Among APETALA2 (AP2)-type plant specific transcription factor family, WRINKLED1 (WRI1), has appeared to be a master gene transcriptionally regulating a set of carbon metabolism- and fatty acid synthesis (FAS)-related ...Among APETALA2 (AP2)-type plant specific transcription factor family, WRINKLED1 (WRI1), has appeared to be a master gene transcriptionally regulating a set of carbon metabolism- and fatty acid synthesis (FAS)-related genes responsible for seed specific triacylglycerols (TAGs) storage in oil plants. B3 type transcription factors, such as ABI3 and FUS3, are known to be involved in seed development, such as seed storage protein synthesis and maturation. Based on the recent whole genome sequence data of castor bean (Ricinus communis L.), putative WRI1 homologs (RcWRI1, RcWRI2) specifically expressed in castor bean seed have been identified by comparing organ specific expression profiles among seed development-related transcription factors, seed storage specific genes (Ricin, RcOleosin) and a set of FAS genes including genes for sucrose synthase (RcSUS2), biotin carboxyl carrier protein (a subunit of acetyl-CoA carboxylase, RcBCCP2) and ketoacyl-acyl carrier protein synthase (RcKAS1). Immunoreactive signals with WRI1, FUS3 and ABI5-related polypeptides were also detected in seed specifically, consistent with the expression profiles of seed development-related genes. The WRI1 binding consensus sites, [CnTnG](n)(7)[CG], designated as the AW-box, were found at the promoter region of RcBCCP2 and RcKAS1. Thus, RcWRI1 possibly play a pivotal role in seed specific TAGs storage during seed development by directly activating FAS -related genes.展开更多
To examine the expression profiles of oligodendrocyte transcription factors 1 and 2 （Oligl and Olig2） and the interaction between these two proteins, Oligl was transfected into the lateral ventricles of neonatal rat...To examine the expression profiles of oligodendrocyte transcription factors 1 and 2 （Oligl and Olig2） and the interaction between these two proteins, Oligl was transfected into the lateral ventricles of neonatal rats subjected to hypoxia. Immunohistochemistry demonstrated that Olig2 was expressed throughout the nuclei in the brain, and expression increased at 3 days following hypoxia and was higher than levels at 7 days following Ad5-Oligl transfection. Western blot revealed that Oligl and Olig2 expression increased in Oligl-transfected brain cells 3 days after hypoxia, but Oligl and Olig2 expression decreased at 7 days. These results indicate that Oligl overexpression enhances Olig2 expression in brain tissues of hypoxia rats.展开更多
BACKGROUND MicroRNA 34c(miR-34c)has been reported to be associated with malignant types of cancer,however,it remains unknown whether miR-34c is involved in chemoresistance in gastric cancer(GC).AIM To investigate the ...BACKGROUND MicroRNA 34c(miR-34c)has been reported to be associated with malignant types of cancer,however,it remains unknown whether miR-34c is involved in chemoresistance in gastric cancer(GC).AIM To investigate the effect of miR-34c and its upstream transcription factor E2F1 on paclitaxel combined with cisplatin resistance in GC cells.METHODS Paired GC tissues and adjacent normal tissues were randomly sampled from 74 GC patients.miR-34c and E2F1 were detected by real-time quantitative PCR(qPCR)and Western blot.In addition,the drug resistance of GC cells to paclitaxel and cisplatin was induced by concentration gradient increasing methods,and changes in miR-34c and E2F1 during this process were measured.Furthermore,E2F1 and miR-34c overexpression or underexpression vectors were constructed and transfected into drug-resistant GC cells.MTT was employed to test the sensitivity of cells to paclitaxel combined with cisplatin,qPCR was adopted to detect the expression of miR-34c,Western blot was applied to detect the expression levels of E2F1,drug resistance-related proteins and apoptosis-related proteins,and flow cytometry was used for the determination of cell apoptosis and cell cycle status.RESULTS E2F1 was overexpressed while miR-34c was