after the drug intervention,MRPL35 expression was significantly down-regulated(P=0.000247),TP53 expression was up-regulated(P=0.02676),and BCL2L1 was down-regulated(P=0.01699).Combined with the Retrieval of Interacting Genes/Proteins database,we analyzed the relationship between MRPL35,TP53,and BCL2L1 signaling proteins,and we found that COPS5,BAX,and BAD proteins can form a PPI network with MRPL35,TP53,and BCL2L1.Western blot analysis confirmed the intervention effect of 18β-GRA on GC cells,MRPL35,TP53,and BCL2L1 showed dose-dependent up/down-regulation,and the expression of COPS5,BAX,and BAD also increased/decreased with the change of 18β-GRA concentration.CONCLUSION 18β-GRA can inhibit the proliferation of GC cells by regulating MRPL35,COPS5,TP53,BCL2L1,BAX,and BAD.展开更多
Objective:Amphenicols(chloramphenicol,thiamphenicol and forfenicol)can cause aplastic anaemia and other severe side effects to consumers;therefore,it is necessary to inspect their residues in foods of animal origin.Ho...Objective:Amphenicols(chloramphenicol,thiamphenicol and forfenicol)can cause aplastic anaemia and other severe side effects to consumers;therefore,it is necessary to inspect their residues in foods of animal origin.However,there has been no report on the use of amphenicols receptor for the determination of their residues,and none of the previously reported immunoassays for amphenicols can differentiate the specifc species.Materials and Methods:In this study,the ribosomal protein L16 of Escherichia coli was frst expressed,and its intermolecular interaction mechanisms with the three amphenicols was studied using the molecular docking technique.The protein was then combined with three enzymelabelled conjugates to develop a direct competitive array on microplate for determination of the three drugs in egg.Results:Due to the use of principal component analysis to analyse the data,this method could discriminate the three drugs in the range 0.1–10 ng/mL,and the limits of detection for the three drugs were in the range of 0.0002–0.0009 ng/mL.The analysis results for the unknown egg samples were consistent with a liquid chromatography–tandem mass spectrometry method,and the method performances were superior to the previous immunoassays for amphenicols.Conclusion:This is the frst paper reporting the use of ribosomal protein L16 to develop a competitive array for discriminative determination of amphenicols in food samples.展开更多
Single-molecule magnetic tweezers(MTs) have revealed multiple transition barriers along the unfolding pathway of several two-state proteins, such as GB1 and Csp. In this study, we utilized MTs to measure the force-dep...Single-molecule magnetic tweezers(MTs) have revealed multiple transition barriers along the unfolding pathway of several two-state proteins, such as GB1 and Csp. In this study, we utilized MTs to measure the force-dependent folding and unfolding rates of both protein L(PLWT) and its Y47W mutant(PLY47W) where the mutation point is not at the force-bearing β-strands. The measurements were conducted within a force range of 3–120 pN. Notably, the unfolding rates of both PLWT and PWY47W exhibit distinct force sensitivities below 50 pN and above 60 pN, implying a two-barrier free energy landscape. Both PLWT and PLY47W share the same force-dependent folding rate and the same transition barriers,but the unfolding rate of PLY47W is faster than that of PLWT. Our finding demonstrates that the residue outside of the force-bearing region will also affect the force-induced unfolding dynamics.展开更多
Like Xenopus laeuis, some species of the Rang genus are also used to study endocrine disrupting chemicals （EDCs）. Although ribosomal protein L8 （rp18） is the most-used reference gene for analyzing gene expression ...Like Xenopus laeuis, some species of the Rang genus are also used to study endocrine disrupting chemicals （EDCs）. Although ribosomal protein L8 （rp18） is the most-used reference gene for analyzing gene expression by quantitative reverse transcription polymerase chain reaction in Rang, its suitability as the reference gene has never been validated in any species of the Rana genus. We characterized rp18 cDNA in Rana nigromaculata, a promising native species in East Asia for assaying endocrine disrupting effects. We found that the rp18 cDNA consisted of 919 bp and encoded 257 amino acids, exhibiting high identities of amino acid sequence with known rp18 in other Rana species. Then, we examined the stability of mRNA expression during development. Compared with elongation factor 1 alpha 1, another common housekeeping gene, neither stage-specific nor tissue-specific expression of the rp18 gene was found in all tissues examined （brain, liver, intestine, tail, testis and ovary） during R. nigromaculata development. Finally, we investigated rp18 expression under exposure to hormones. No change in rp18 mRNA expression was found under exposure to thyroid hormone （T4） and estrogen （estradiol）, whereas expression of the corresponding biomarker genes was induced. Our results show that rp18 is an appropriate reference gene for analyzing gene expression by quantitative reverse transcription polymerase chain reaction for assaying EDCs using R. nigromaculata, and might also provide support for using rp18 as a reference gene in other Rang species due to the high conservation of rp18 among the Rana genus.展开更多
