目的研究固醇调节元件结合蛋白1c(sterol regulatory element binding protein 1c,SREBP1c)对肠道糖异生的调控作用。方法饥饿处理C57BL/6小鼠、SREBP1c纯合敲除型(SREBP1c-KO)和同窝野生型(SREBP1c-WT)小鼠,通过qPCR、Western blot检...目的研究固醇调节元件结合蛋白1c(sterol regulatory element binding protein 1c,SREBP1c)对肠道糖异生的调控作用。方法饥饿处理C57BL/6小鼠、SREBP1c纯合敲除型(SREBP1c-KO)和同窝野生型(SREBP1c-WT)小鼠,通过qPCR、Western blot检测糖异生途径限速酶葡萄糖-6-磷酸酶(glucose-6-phosphatase catalytic,G6PC)和磷酸烯醇式丙酮酸羧激酶(phosphoenolpyruvate carboxykinase 1,PCK1)在肝脏、空肠和回肠组织中的表达水平;在肠上皮细胞CaCo-2中过表达或敲低SREBP1c,检测细胞内G6PC和PCK1表达水平。结果饥饿处理后,C57BL/6小鼠空肠、回肠组织中G6PC、PCK1和SREBP1c表达水平均显著增加(P<0.05)。SREBP1c基因敲除后,小鼠空肠、回肠组织中由饥饿诱导的糖异生限速酶G6PC和PCK1的表达明显下调(P<0.05)。在肠上皮细胞CaCo-2中过表达SREBP1c,可显著上调糖异生途径关键酶G6PC和PCK1的表达,促进细胞内葡萄糖的产生(P<0.05);反之,敲低SREBP1c的表达,可明显下调G6PC和PCK1,抑制细胞内葡萄糖的产生(P<0.05)。结论饥饿状态下,SREBP1c可调控肠上皮细胞中糖异生限速酶G6PC和PCK1的表达,进而影响葡萄糖的生成,表明SREBP1c可能参与肠道糖异生的调控,机制有待进一步探索。展开更多
目的筛选影响胆固醇调节元件结合蛋白1a(cholesterol regulatory element binding protein,SREBP1a)蛋白稳定性的去泛素化酶,并探索其调控机制。方法通过去泛素化酶库筛选显著影响SREBP1a表达的去泛素化酶,免疫蛋白印记实验和实时荧光定...目的筛选影响胆固醇调节元件结合蛋白1a(cholesterol regulatory element binding protein,SREBP1a)蛋白稳定性的去泛素化酶,并探索其调控机制。方法通过去泛素化酶库筛选显著影响SREBP1a表达的去泛素化酶,免疫蛋白印记实验和实时荧光定量PCR(qRT-PCR)评估去泛素化酶对SREBP1a以及升脂基因表达的影响;通过红色荧光蛋白标记人源低密度脂蛋白(human Dil-low density lipoprotein,Human Dil-LDL)摄取和油红O染色等实验技术检测细胞摄取低密度脂蛋白(LDL)和脂质沉积情况。结果去泛素化酶库筛选发现泛素特异肽酶37(ubiquitin specific peptidase 37,USP37)可显著增加肝细胞SREBP1a蛋白表达水平,促进胆固醇摄取及脂质沉积。USP37基因敲除可显著降低SREBP1a蛋白表达水平,抑制升脂基因表达及脂质沉积。结论去泛素化酶USP37通过稳定SREBP1a蛋白表达,促进胆固醇摄取及脂质沉积,揭示了SREBP1a翻译后调控的新模式。展开更多
Objective:To investigate the relationship between SREBP1 protein expression and clinicopathological features of hepatitis B virus infection-related hepatocellular carcinoma.Methods:A total of 91 cases of hepatocellula...Objective:To investigate the relationship between SREBP1 protein expression and clinicopathological features of hepatitis B virus infection-related hepatocellular carcinoma.Methods:A total of 91 cases of hepatocellular carcinoma associated with hepatitis B virus infection and paired adjacent liver tissue samples were collected from the Department of Pathology,the First Affiliated Hospital of Hainan Medical College.The expression of SREBP1 protein in cancer and paired adjacent tissues was detected by immunohistochemical staining.The relationship between SREBP1 protein expression and clinicopathological features of hepatocellular