underexpressed in GC.After inducing GC cells to be resistant to paclitaxel and cisplatin,E2F1 expression increased while miR-34c expression decreased.Both silencing E2F1 and overexpressing miR-34c could increase the sensitivity of drug-resistant GC cells to paclitaxel combined with cisplatin,promote cell apoptosis and inhibit cell proliferation.Among which,silencing E2F1 could reduce the expression of drug resistance-related proteins and apoptosis-related proteins,while over-expression of miR-34c could upregulate the expression of apoptosis-related proteins without affecting the expression of MDR-1,MRP and other drug resistance-related proteins.Rescue experiments demonstrated that inhibiting miR-34c could significantly weaken the sensitization of drug resistant cells,and Si E2F1 to paclitaxel combined with cisplatin.CONCLUSION E2F1 inhibits miR-34c to promote the proliferation of GC cells and enhance the resistance to paclitaxel combined with cisplatin,and silencing E2F1 is conducive to improving the efficacy of paclitaxel combined with cisplatin in GC cells.展开更多
BACKGROUND As a novel endogenous anti-angiogenic molecule, vasohibin 1(VASH1) is not only expressed in tumor stroma, but also in tumor tissue. Moreover, studies have shown that VASH1 may be a prognostic marker in colo...BACKGROUND As a novel endogenous anti-angiogenic molecule, vasohibin 1(VASH1) is not only expressed in tumor stroma, but also in tumor tissue. Moreover, studies have shown that VASH1 may be a prognostic marker in colorectal cancer(CRC). Knockdown of VASH1 enhanced transforming growth factor-β1(TGF-β1)/Smad3 pathway activity and type Ⅰ/Ⅲ collagen production. Our previous findings suggest that ELL-associated factor 2(EAF2) may play a tumor suppressor and protective role in the development and progression of CRC by regulating signal transducer and activator of transcription 3(STAT3)/TGF-β1 signaling pathway. However, the functional role and mechanism of VASH1-mediated TGF-β1 related pathway in CRC has not been elucidated.AIM To investigate the expression of VASH1 in CRC and its correlation with the expression of EAF2. Furthermore, we studied the functional role and mechanism of VASH1 involved in the regulation and protection of EAF2 in CRC cells in vitro.METHODS We collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein and VASH1 protein in patients with advanced CRC. Following, we investigated the effect and mechanism of EAF2 and VASH1 on the invasion, migration and angiogenesis of CRC cells in vitro using plasmid transfection.RESULTS Our findings indicated that EAF2 was down-regulated and VASH1 was upregulated in advanced CRC tissue compared to normal colorectal tissue. KaplanMeier survival analysis showed that the higher EAF2 Level group and the lower VASH1 Level group had a higher survival rate. Overexpression of EAF2 might inhibit the activity of STAT3/TGF-β1 pathway by up-regulating the expression of VASH1, and then weaken the invasion, migration and angiogenesis of CRC cells.CONCLUSION This study suggests that EAF2 and VASH1 may serve as new diagnostic and prognostic markers for CRC, and provide a clinical basis for exploring new biomarkers for CRC. This study complements the mechanism of EAF2 in CRC cells, enriches the role and mechanism of CRC cellderived VASH1, and provides a new possible subtype of CRC as a therapeutic target of STAT3/TGF-β1 pathway.展开更多
BACKGROUND A series of long non-coding RNAs(lncRNAs)have been reported to play a crucial role in cancer biology.Some previous studies report that lncRNA CDKN2B-AS1 is involved in some human malignancies.However,its ro...BACKGROUND A series of long non-coding RNAs(lncRNAs)have been reported to play a crucial role in cancer biology.Some previous studies report that lncRNA CDKN2B-AS1 is involved in some human malignancies.However,its role in hepatocellular carcinoma(HCC)has not been fully deciphered.AIM To decipher the role of CDKN2B-AS1 in the progression of HCC.METHODS CDKN2B-AS1 expression in HCC was detected by quantitative real-time polymerase chain reaction.The malignant phenotypes of Li-7 and SNU-182 