Objective Numerous studies have indicated that excitatory amino acid toxicity,such as glutamate toxicity,is involved in glaucoma.In addition,excessive glutamate can lead to an intracellular calcium overload,resulting ...Objective Numerous studies have indicated that excitatory amino acid toxicity,such as glutamate toxicity,is involved in glaucoma.In addition,excessive glutamate can lead to an intracellular calcium overload,resulting in regulated necrosis.Our previous studies have found that the calpastatin(CAST)-calpain pathway plays an important role in retinal neuron-regulated necrosis after glutamate injury.Although inhibition of the calpain pathway can decrease regulated necrosis,necrotic cells remain.It has been suggested that there are other molecules that participate in retinal neuron-regulated necrosis.CAST is an important regulator of dynamin-related protein 1(Drp1)-mediated mitochondrial defects.Thus,the aim of this study was to determine whether the CAST-Drp1 pathway may be an underlying signaling axis in neuron-regulated necrosis.Methods Using cultured retinal neurons and in an in-vivo glaucoma model induced by glutamate overload,members of the CAST-Drp1 pathway were assessed by immunofluorescence,Western blotting,Phos-tagTM SDS-PAGE,and co-immunoprecipitation assays.Moreover,the black and white box test was performed on the rats.Results We found that more retinal neuron-regulated necrosis and Drp1 activation as well as lower CAST levels were present in the glutamate-induced glaucoma model.Rats with glutamate-induced glaucoma exhibited impaired visual function.We also observed retinal neuron-regulated necrosis and Drp1 activity decreased,and impaired vision recovered after CAST active peptide application,indicating that the CAST-Drp1 pathway plays a critical role in retinal neuron-regulated necrosis and visual function.Conclusion The results of this study indicate that the CAST-Drp1 pathway protects against retinal neuron-regulated necrosis,which may expand the therapeutic targets for the treatment of neurodegenerative disorders involving dysfunction of glutamate metabolism,such as glaucoma.展开更多
INTRODUCTIONFrom the technical aspect of liver surgery ,control of bleeding during hepatic parenchymal resection is one of the most important procedures in hepatectomy .Pringle,s maneuver ,a temporary cross-clamping ...INTRODUCTIONFrom the technical aspect of liver surgery ,control of bleeding during hepatic parenchymal resection is one of the most important procedures in hepatectomy .Pringle,s maneuver ,a temporary cross-clamping of the hepatoduodnal ligament ,has often been used for this purpose[1],This is the simplest and userul technique to reduce intraoperative blood loss .展开更多
AIM： To investigate the effect of high mobility group protein box-1 （HMGB1） siRNA on proliferation and apoptosis of retinoblastoma （Rb） cells.METHODS： The expression of HMGB1 in Rb cells were detected by real-ti...AIM： To investigate the effect of high mobility group protein box-1 （HMGB1） siRNA on proliferation and apoptosis of retinoblastoma （Rb） cells.METHODS： The expression of HMGB1 in Rb cells were detected by real-time polymerase chain reaction （RT-PCR） and Western blot. Chemically synthesized HMGB1 siRNA was transfected into Y79 cells. The inhibitory rate was also examined by RT-PCR and Western blot. After HMGB1 siRNA transfection, the cell proliferation was analyzed by MTT, and cell apoptosis was detected by Caspase-3 active detection kit. Cell cycle distribution and apoptosis were detected by flow cytometry. RESULTS： The expression of HMGB1 significantly elevated in Rb cells （P〈0.01）. After transfected by siRNA, the HMGB1 protein level of Y79 cells was significantly reduced （P〈0.01）. After siRNA interference HMGB1, the proportion of proliferating cells reduced, and the proportion of quiescent cells increased （P〈0.05）. In addition, apoptosis rate of Y79 cells increased from 2.03% to 9.10% after interfering with HMGB1 siRNA （P〈0.05）.CONCLUSION： Specific HMGB1 siRNA can inhibit the expression of HMGB1. The effect may be attributed to inhibit the proliferation and promote cell apoptosis.展开更多
