Objective: To explore the underlying molecular mechanisms of cellular response to the challenge by 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis of PC12 cells, an in vitro cell model for Parkinson’s disease, a...Objective: To explore the underlying molecular mechanisms of cellular response to the challenge by 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis of PC12 cells, an in vitro cell model for Parkinson’s disease, and the effect of NF-κB activation on the protection of Parkinson’s disease by Isoflavone (I). Methods: PC12 cells were used to establish the cell model of Parkinson’s disease, and are divided into five groups: control group;MPP+ group;I (Isoflavone) + MPP+ group;I group;SN-50 + MPP+ group. The content of NF-κB in PC12 cells was determined by immunocytochemistry;The viability of PC12 cells after treated with cell-permeable NF-κB inhibitor SN-50 and cell viability were measured by MTT assay;the expression levels of NF-κB p65 in cytoplasm and nuclear fractions were evaluated by western blot analysis;the mRNA expression of NF-κB p65 was analyzed by in situ hybridization (ISH). Results: Compared with the control group, the protein of NF-κB p65 both in cytoplasm and in nuclei was significantly higher than in I + MPP+ and MPP+ groups;similarly, the mRNA expression level of NF-κB p65 gene was also significantly higher;moreover, the protein expression of NF-κB p65 was much lower in I group (P + group, the protein of NF-κB p65 was significantly lower in I + MPP+ group, the mRNA expression level of NF-κB p65 gene was also significantly lower, and the protein expression level of NF-κB p65 was much lower in I + MPP+ group (P + group (P > 0.05). Conclusion: NF-κB activation is essential to MPP+-induced apoptosis in PC12 cells;but Isoflavone can inhibit the cell damage to some extent to execute its protective function, which may be involved in nigral neurodegeneration in patients with Parkinson’s disease.展开更多
The present study characterized the nerve growth factor (NGF)-mediated regulation of tau protein expression and transcription in IMR32 human neuroblastoma cells. Treatment of IMR32 cells with 50 ng/mL NGF resulted in ...The present study characterized the nerve growth factor (NGF)-mediated regulation of tau protein expression and transcription in IMR32 human neuroblastoma cells. Treatment of IMR32 cells with 50 ng/mL NGF resulted in increased levels of specific tau protein isoforms. A 550 bp fragment of the tau promoter was cloned and treatment of transfected IMR32 and PC12 cells with NGF also resulted in increased promoter activation, suggesting that the NGF-mediated increase in tau isoforms is regulated, at least in part, at the level of transcription. Pretreatment with the MAP kinase inhibitor U0126 or the PKC inhibitor bisindolylmaleimide 1 (BIS-1) attenuated the NGF-mediated increase in tau transcription, indicating that the NGF-mediated activation of the MAP kinase and PKC signaling pathways modulate tau transcription. Pre-treatment of cells with the Akt inhibitor, LY294002 or with NOS inhibitors Nω-nitro-L-arginine methylester (L-NAME) or s-methylisothiourea (S-MIU) had no effect on the NGF-mediated increase in tau promoter activation, suggesting that NO and the NGF-Akt signaling pathway do not modulate tau transcription. Taken together, these data demonstrate that NGF increases the levels of multiple human tau isoforms in IMR32 cells which may result, at least in part, from NGF-mediated PKC and MAP kinase-induced tau transcription.展开更多
Background:Osteosarcoma is the most common primary bone malignancy,with a strong tendency towards local invasion and metastasis.The SRY-Box Transcription Factor 1(SOX1)gene,a member of the HMG-box family of DNA-bindin...Background:Osteosarcoma is the most common primary bone malignancy,with a strong tendency towards local invasion and metastasis.The SRY-Box Transcription Factor 1(SOX1)gene,a member of the HMG-box family of DNA-binding transcription factors,plays a crucial role in embryogenesis and tumorigenesis.However,its role in osteosarcoma,particularly in relation to metastatic potential,is not well understood.Methods:The GSE14359 dataset containing five samples of conventional osteosarcoma and four samples of lung metastatic osteosarcoma was obtained from the Gene Expression Omnibus(GEO)database and analyzed for differential gene expression using the R language.Gene expression was detected using qPCR and Western blotting.Transcriptional activity was assessed by Luciferase reporter gene assays,and cell metastatic ability was assessed by migration and invasion assays.Results:The study demonstrated that SOX1 binds to a specific response element within the Transmembrane 4 Superfamily Member 12(TSPAN12)promoter,upregulating TSPAN12 and its associated inflammatory pathways.Silencing TSPAN12 markedly reduces SOX1-mediated osteosarcoma cell invasion and inflammatory response,while TSPAN12 overexpression reverses these effects in SOX1-suppressed cells.Conclusion:In this study,our findings elucidate SOX1’s role in enhancing osteosarcoma metastasis via TSPAN12 upregulation,offering new insights into the molecular mechanisms of osteosarcoma progression.展开更多