cells were detected by the CCK-8 method,EdU method,and flow cytometry,respectively.RNA immunoprecipitation was executed to confirm the interaction between CDKN2B-AS1 and E2F transcription factor 1(E2F1).Luciferase reporter assay and chromatin immunoprecipitation were performed to verify the binding of E2F1 to the promoter of G protein subunit alpha Z(GNAZ).E2F1 and GNAZ were detected by western blot in HCC cells.RESULTS In HCC tissues,CDKN2B-AS1 was upregulated.Depletion of CDKN2B-AS1 inhibited the proliferation of HCC cells,and the depletion of CDKN2B-AS1 also induced cell cycle arrest and apoptosis.CDKN2B-AS1 could interact with E2F1.Depletion of CDKN2B-AS1 inhibited the binding of E2F1 to the GNAZ promoter region.Overexpression of E2F1 reversed the biological effects of depletion of CDKN2B-AS1 on the malignant behaviors of HCC cells.CONCLUSION CDKN2B-AS1 recruits E2F1 to facilitate GNAZ transcription to promote HCC progression.展开更多
An Amh promoter driving expression of a reporter gene (d2EGFP) has been used to analyze the role of two specific promoter transcription factor binding elements. In addition a downstream (3’) enhancer (DE) was also in...An Amh promoter driving expression of a reporter gene (d2EGFP) has been used to analyze the role of two specific promoter transcription factor binding elements. In addition a downstream (3’) enhancer (DE) was also investigated. The transcription factors GATA-1 and GATA-4 had opposite effects, the former being incremental and the latter decremental. The quantitative balance between these two factors may provide a degree of control over the level of gene expression.展开更多
BACKGROUND The androgen responsive gene,ELL-associated factor 2(EAF2),expressed in benign prostate tissues,has been shown to play an important role in tumor suppression in a variety of malignant tumors.In addition,som...BACKGROUND The androgen responsive gene,ELL-associated factor 2(EAF2),expressed in benign prostate tissues,has been shown to play an important role in tumor suppression in a variety of malignant tumors.In addition,some scholars found that EAF2 frameshift mutations are associated with intratumor heterogeneity in colorectal cancer(CRC)and inactivation of EAF2 in microsatellite instability-high CRC.However,the molecular mechanism by which EAF2 is involved in CRC invasion and metastasis remains unclear.AIM To determine the clinical value of expression of EAF2 protein in CRC,and to study the effects of EAF2 on the invasion,migration,and angiogenesis of CRC cells in vitro.METHODS In this study,we collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein in patients with advanced CRC.Subsequently,we investigated the effect of EAF2 on the invasion,migration,and angiogenesis of CRC cells in vitro using plasmid transfection.RESULTS EAF2 protein was lowly expressed in cancer tissues of patients with advanced CRC.Kaplan-Meier survival analysis showed that the survival rate of the high EAF2 level group was higher than that of the low EAF2 level group.CONCLUSION Our results demonstrated that EAF2,as a tumor suppressor,may inhibit the invasion,metastasis,and angiogenesis of CRC cells by regulating the signal transducer and activator of transcription 3/transforming growth factor-β1 crosstalk pathway,and play a cancer suppressive and protective role in the occurrence and development of CRC.Our findings are of great significance to provide a new idea and theoretical basis for the targeted diagnosis and treatment of CRC.展开更多
Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging...Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging immunotherapies.Here,we propose an alternative approach to treat GBM through reprogramming proliferative GBM cells into non-proliferative neurons.Methods:Retroviruses were used to target highly proliferative human GBM cells through overexpression of neural transcription factors.Immunostaining,electrophysiological recording,and bulk RNA-seq were performed to investigate the mechanisms underlying the neuronal conversion of human GBM cells.An in vivo intracranial xenograft mouse model was used to examine the neuronal conversion of human GBM cells.Results:We report efficient neuronal conversion from human GBM cells by overexpressing single neural transcription factor Neurogenic differentiation 1(Neuro D1),Neurogenin-2(Neurog2),or Achaete-scute homolog 1(Ascl1).Subtype characterization showed that the majority of Neurog2-and Neuro D1-converted neurons were glutamatergic,while Ascl1 favored GABAergic neuron generation.The GBM cell-converted neurons not only showed pan-neuronal markers but also exhibited neuron-specific electrophysiological activities.Transcriptome analyses revealed that neuronal genes were activated in glioma cells after overexpression of neural transcription factors,and different signaling pathways were activated by different neural transcription factors.Importantly,the neuronal conversion of GBM cells was accompanied by significant inhibition of GBM cell proliferation in both in vitro and in vivo models.Conclusions:These results suggest that GBM cells can be reprogrammed into different subtypes of neurons,leading to a potential alternative approach to treat brain tumors using in vivo cell conversion technology.展开更多
Many sources of stress cause accumulation of unfolded or misfolded proteins in endoplasmic reticulum(ER), which elicits the unfolded protein response(UPR) to either promote cell survival or programmed cell death depen...Many sources of stress cause accumulation of unfolded or misfolded proteins in endoplasmic reticulum(ER), which elicits the unfolded protein response(UPR) to either promote cell survival or programmed cell death depending on different developmental context or stress severity. The Arabidopsis membrane-associated transcription factor, b ZIP28, is the functional equivalent of mammalian ATF6, which relocates from the ER to the Golgi where it is proteolytically processed and released from the membrane to the nucleus to mediate the UPR. Although the canonical site-1 protease(S1P) cleavage site on the ER lumen-facing domain is well conserved between b ZIP28 and ATF6, the importance of S1 P cleavage on b ZIP28 has not been experimentally demonstrated. Here we provide genetic evidence that the RRIL573 site, but not the RVLM373 site, on the lumen-facing domain of bZ IP28 is critical for the biological function of b ZIP28 under ER stress condition. Further biochemistry and cell biology studies demonstrated that the RRIL573 site, but not the RVLM373 site, is required for proteolytic processing and nuclear relocation of b ZIP28 in response to ER stress. Our results reveal that S1 P cleavage site plays a pivotal role in activation and function of b ZIP28 during UPR in plants.展开更多
文摘Among APETALA2 (AP2)-type plant specific transcription factor family, WRINKLED1 (WRI1), has appeared to be a master gene transcriptionally regulating a set of carbon metabolism- and fatty acid synthesis (FAS)-related genes responsible for seed specific triacylglycerols (TAGs) storage in oil plants. B3 type transcription factors, such as ABI3 and FUS3, are known to be involved in seed development, such as seed storage protein synthesis and maturation. Based on the recent whole genome sequence data of castor bean (Ricinus communis L.), putative WRI1 homologs (RcWRI1, RcWRI2) specifically expressed in castor bean seed have been identified by comparing organ specific expression profiles among seed development-related transcription factors, seed storage specific genes (Ricin, RcOleosin) and a set of FAS genes including genes for sucrose synthase (RcSUS2), biotin carboxyl carrier protein (a subunit of acetyl-CoA carboxylase, RcBCCP2) and ketoacyl-acyl carrier protein synthase (RcKAS1). Immunoreactive signals with WRI1, FUS3 and ABI5-related polypeptides were also detected in seed specifically, consistent with the expression profiles of seed development-related genes. The WRI1 binding consensus sites, [CnTnG](n)(7)[CG], designated as the AW-box, were found at the promoter region of RcBCCP2 and RcKAS1. Thus, RcWRI1 possibly play a pivotal role in seed specific TAGs storage during seed development by directly activating FAS -related genes.