In order to study the role of monocyte chemotactic protein-1 (MCP-1) in the intra-peri- toneal adhesion formation, 23 infertile patients undergoing laparoscopic operation were divided into two groups: experimental gr...In order to study the role of monocyte chemotactic protein-1 (MCP-1) in the intra-peri- toneal adhesion formation, 23 infertile patients undergoing laparoscopic operation were divided into two groups: experimental group including 12 patients with intra-peritoneal adhesion and control group including 11 patients without intra-peritoneal adhesion. Peritoneal fluid (PF) and peritoneum were collected from these patients during laparoscopic examination. The expression levels of MCP-1 protein and MCP-1 mRNA were detected by using enzyme-linked immunosorbent assay (ELISA) and dot blot analysis method respectively. It was found that the levels of MCP-l protein in PF of the patients with peritoneal adhesion were significantly higher than in the control group (0.44±0. 11 ng/ ml vs 0. 19±0.09 ng/ml respectively, P<0. 01). The level of MCP-l mRNA in the peritoneum of the patients with peritoneal adhesion was significantly higher than in the control group (48. 61±3. 72 vs 19.87±2.54 respectively, P<0. 01). It was suggested that MCP-1 might play a role in the adhe- sion formation, and chemotactic cytokines expressing in the peritoneal mesothelial cells might be take part in the process.展开更多
Summary: To prepare carboxyl terminus truncated human papillomavirus type 58 L1(HPV58L1) protein and evaluate its ability to form virus-like particles, the baculovirus and Sf-9 insect cells was used to express HPV58L1...Summary: To prepare carboxyl terminus truncated human papillomavirus type 58 L1(HPV58L1) protein and evaluate its ability to form virus-like particles, the baculovirus and Sf-9 insect cells was used to express HPV58L1 protein, and pFastBac-Htb containing HPV58L1 gene sequence of carboxyl terminus truncation was generated. Then Sf-9 cells were infected with recombinant baculovirus. After being cultured, the post-infected cells expressing-HPV58L1 protein-were harvested and analyzed by SDS-PAGE and Western blot. The ProBond~TM purification system was used for protein purification. The bio-activity of purified protein was identified by mouse erythrocyte hemagglutination assay, and the VLP formation was examined with transmission electron microscope. Our results showed that the recombinant baculovirus was generated and the Sf-9 cells was infected with the recombinant baculovirus, and after collecting, total cellular proteins were extracted. Truncated HPV58L1 protein with MW 58KD was revealed by SDS-PAGE and confirmed by Western blot. The purified L1 proteins under native condition could cause mouse erythrocytes to agglutinate and form VLP. It is concluded that HPV58L1 protein with carboxyl terminus truncation could be efficiently expressed. In baculovirus Sf-9 cells expression system, the purified protein could self-assemble into virions in vitro, and induce agglutination of mouse erythrocytes, indicating that carboxyl terminus truncation does not interfere with the bioactivity of HPV58L1 protein.展开更多
Four and a half LIM domains protein 1(FH L1),as the name suggests,contains four and a half LIM domains capable o f interacting with various molecules,including structural proteins,kinases,and transcriptional machinery...Four and a half LIM domains protein 1(FH L1),as the name suggests,contains four and a half LIM domains capable o f interacting with various molecules,including structural proteins,kinases,and transcriptional machinery.FHL1 contains a zinc-finger domain and performs diverse roles in regulation of gene transcription,cytoarchitecture,cell proliferation,and signal transduction.Several studies have validated the importance of FHL1 in muscle development,myopathy,and cardiovascular diseases.Mutations in the FHL1 gene are associated with various myopathies.Recently,FHL1 was identified as a major host factor for chikungunya virus(CHIKV)infection in both humans and mice.Based on more recent findings over the last decade,FHL1 is proposed to play a dual role in cancer progression.On the one hand,FHL1 expression is suppressed in several cancer types,which correlates with increased metastatic disease and decreased survival.Moreover,FHL1 is reported to inhibit tum or cell growth and migration by associating with diverse signals,such as TGF-P and ER,and therefore considered a tumor suppressor.On the other hand,FHL1 can function as an oncogenic protein that promotes tumor progression upon phosphorylation,reflecting complex roles in cancer.This review primarily focuses on the dual role and underlying mechanisms of action of FHL1 in human cancer progression and its clinical relevance.展开更多