The pathogen Cytospora chrysosperma is the causal agent of poplar canker disease and causes considerable economic losses in China.Mitogen-activated protein kinase(MAPK)cascades play a crucial role in mediating cellula...The pathogen Cytospora chrysosperma is the causal agent of poplar canker disease and causes considerable economic losses in China.Mitogen-activated protein kinase(MAPK)cascades play a crucial role in mediating cellular responses and Pmk1-MAPKs are indispensable for pathogenic related processes in plant pathogenic fungi.In previous studies,we demonstrated that the CcPmk1 acts as a core regulator of fungal pathogenicity by modulating a small number of master downstream targets,such as CcSte12.In this study,we identified and characterized two upstream components of CcPmk1:MAPKKK CcSte11 and MAPKK CcSte7.Deletion of CcSte11 and CcSte7,resulted in slowed growth,loss of sporulation and virulence,similar to the defects observed in the CcPmk1 deletion mutant.In addition,CcSte11,CcSte7 and CcPmk1 interact with each other,and the upstream adaptor protein CcSte50 interact with CcSte11 and CcSte7.Moreover,we explored the global regulation network of CcSte12 by transcriptional analysis between CcSte12 deletion mutants and wild-type during the simulated infection process.Two hydrolase activity GO terms(GO:0004553 and GO:0016798)and starch and sucrose metabolism(mgr00500)KEGG pathway were significantly enriched in the down-regulated genes of CcSte12 deletion mutants.In addition,a subset of glycosyl hydrolase genes and putative effector genes were significantly down-regulated in the CcSte12 deletion mutant,which might be important for fungal pathogenicity.Especially,CcSte12 bound to the CcSp84 promoter region containing the TGA AAC A motif.Moreover,comparison of CcSte12-regulated genes with CcPmk1-regulated genes revealed 116 overlapping regulated genes in both CcSte12 and CcPmk1,including some virulence-associated genes.Taken together,the protein complexes CcSte11-CcSte7-CcPmk1 receive signals transmitted by upstream CcSte50 and transmit signals to downstream CcSte12,which regulates hydrolase,effectors and other genes to promote virulence.Overall,these results indicate that the CcPmk1-MAPK signaling pathway of C.chrysosperma plays a key role in the pathogenicity.展开更多
Calcium-dependent protein kinases(CDPKs/CPKs)are key regulators of plant stress signaling that translate calcium signals into cellular responses by phosphorylating diverse substrate proteins.However,the molecular mech...Calcium-dependent protein kinases(CDPKs/CPKs)are key regulators of plant stress signaling that translate calcium signals into cellular responses by phosphorylating diverse substrate proteins.However,the molecular mechanism by which plant cells relay calcium signals in response to hypoxia remains elusive.Here,we show that one member of the CDPK family in Arabidopsis thaliana,CPK12,is rapidly activated during hypoxia through calcium-dependent phosphorylation of its Ser-186 residue.Phosphorylated CPK12 shuttles from the cytoplasm to the nucleus,where it interacts with and phosphorylates the group Ⅶ ethylene-responsive transcription factors(ERF-Ⅶ)that are core regulators of plant hypoxia sensing,to enhance their stabilities.Consistently,CPK12 knockdown lines show attenuated tolerance of hypoxia,whereas transgenic plants overexpressing CPK12 display improved hypoxia tolerance.Nonethelss,loss of function of five ERF-Ⅶ proteins in an erf-vii pentuple mutant could partially suppress the enhanced hypoxia-tolerance phenotype of CPK12-overexpressing lines.Moreover,we also discovered that phosphatidic acid and 14-3-3κ protein serve as positive and negative modulators of the CPK12 cytoplasm-to-nucleus translocation,respectively.Taken together,these findings uncover a CPK12-ERF-Ⅶ regulatory module that is key to transducing calcium signals from the cytoplasm into the nucleus to potentiate hypoxia sensing in plants.展开更多