基金the National Natural Science Foundation of China, No. 30872778/C1704the Natural Science Foundation of Beijing, No. 7072023+1 种基金the Clinical Basic Cooperation Foundation of Capital Medical University, No. 2009jl18the Clinical Basic Cooperation Foundation of Capital Medical University, No.11JL-L03
文摘To examine the expression profiles of oligodendrocyte transcription factors 1 and 2 （Oligl and Olig2） and the interaction between these two proteins, Oligl was transfected into the lateral ventricles of neonatal rats subjected to hypoxia. Immunohistochemistry demonstrated that Olig2 was expressed throughout the nuclei in the brain, and expression increased at 3 days following hypoxia and was higher than levels at 7 days following Ad5-Oligl transfection. Western blot revealed that Oligl and Olig2 expression increased in Oligl-transfected brain cells 3 days after hypoxia, but Oligl and Olig2 expression decreased at 7 days. These results indicate that Oligl overexpression enhances Olig2 expression in brain tissues of hypoxia rats.
文摘BACKGROUND MicroRNA 34c(miR-34c)has been reported to be associated with malignant types of cancer,however,it remains unknown whether miR-34c is involved in chemoresistance in gastric cancer(GC).AIM To investigate the effect of miR-34c and its upstream transcription factor E2F1 on paclitaxel combined with cisplatin resistance in GC cells.METHODS Paired GC tissues and adjacent normal tissues were randomly sampled from 74 GC patients.miR-34c and E2F1 were detected by real-time quantitative PCR(qPCR)and Western blot.In addition,the drug resistance of GC cells to paclitaxel and cisplatin was induced by concentration gradient increasing methods,and changes in miR-34c and E2F1 during this process were measured.Furthermore,E2F1 and miR-34c overexpression or underexpression vectors were constructed and transfected into drug-resistant GC cells.MTT was employed to test the sensitivity of cells to paclitaxel combined with cisplatin,qPCR was adopted to detect the expression of miR-34c,Western blot was applied to detect the expression levels of E2F1,drug resistance-related proteins and apoptosis-related proteins,and flow cytometry was used for the determination of cell apoptosis and cell cycle status.RESULTS E2F1 was overexpressed while miR-34c was underexpressed in GC.After inducing GC cells to be resistant to paclitaxel and cisplatin,E2F1 expression increased while miR-34c expression decreased.Both silencing E2F1 and overexpressing miR-34c could increase the sensitivity of drug-resistant GC cells to paclitaxel combined with cisplatin,promote cell apoptosis and inhibit cell proliferation.Among which,silencing E2F1 could reduce the expression of drug resistance-related proteins and apoptosis-related proteins,while over-expression of miR-34c could upregulate the expression of apoptosis-related proteins without affecting the expression of MDR-1,MRP and other drug resistance-related proteins.Rescue experiments demonstrated that inhibiting miR-34c could significantly weaken the sensitization of drug resistant cells,and Si E2F1 to paclitaxel combined with cisplatin.CONCLUSION E2F1 inhibits miR-34c to promote the proliferation of GC cells and enhance the resistance to paclitaxel combined with cisplatin,and silencing E2F1 is conducive to improving the efficacy of paclitaxel combined with cisplatin in GC cells.
基金the Natural Science Foundation of Liaoning Province,No.2023-MS-149.