Heat shock proteins (HSPs) are reported to act as effective adjuvants to elicit anti-tumor and anti-infection immunity. Here, we report that Hsp70-like protein 1 (Hsp70L1), a novel HSP derived from human dendritic cel...Heat shock proteins (HSPs) are reported to act as effective adjuvants to elicit anti-tumor and anti-infection immunity. Here, we report that Hsp70-like protein 1 (Hsp70L1), a novel HSP derived from human dendritic cells (DCs), has potent adjuvant effects that polarize responses toward Th1. With a calculated molecular weight of 54.8 kDa, Hsp70L1 is smaller in size than Hsp70 but resembles it both structurally and functionally. Hsp70L1 shares common receptors on DCs with Hsp70 and can interact with DCs, promoting DC maturation and stimulating secretion of the proinflammatory cytokines interleukin 12p70 (IL-12p70), IL-1beta, tumor necrosis factor-alpha (TNF-alpha), and the chemokines IP-10, macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, and normal T cell expressed and secreted (RANTES). The induction of interferon-gamma-inducible protein 10 (IP-10) secretion by Hsp70L1 is not shared by Hsp70, and other functional differences include more potent stimulation of DC IL-12p70, CC-chemokine, and CCR7 and CXCR4 expression by Hsp70L1. Immunization of mice with the hybrid peptide Hsp70L1-ovalbumin(OVA)(257-264) induces an OVA(257-264)-specific Th1 response and cytotoxic T lymphocyte (CTL) that results in significant inhibition of E.G7-OVA tumor growth. The ability of Hsp70L1 to activate DCs indicates its potential as a novel adjuvant for use with peptide immunizations; the Hsp70L1 antigen peptide hybrid may serve as a more effective vaccine for the control of cancer and infectious diseases.展开更多
The near infrared spectra of 178 recombinant inbred lines （RILs） from the cross of Ⅱ-32B/Yuezaoxian 6 （YZX6） and 511 varieties in rice were acquired. A total of 80 RILs and 96 cultivars were selected as modeling ...The near infrared spectra of 178 recombinant inbred lines （RILs） from the cross of Ⅱ-32B/Yuezaoxian 6 （YZX6） and 511 varieties in rice were acquired. A total of 80 RILs and 96 cultivars were selected as modeling samples by comparing the spectra similarity primarily. Three partial least square （PLS） regression models were developed, based on the RILs （RIL-model）, the varieties （Var-model） and their mixture （Mix-model）, for protein content （PC） and amylose content （AC）, respectively. Cross validation and outer prediction showed that the models were largely influenced by the range and distribution of modeling samples. The regression model of PC based on the cultivars and the model of AC based on RILs had higher coefficient of determination （r^2 ≥ 0.9） and lower root mean square error of cross validation （RMSECVs）. The disadvantages of RIL samples for PC model and variety samples for AC model were probably caused by the narrow range of variance. Aberrant predictions were obtained for outer sample with PC or AC outside the range or within the distribution gap of modeling samples. The Mix-models gave more reliable prediction as the distribution of RIL and variety modeling samples were complementary to each other.展开更多
The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring （cv. Kohdasht） and two winter （cvs. Sardari and Norstar） cul...The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring （cv. Kohdasht） and two winter （cvs. Sardari and Norstar） cultivars of wheat （Triticum aestivum L.） exposed to 4℃. Plants were sampled on days 2, 14, 21 and 35 of exposure to 4℃. The final leaf number （FLN） was determined throughout the vernalization periods （0, 7, 14, 24, and 35 d） at 4℃. The final leaf number decreased until days 24 and 35 in Sardari and Norstar eultivars, respectively, indicating the vernalization saturation at these times. No clear changes were detected in the final leaf number of Kohdash cultivar, verifying no vernalization requirement for this spring wheat cultivar. Comparing with control, clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4℃-treatment in the leaves of the both winter wheat cultivars but, such response was not detected in the spring cultivar. However, the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences. With increasing exposure time to 4℃, the winter cultivars tended to produce more HMW polypeptides than the spring cultivar. Similar proteins were induced in both Sardari and Norstar winter wheat cultivars, however, the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement. These observations indicate that vernalization response regulates the expression of low temperature （LT） tolerance proteins and determines the duration of expression of LT- induced proteins.展开更多
基金Supported by Ningxia Natural Science Foundation,No.2020AAC03130Ningxia Medical University Project,No.XM2020005.