文摘Objective: To explore the underlying molecular mechanisms of cellular response to the challenge by 1-methyl-4-phenylpyridinium (MPP+)-induced apoptosis of PC12 cells, an in vitro cell model for Parkinson’s disease, and the effect of NF-κB activation on the protection of Parkinson’s disease by Isoflavone (I). Methods: PC12 cells were used to establish the cell model of Parkinson’s disease, and are divided into five groups: control group;MPP+ group;I (Isoflavone) + MPP+ group;I group;SN-50 + MPP+ group. The content of NF-κB in PC12 cells was determined by immunocytochemistry;The viability of PC12 cells after treated with cell-permeable NF-κB inhibitor SN-50 and cell viability were measured by MTT assay;the expression levels of NF-κB p65 in cytoplasm and nuclear fractions were evaluated by western blot analysis;the mRNA expression of NF-κB p65 was analyzed by in situ hybridization (ISH). Results: Compared with the control group, the protein of NF-κB p65 both in cytoplasm and in nuclei was significantly higher than in I + MPP+ and MPP+ groups;similarly, the mRNA expression level of NF-κB p65 gene was also significantly higher;moreover, the protein expression of NF-κB p65 was much lower in I group (P + group, the protein of NF-κB p65 was significantly lower in I + MPP+ group, the mRNA expression level of NF-κB p65 gene was also significantly lower, and the protein expression level of NF-κB p65 was much lower in I + MPP+ group (P + group (P > 0.05). Conclusion: NF-κB activation is essential to MPP+-induced apoptosis in PC12 cells;but Isoflavone can inhibit the cell damage to some extent to execute its protective function, which may be involved in nigral neurodegeneration in patients with Parkinson’s disease.
文摘The present study characterized the nerve growth factor (NGF)-mediated regulation of tau protein expression and transcription in IMR32 human neuroblastoma cells. Treatment of IMR32 cells with 50 ng/mL NGF resulted in increased levels of specific tau protein isoforms. A 550 bp fragment of the tau promoter was cloned and treatment of transfected IMR32 and PC12 cells with NGF also resulted in increased promoter activation, suggesting that the NGF-mediated increase in tau isoforms is regulated, at least in part, at the level of transcription. Pretreatment with the MAP kinase inhibitor U0126 or the PKC inhibitor bisindolylmaleimide 1 (BIS-1) attenuated the NGF-mediated increase in tau transcription, indicating that the NGF-mediated activation of the MAP kinase and PKC signaling pathways modulate tau transcription. Pre-treatment of cells with the Akt inhibitor, LY294002 or with NOS inhibitors Nω-nitro-L-arginine methylester (L-NAME) or s-methylisothiourea (S-MIU) had no effect on the NGF-mediated increase in tau promoter activation, suggesting that NO and the NGF-Akt signaling pathway do not modulate tau transcription. Taken together, these data demonstrate that NGF increases the levels of multiple human tau isoforms in IMR32 cells which may result, at least in part, from NGF-mediated PKC and MAP kinase-induced tau transcription.
文摘Background:Osteosarcoma is the most common primary bone malignancy,with a strong tendency towards local invasion and metastasis.The SRY-Box Transcription Factor 1(SOX1)gene,a member of the HMG-box family of DNA-binding transcription factors,plays a crucial role in embryogenesis and tumorigenesis.However,its role in osteosarcoma,particularly in relation to metastatic potential,is not well understood.Methods:The GSE14359 dataset containing five samples of conventional osteosarcoma and four samples of lung metastatic osteosarcoma was obtained from the Gene Expression Omnibus(GEO)database and analyzed for differential gene expression using the R language.Gene expression was detected using qPCR and Western blotting.Transcriptional activity was assessed by Luciferase reporter gene assays,and cell metastatic ability was assessed by migration and invasion assays.Results:The study demonstrated that SOX1 binds to a specific response element within the Transmembrane 4 Superfamily Member 12(TSPAN12)promoter,upregulating TSPAN12 and its associated inflammatory pathways.Silencing TSPAN12 markedly reduces SOX1-mediated osteosarcoma cell invasion and inflammatory response,while TSPAN12 overexpression reverses these effects in SOX1-suppressed cells.Conclusion:In this study,our findings elucidate SOX1’s role in enhancing osteosarcoma metastasis via TSPAN12 upregulation,offering new insights into the molecular mechanisms of osteosarcoma progression.