文摘BACKGROUND As a novel endogenous anti-angiogenic molecule, vasohibin 1(VASH1) is not only expressed in tumor stroma, but also in tumor tissue. Moreover, studies have shown that VASH1 may be a prognostic marker in colorectal cancer(CRC). Knockdown of VASH1 enhanced transforming growth factor-β1(TGF-β1)/Smad3 pathway activity and type Ⅰ/Ⅲ collagen production. Our previous findings suggest that ELL-associated factor 2(EAF2) may play a tumor suppressor and protective role in the development and progression of CRC by regulating signal transducer and activator of transcription 3(STAT3)/TGF-β1 signaling pathway. However, the functional role and mechanism of VASH1-mediated TGF-β1 related pathway in CRC has not been elucidated.AIM To investigate the expression of VASH1 in CRC and its correlation with the expression of EAF2. Furthermore, we studied the functional role and mechanism of VASH1 involved in the regulation and protection of EAF2 in CRC cells in vitro.METHODS We collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein and VASH1 protein in patients with advanced CRC. Following, we investigated the effect and mechanism of EAF2 and VASH1 on the invasion, migration and angiogenesis of CRC cells in vitro using plasmid transfection.RESULTS Our findings indicated that EAF2 was down-regulated and VASH1 was upregulated in advanced CRC tissue compared to normal colorectal tissue. KaplanMeier survival analysis showed that the higher EAF2 Level group and the lower VASH1 Level group had a higher survival rate. Overexpression of EAF2 might inhibit the activity of STAT3/TGF-β1 pathway by up-regulating the expression of VASH1, and then weaken the invasion, migration and angiogenesis of CRC cells.CONCLUSION This study suggests that EAF2 and VASH1 may serve as new diagnostic and prognostic markers for CRC, and provide a clinical basis for exploring new biomarkers for CRC. This study complements the mechanism of EAF2 in CRC cells, enriches the role and mechanism of CRC cellderived VASH1, and provides a new possible subtype of CRC as a therapeutic target of STAT3/TGF-β1 pathway.
文摘BACKGROUND A series of long non-coding RNAs(lncRNAs)have been reported to play a crucial role in cancer biology.Some previous studies report that lncRNA CDKN2B-AS1 is involved in some human malignancies.However,its role in hepatocellular carcinoma(HCC)has not been fully deciphered.AIM To decipher the role of CDKN2B-AS1 in the progression of HCC.METHODS CDKN2B-AS1 expression in HCC was detected by quantitative real-time polymerase chain reaction.The malignant phenotypes of Li-7 and SNU-182 cells were detected by the CCK-8 method,EdU method,and flow cytometry,respectively.RNA immunoprecipitation was executed to confirm the interaction between CDKN2B-AS1 and E2F transcription factor 1(E2F1).Luciferase reporter assay and chromatin immunoprecipitation were performed to verify the binding of E2F1 to the promoter of G protein subunit alpha Z(GNAZ).E2F1 and GNAZ were detected by western blot in HCC cells.RESULTS In HCC tissues,CDKN2B-AS1 was upregulated.Depletion of CDKN2B-AS1 inhibited the proliferation of HCC cells,and the depletion of CDKN2B-AS1 also induced cell cycle arrest and apoptosis.CDKN2B-AS1 could interact with E2F1.Depletion of CDKN2B-AS1 inhibited the binding of E2F1 to the GNAZ promoter region.Overexpression of E2F1 reversed the biological effects of depletion of CDKN2B-AS1 on the malignant behaviors of HCC cells.CONCLUSION CDKN2B-AS1 recruits E2F1 to facilitate GNAZ transcription to promote HCC progression.
文摘An Amh promoter driving expression of a reporter gene (d2EGFP) has been used to analyze the role of two specific promoter transcription factor binding elements. In addition a downstream (3’) enhancer (DE) was also investigated. The transcription factors GATA-1 and GATA-4 had opposite effects, the former being incremental and the latter decremental. The quantitative balance between these two factors may provide a degree of control over the level of gene expression.
基金Supported by the Natural Science Foundation of Liaoning Province,No.2019-BS-279.