文摘BACKGROUND Gastric carcinoma(GC)is a common gastrointestinal malignancy worldwide.Based on the cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is important to find effective drug treatment targets.AIM To explore the mechanism by which 18β-glycyrrhetinic acid(18β-GRA)regulates mitochondrial ribosomal protein L35(MRPL35)related signal proteins to inhibit the proliferation of GC cells.METHODS Cell counting kit-8 assay was used to detect the effects of 18β-GRA on the survival rate of human normal gastric mucosal cell line GES-1 and the proliferation of GC cell lines MGC80-3 and BGC-823.The apoptosis and cell cycle were assessed by flow cytometry.Cell invasion and migration were evaluated by Transwell assay,and cell scratch test was used to detect cell migration.Furthermore,a tumor model was established by hypodermic injection of 2.5×106 BGC-823 cells at the selected positions of BALB/c nude mice to determine the effect of 18β-GRA on GC cell proliferation,and quantitative reverse transcription-polymerase chain reaction(qRT-PCR)was used to detect MRPL35 expression in the engrafted tumors in mice.We used the term tandem mass tag(TMT)labeling combined with liquid chromatography–tandem mass spectrometry to screen for differentially expressed proteins(DEPs)extracted from GC cells and control cells after 18β-GRA intervention.A detailed bioinformatics analysis of these DEPs was performed,including Gene Ontology annotation and enrichment analysis,Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis,and so on.Moreover,STRING database(https://string-db.org/)was used to predict proteinprotein interaction(PPI)relationships and Western blot was used to detect the expression of proteins of interest in GC cells.RESULTS The results indicated that 18β-GRA could inhibit the proliferation of GC cells in a dose-and timedependent manner.It could induce GC cell apoptosis and arrest the cell cycle at G0/G1 phase.The proportion of cells arrested at S phase decreased with the increase of 18-GRA dose,and the migration and invasiveness of GC cells were inhibited.The results of animal experiments showed that 18β-GRA could inhibit tumor formation in BALB/c nude mice,and qRT-PCR results showed that MRPL35 expression level was significantly reduced in the engrafted tumors in mice.Using TMT technology,609 DEPs,among which 335 were up-regulated and 274 were down-regulated,were identified in 18β-GRA intervention compared with control.We found that the intervention of 18β-GRA in GC cells involved many important biological processes and signaling pathways,such as cellular processes,biological regulation,and TP53 signaling pathway.Notably,after the drug intervention,MRPL35 expression was significantly down-regulated(P=0.000247),TP53 expression was up-regulated(P=0.02676),and BCL2L1 was down-regulated(P=0.01699).Combined with the Retrieval of Interacting Genes/Proteins database,we analyzed the relationship between MRPL35,TP53,and BCL2L1 signaling proteins,and we found that COPS5,BAX,and BAD proteins can form a PPI network with MRPL35,TP53,and BCL2L1.Western blot analysis confirmed the intervention effect of 18β-GRA on GC cells,MRPL35,TP53,and BCL2L1 showed dose-dependent up/down-regulation,and the expression of COPS5,BAX,and BAD also increased/decreased with the change of 18β-GRA concentration.CONCLUSION 18β-GRA can inhibit the proliferation of GC cells by regulating MRPL35,COPS5,TP53,BCL2L1,BAX,and BAD.
基金the National Natural Science Foundation of China(No.32372447)the Natural Science Foundation of Hebei Province(No.C2023204045),China.
文摘Objective:Amphenicols(chloramphenicol,thiamphenicol and forfenicol)can cause aplastic anaemia and other severe side effects to consumers;therefore,it is necessary to inspect their residues in foods of animal origin.However,there has been no report on the use of amphenicols receptor for the determination of their residues,and none of the previously reported immunoassays for amphenicols can differentiate the specifc species.Materials and Methods:In this study,the ribosomal protein L16 of Escherichia coli was frst expressed,and its intermolecular interaction mechanisms with the three amphenicols was studied using the molecular docking technique.The protein was then combined with three enzymelabelled conjugates to develop a direct competitive array on microplate for determination of the three drugs in egg.Results:Due to the use of principal component analysis to analyse the data,this method could discriminate the three drugs in the range 0.1–10 ng/mL,and the limits of detection for the three drugs were in the range of 0.0002–0.0009 ng/mL.The analysis results for the unknown egg samples were consistent with a liquid chromatography–tandem mass spectrometry method,and the method performances were superior to the previous immunoassays for amphenicols.Conclusion:This is the frst paper reporting the use of ribosomal protein L16 to develop a competitive array for discriminative determination of amphenicols in food samples.