基金supported by This work was supported by the National Key Research and Development Program(2022YFD1401003)the Fundamental Research Funds for the Central Universities(2021ZY15)the National Natural Science Foundation of China(31800540)。
文摘The pathogen Cytospora chrysosperma is the causal agent of poplar canker disease and causes considerable economic losses in China.Mitogen-activated protein kinase(MAPK)cascades play a crucial role in mediating cellular responses and Pmk1-MAPKs are indispensable for pathogenic related processes in plant pathogenic fungi.In previous studies,we demonstrated that the CcPmk1 acts as a core regulator of fungal pathogenicity by modulating a small number of master downstream targets,such as CcSte12.In this study,we identified and characterized two upstream components of CcPmk1:MAPKKK CcSte11 and MAPKK CcSte7.Deletion of CcSte11 and CcSte7,resulted in slowed growth,loss of sporulation and virulence,similar to the defects observed in the CcPmk1 deletion mutant.In addition,CcSte11,CcSte7 and CcPmk1 interact with each other,and the upstream adaptor protein CcSte50 interact with CcSte11 and CcSte7.Moreover,we explored the global regulation network of CcSte12 by transcriptional analysis between CcSte12 deletion mutants and wild-type during the simulated infection process.Two hydrolase activity GO terms(GO:0004553 and GO:0016798)and starch and sucrose metabolism(mgr00500)KEGG pathway were significantly enriched in the down-regulated genes of CcSte12 deletion mutants.In addition,a subset of glycosyl hydrolase genes and putative effector genes were significantly down-regulated in the CcSte12 deletion mutant,which might be important for fungal pathogenicity.Especially,CcSte12 bound to the CcSp84 promoter region containing the TGA AAC A motif.Moreover,comparison of CcSte12-regulated genes with CcPmk1-regulated genes revealed 116 overlapping regulated genes in both CcSte12 and CcPmk1,including some virulence-associated genes.Taken together,the protein complexes CcSte11-CcSte7-CcPmk1 receive signals transmitted by upstream CcSte50 and transmit signals to downstream CcSte12,which regulates hydrolase,effectors and other genes to promote virulence.Overall,these results indicate that the CcPmk1-MAPK signaling pathway of C.chrysosperma plays a key role in the pathogenicity.
基金supported by the National Natural Science Foundation of China(Projects 31725004,U22A20458)the Key Realm Research and Development Program of Guangdong Province(Project 2020B0202090001)the Natural Science Foundation of Guangdong Province(Project 2023A1515012038).
文摘Calcium-dependent protein kinases(CDPKs/CPKs)are key regulators of plant stress signaling that translate calcium signals into cellular responses by phosphorylating diverse substrate proteins.However,the molecular mechanism by which plant cells relay calcium signals in response to hypoxia remains elusive.Here,we show that one member of the CDPK family in Arabidopsis thaliana,CPK12,is rapidly activated during hypoxia through calcium-dependent phosphorylation of its Ser-186 residue.Phosphorylated CPK12 shuttles from the cytoplasm to the nucleus,where it interacts with and phosphorylates the group Ⅶ ethylene-responsive transcription factors(ERF-Ⅶ)that are core regulators of plant hypoxia sensing,to enhance their stabilities.Consistently,CPK12 knockdown lines show attenuated tolerance of hypoxia,whereas transgenic plants overexpressing CPK12 display improved hypoxia tolerance.Nonethelss,loss of function of five ERF-Ⅶ proteins in an erf-vii pentuple mutant could partially suppress the enhanced hypoxia-tolerance phenotype of CPK12-overexpressing lines.Moreover,we also discovered that phosphatidic acid and 14-3-3κ protein serve as positive and negative modulators of the CPK12 cytoplasm-to-nucleus translocation,respectively.Taken together,these findings uncover a CPK12-ERF-Ⅶ regulatory module that is key to transducing calcium signals from the cytoplasm into the nucleus to potentiate hypoxia sensing in plants.