文摘BACKGROUND The androgen responsive gene,ELL-associated factor 2(EAF2),expressed in benign prostate tissues,has been shown to play an important role in tumor suppression in a variety of malignant tumors.In addition,some scholars found that EAF2 frameshift mutations are associated with intratumor heterogeneity in colorectal cancer(CRC)and inactivation of EAF2 in microsatellite instability-high CRC.However,the molecular mechanism by which EAF2 is involved in CRC invasion and metastasis remains unclear.AIM To determine the clinical value of expression of EAF2 protein in CRC,and to study the effects of EAF2 on the invasion,migration,and angiogenesis of CRC cells in vitro.METHODS In this study,we collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein in patients with advanced CRC.Subsequently,we investigated the effect of EAF2 on the invasion,migration,and angiogenesis of CRC cells in vitro using plasmid transfection.RESULTS EAF2 protein was lowly expressed in cancer tissues of patients with advanced CRC.Kaplan-Meier survival analysis showed that the survival rate of the high EAF2 level group was higher than that of the low EAF2 level group.CONCLUSION Our results demonstrated that EAF2,as a tumor suppressor,may inhibit the invasion,metastasis,and angiogenesis of CRC cells by regulating the signal transducer and activator of transcription 3/transforming growth factor-β1 crosstalk pathway,and play a cancer suppressive and protective role in the occurrence and development of CRC.Our findings are of great significance to provide a new idea and theoretical basis for the targeted diagnosis and treatment of CRC.
基金supported by the Charles H.“Skip”Smith Endowment Fund and the Verne M.Willaman Endowment Fund from the Pennsylvania State University to G.C。
文摘Objective:Glioblastoma(GBM)is the most prevalent and aggressive adult primary cancer in the central nervous system.Therapeutic approaches for GBM treatment are under intense investigation,including the use of emerging immunotherapies.Here,we propose an alternative approach to treat GBM through reprogramming proliferative GBM cells into non-proliferative neurons.Methods:Retroviruses were used to target highly proliferative human GBM cells through overexpression of neural transcription factors.Immunostaining,electrophysiological recording,and bulk RNA-seq were performed to investigate the mechanisms underlying the neuronal conversion of human GBM cells.An in vivo intracranial xenograft mouse model was used to examine the neuronal conversion of human GBM cells.Results:We report efficient neuronal conversion from human GBM cells by overexpressing single neural transcription factor Neurogenic differentiation 1(Neuro D1),Neurogenin-2(Neurog2),or Achaete-scute homolog 1(Ascl1).Subtype characterization showed that the majority of Neurog2-and Neuro D1-converted neurons were glutamatergic,while Ascl1 favored GABAergic neuron generation.The GBM cell-converted neurons not only showed pan-neuronal markers but also exhibited neuron-specific electrophysiological activities.Transcriptome analyses revealed that neuronal genes were activated in glioma cells after overexpression of neural transcription factors,and different signaling pathways were activated by different neural transcription factors.Importantly,the neuronal conversion of GBM cells was accompanied by significant inhibition of GBM cell proliferation in both in vitro and in vivo models.Conclusions:These results suggest that GBM cells can be reprogrammed into different subtypes of neurons,leading to a potential alternative approach to treat brain tumors using in vivo cell conversion technology.
基金supported by grants from the National Basic Research Program of China(973 Program,2012CB910500)the National Natural Science Foundation of China(31171157,31222008)the Specialized Research Fund for the Doctoral Program of Higher Education(20130071110011)
文摘Many sources of stress cause accumulation of unfolded or misfolded proteins in endoplasmic reticulum(ER), which elicits the unfolded protein response(UPR) to either promote cell survival or programmed cell death depending on different developmental context or stress severity. The Arabidopsis membrane-associated transcription factor, b ZIP28, is the functional equivalent of mammalian ATF6, which relocates from the ER to the Golgi where it is proteolytically processed and released from the membrane to the nucleus to mediate the UPR. Although the canonical site-1 protease(S1P) cleavage site on the ER lumen-facing domain is well conserved between b ZIP28 and ATF6, the importance of S1 P cleavage on b ZIP28 has not been experimentally demonstrated. Here we provide genetic evidence that the RRIL573 site, but not the RVLM373 site, on the lumen-facing domain of bZ IP28 is critical for the biological function of b ZIP28 under ER stress condition. Further biochemistry and cell biology studies demonstrated that the RRIL573 site, but not the RVLM373 site, is required for proteolytic processing and nuclear relocation of b ZIP28 in response to ER stress. Our results reveal that S1 P cleavage site plays a pivotal role in activation and function of b ZIP28 during UPR in plants.