基金supported by the National Natural Science Foundation of China(Grant Nos.12174322 to HC and 12204124 to ZG)111 Project(Grant No.B16029)+1 种基金the Graduate Scientific Research Foundation of Wenzhou University(Grant No.3162023003034 to JH)research grant from Wenzhou Institute。
文摘Single-molecule magnetic tweezers(MTs) have revealed multiple transition barriers along the unfolding pathway of several two-state proteins, such as GB1 and Csp. In this study, we utilized MTs to measure the force-dependent folding and unfolding rates of both protein L(PLWT) and its Y47W mutant(PLY47W) where the mutation point is not at the force-bearing β-strands. The measurements were conducted within a force range of 3–120 pN. Notably, the unfolding rates of both PLWT and PWY47W exhibit distinct force sensitivities below 50 pN and above 60 pN, implying a two-barrier free energy landscape. Both PLWT and PLY47W share the same force-dependent folding rate and the same transition barriers,but the unfolding rate of PLY47W is faster than that of PLWT. Our finding demonstrates that the residue outside of the force-bearing region will also affect the force-induced unfolding dynamics.
基金supported by the National High Technology Research and Development Program (863) of China (No. 2012AA06A302)the Public Welfare Research Project for Environmental Protection (No. 201109048)the National Natural Science Foundation of China (No. 21077125)
文摘Like Xenopus laeuis, some species of the Rang genus are also used to study endocrine disrupting chemicals （EDCs）. Although ribosomal protein L8 （rp18） is the most-used reference gene for analyzing gene expression by quantitative reverse transcription polymerase chain reaction in Rang, its suitability as the reference gene has never been validated in any species of the Rana genus. We characterized rp18 cDNA in Rana nigromaculata, a promising native species in East Asia for assaying endocrine disrupting effects. We found that the rp18 cDNA consisted of 919 bp and encoded 257 amino acids, exhibiting high identities of amino acid sequence with known rp18 in other Rana species. Then, we examined the stability of mRNA expression during development. Compared with elongation factor 1 alpha 1, another common housekeeping gene, neither stage-specific nor tissue-specific expression of the rp18 gene was found in all tissues examined （brain, liver, intestine, tail, testis and ovary） during R. nigromaculata development. Finally, we investigated rp18 expression under exposure to hormones. No change in rp18 mRNA expression was found under exposure to thyroid hormone （T4） and estrogen （estradiol）, whereas expression of the corresponding biomarker genes was induced. Our results show that rp18 is an appropriate reference gene for analyzing gene expression by quantitative reverse transcription polymerase chain reaction for assaying EDCs using R. nigromaculata, and might also provide support for using rp18 as a reference gene in other Rang species due to the high conservation of rp18 among the Rana genus.
基金supported by the National Natural Science Foundation of China(No.82101126)the Natural Science Foundation of Hunan Province(No.2021JJ40873).
文摘Objective Numerous studies have indicated that excitatory amino acid toxicity,such as glutamate toxicity,is involved in glaucoma.In addition,excessive glutamate can lead to an intracellular calcium overload,resulting in regulated necrosis.Our previous studies have found that the calpastatin(CAST)-calpain pathway plays an important role in retinal neuron-regulated necrosis after glutamate injury.Although inhibition of the calpain pathway can decrease regulated necrosis,necrotic cells remain.It has been suggested that there are other molecules that participate in retinal neuron-regulated necrosis.CAST is an important regulator of dynamin-related protein 1(Drp1)-mediated mitochondrial defects.Thus,the aim of this study was to determine whether the CAST-Drp1 pathway may be an underlying signaling axis in neuron-regulated necrosis.Methods Using cultured retinal neurons and in an in-vivo glaucoma model induced by glutamate overload,members of the CAST-Drp1 pathway were assessed by immunofluorescence,Western blotting,Phos-tagTM SDS-PAGE,and co-immunoprecipitation assays.Moreover,the black and white box test was performed on the rats.Results We found that more retinal neuron-regulated necrosis and Drp1 activation as well as lower CAST levels were present in the glutamate-induced glaucoma model.Rats with glutamate-induced glaucoma exhibited impaired visual function.We also observed retinal neuron-regulated necrosis and Drp1 activity decreased,and impaired vision recovered after CAST active peptide application,indicating that the CAST-Drp1 pathway plays a critical role in retinal neuron-regulated necrosis and visual function.Conclusion The results of this study indicate that the CAST-Drp1 pathway protects against retinal neuron-regulated necrosis,which may expand the therapeutic targets for the treatment of neurodegenerative disorders involving dysfunction of glutamate metabolism,such as glaucoma.
基金This work was supported partly by Grant 90089102 from the Scientific Research Fund of the Ministry of Education,Japan
文摘INTRODUCTIONFrom the technical aspect of liver surgery ,control of bleeding during hepatic parenchymal resection is one of the most important procedures in hepatectomy .Pringle,s maneuver ,a temporary cross-clamping of the hepatoduodnal ligament ,has often been used for this purpose[1],This is the simplest and userul technique to reduce intraoperative blood loss .
文摘AIM： To investigate the effect of high mobility group protein box-1 （HMGB1） siRNA on proliferation and apoptosis of retinoblastoma （Rb） cells.METHODS： The expression of HMGB1 in Rb cells were detected by real-time polymerase chain reaction （RT-PCR） and Western blot. Chemically synthesized HMGB1 siRNA was transfected into Y79 cells. The inhibitory rate was also examined by RT-PCR and Western blot. After HMGB1 siRNA transfection, the cell proliferation was analyzed by MTT, and cell apoptosis was detected by Caspase-3 active detection kit. Cell cycle distribution and apoptosis were detected by flow cytometry. RESULTS： The expression of HMGB1 significantly elevated in Rb cells （P〈0.01）. After transfected by siRNA, the HMGB1 protein level of Y79 cells was significantly reduced （P〈0.01）. After siRNA interference HMGB1, the proportion of proliferating cells reduced, and the proportion of quiescent cells increased （P〈0.05）. In addition, apoptosis rate of Y79 cells increased from 2.03% to 9.10% after interfering with HMGB1 siRNA （P〈0.05）.CONCLUSION： Specific HMGB1 siRNA can inhibit the expression of HMGB1. The effect may be attributed to inhibit the proliferation and promote cell apoptosis.
文摘In order to study the role of monocyte chemotactic protein-1 (MCP-1) in the intra-peri- toneal adhesion formation, 23 infertile patients undergoing laparoscopic operation were divided into two groups: experimental group including 12 patients with intra-peritoneal adhesion and control group including 11 patients without intra-peritoneal adhesion. Peritoneal fluid (PF) and peritoneum were collected from these patients during laparoscopic examination. The expression levels of MCP-1 protein and MCP-1 mRNA were detected by using enzyme-linked immunosorbent assay (ELISA) and dot blot analysis method respectively. It was found that the levels of MCP-l protein in PF of the patients with peritoneal adhesion were significantly higher than in the control group (0.44±0. 11 ng/ ml vs 0. 19±0.09 ng/ml respectively, P<0. 01). The level of MCP-l mRNA in the peritoneum of the patients with peritoneal adhesion was significantly higher than in the control group (48. 61±3. 72 vs 19.87±2.54 respectively, P<0. 01). It was suggested that MCP-1 might play a role in the adhe- sion formation, and chemotactic cytokines expressing in the peritoneal mesothelial cells might be take part in the process.
文摘Summary: To prepare carboxyl terminus truncated human papillomavirus type 58 L1(HPV58L1) protein and evaluate its ability to form virus-like particles, the baculovirus and Sf-9 insect cells was used to express HPV58L1 protein, and pFastBac-Htb containing HPV58L1 gene sequence of carboxyl terminus truncation was generated. Then Sf-9 cells were infected with recombinant baculovirus. After being cultured, the post-infected cells expressing-HPV58L1 protein-were harvested and analyzed by SDS-PAGE and Western blot. The ProBond~TM purification system was used for protein purification. The bio-activity of purified protein was identified by mouse erythrocyte hemagglutination assay, and the VLP formation was examined with transmission electron microscope. Our results showed that the recombinant baculovirus was generated and the Sf-9 cells was infected with the recombinant baculovirus, and after collecting, total cellular proteins were extracted. Truncated HPV58L1 protein with MW 58KD was revealed by SDS-PAGE and confirmed by Western blot. The purified L1 proteins under native condition could cause mouse erythrocytes to agglutinate and form VLP. It is concluded that HPV58L1 protein with carboxyl terminus truncation could be efficiently expressed. In baculovirus Sf-9 cells expression system, the purified protein could self-assemble into virions in vitro, and induce agglutination of mouse erythrocytes, indicating that carboxyl terminus truncation does not interfere with the bioactivity of HPV58L1 protein.
基金grants from the National Natural Science Foundation of China(Grant No.81730071,81472734,and 81670626)Ministry of Science and Technology of China(Grant No.2016YFC1302103,and 2015CB553906)+1 种基金Beijing Natural Science Foundation grants(Grant No.7171005,7202084,and 7202080)Peking University grants(Grant No.BMU2018JC004 and BMU20120314)to H.Z.
文摘Four and a half LIM domains protein 1(FH L1),as the name suggests,contains four and a half LIM domains capable o f interacting with various molecules,including structural proteins,kinases,and transcriptional machinery.FHL1 contains a zinc-finger domain and performs diverse roles in regulation of gene transcription,cytoarchitecture,cell proliferation,and signal transduction.Several studies have validated the importance of FHL1 in muscle development,myopathy,and cardiovascular diseases.Mutations in the FHL1 gene are associated with various myopathies.Recently,FHL1 was identified as a major host factor for chikungunya virus(CHIKV)infection in both humans and mice.Based on more recent findings over the last decade,FHL1 is proposed to play a dual role in cancer progression.On the one hand,FHL1 expression is suppressed in several cancer types,which correlates with increased metastatic disease and decreased survival.Moreover,FHL1 is reported to inhibit tum or cell growth and migration by associating with diverse signals,such as TGF-P and ER,and therefore considered a tumor suppressor.On the other hand,FHL1 can function as an oncogenic protein that promotes tumor progression upon phosphorylation,reflecting complex roles in cancer.This review primarily focuses on the dual role and underlying mechanisms of action of FHL1 in human cancer progression and its clinical relevance.
文摘Heat shock proteins (HSPs) are reported to act as effective adjuvants to elicit anti-tumor and anti-infection immunity. Here, we report that Hsp70-like protein 1 (Hsp70L1), a novel HSP derived from human dendritic cells (DCs), has potent adjuvant effects that polarize responses toward Th1. With a calculated molecular weight of 54.8 kDa, Hsp70L1 is smaller in size than Hsp70 but resembles it both structurally and functionally. Hsp70L1 shares common receptors on DCs with Hsp70 and can interact with DCs, promoting DC maturation and stimulating secretion of the proinflammatory cytokines interleukin 12p70 (IL-12p70), IL-1beta, tumor necrosis factor-alpha (TNF-alpha), and the chemokines IP-10, macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, and normal T cell expressed and secreted (RANTES). The induction of interferon-gamma-inducible protein 10 (IP-10) secretion by Hsp70L1 is not shared by Hsp70, and other functional differences include more potent stimulation of DC IL-12p70, CC-chemokine, and CCR7 and CXCR4 expression by Hsp70L1. Immunization of mice with the hybrid peptide Hsp70L1-ovalbumin(OVA)(257-264) induces an OVA(257-264)-specific Th1 response and cytotoxic T lymphocyte (CTL) that results in significant inhibition of E.G7-OVA tumor growth. The ability of Hsp70L1 to activate DCs indicates its potential as a novel adjuvant for use with peptide immunizations; the Hsp70L1 antigen peptide hybrid may serve as a more effective vaccine for the control of cancer and infectious diseases.
文摘The near infrared spectra of 178 recombinant inbred lines （RILs） from the cross of Ⅱ-32B/Yuezaoxian 6 （YZX6） and 511 varieties in rice were acquired. A total of 80 RILs and 96 cultivars were selected as modeling samples by comparing the spectra similarity primarily. Three partial least square （PLS） regression models were developed, based on the RILs （RIL-model）, the varieties （Var-model） and their mixture （Mix-model）, for protein content （PC） and amylose content （AC）, respectively. Cross validation and outer prediction showed that the models were largely influenced by the range and distribution of modeling samples. The regression model of PC based on the cultivars and the model of AC based on RILs had higher coefficient of determination （r^2 ≥ 0.9） and lower root mean square error of cross validation （RMSECVs）. The disadvantages of RIL samples for PC model and variety samples for AC model were probably caused by the narrow range of variance. Aberrant predictions were obtained for outer sample with PC or AC outside the range or within the distribution gap of modeling samples. The Mix-models gave more reliable prediction as the distribution of RIL and variety modeling samples were complementary to each other.
基金financially supported by a grant from Tarbiat Modares University,Tehran,Iran
文摘The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring （cv. Kohdasht） and two winter （cvs. Sardari and Norstar） cultivars of wheat （Triticum aestivum L.） exposed to 4℃. Plants were sampled on days 2, 14, 21 and 35 of exposure to 4℃. The final leaf number （FLN） was determined throughout the vernalization periods （0, 7, 14, 24, and 35 d） at 4℃. The final leaf number decreased until days 24 and 35 in Sardari and Norstar eultivars, respectively, indicating the vernalization saturation at these times. No clear changes were detected in the final leaf number of Kohdash cultivar, verifying no vernalization requirement for this spring wheat cultivar. Comparing with control, clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4℃-treatment in the leaves of the both winter wheat cultivars but, such response was not detected in the spring cultivar. However, the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences. With increasing exposure time to 4℃, the winter cultivars tended to produce more HMW polypeptides than the spring cultivar. Similar proteins were induced in both Sardari and Norstar winter wheat cultivars, however, the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement. These observations indicate that vernalization response regulates the expression of low temperature （LT） tolerance proteins and determines the duration of expression of LT- induced proteins.