carcinoma was analyzed by chi-square test.Results:The results of immunohistochemical staining showed that the ex-pression of SREBP1 protein in hepatocellular carcinoma was significantly higher than that in adjacent liver tissues(P<0.001).The expression level of SREBP1 protein was significantly correlated with tumor differentiation,distant metastasis or local recurrence in patients with hepatocellular carcinoma(P<0.05).The expression of SREBP1 protein was significantly up-regulated in the high HBV-related HCC virus load group(>103 IU/mL)compared with the low HBV-related HCC virus load group 3(0~10 IU/mL)(P<0.05).Conclusion:1.The expression of SREBP1 protein is correlated with hepatocellular carcinoma,and shows a high expression trend,which provides direction and theoretical basis for the study of lipid metabolism regulation mechnism related to the occurrence and development of hepatocellular carcinoma.2.The expression of SREBP1 protein is correlated with the replication activity of hepatitis B virus,which provides a new research direction for the exploration of the mechanism of the occurrence and development of hepatitis B virus infection-related liver cancer.展开更多
甾醇调节原件结合蛋白1(sterol regulatory element binding protein 1,SREBP1)是脂质合成代谢中的关键蛋白,能够促进细胞中脂质合成基因的转录,进而促进脂质合成,在能量供应及储存、细胞膜与细胞器膜的构建等方面发挥重要作用。脂质代...甾醇调节原件结合蛋白1(sterol regulatory element binding protein 1,SREBP1)是脂质合成代谢中的关键蛋白,能够促进细胞中脂质合成基因的转录,进而促进脂质合成,在能量供应及储存、细胞膜与细胞器膜的构建等方面发挥重要作用。脂质代谢异常与肿瘤的发生密切相关,近年来研究发现,SREBP1在肿瘤中异常高表达,与肿瘤的发生发展密切相关。本文主要对SREBP1的结构、功能,及其在肿瘤发生发展中的作用及机制进行综述,为肿瘤的基础研究及临床治疗提供新的思路和潜在的治疗靶点。展开更多
固醇调控元件结合蛋白1(Sterol regulatory element-binding protein 1,SREBP1)通过调控脂肪生成相关的酶基因的转录,在机体脂类代谢调控中起着重要作用.本研究以21日龄的鸡胚肝组织的cDNA为模板,通过PCR分段克隆Srebp1全长基因的编码...固醇调控元件结合蛋白1(Sterol regulatory element-binding protein 1,SREBP1)通过调控脂肪生成相关的酶基因的转录,在机体脂类代谢调控中起着重要作用.本研究以21日龄的鸡胚肝组织的cDNA为模板,通过PCR分段克隆Srebp1全长基因的编码区片段,采用生物信息学分析其蛋白质功能结构域,将SREBP1功能结构域的编码片段克隆入原核表达载体pColdⅢ中,在大肠杆菌BL21(DE3)进行该功能片段的诱导表达.结果表明利用该基因内的KpnⅠ和NotⅠ两个限制性酶切位点,成功将鸡Srebp1基因上分别长700,1300,1500 bp 3个片段依次插入pcDNA3.1(+)质粒的HindⅢ和XhoⅠ酶切位点之间,获得全长Srebp1基因编码片段;在15℃和异丙基硫代半乳糖苷(Isopropylβ-D-Thiogalactoside,IPTG)的诱导条件下,pColdⅢ-g Srebp1-1125重组表达质粒在大肠杆菌BL21(DE3)中成功表达出重组蛋白gSREBP1-1125;SDS-PAGE电泳结果显示,重组蛋白gSREBP1-1125部分呈可溶性表达,但主要以包涵体存在.镍离子一步亲和层析法从菌体的裂解上清中获得了高纯度的重组蛋白;结合镍离子亲和层析,对重组蛋白进行固-液两相法复性,成功从包涵体中纯化得到高纯度的可溶性gSREBP1-1125功能多肽.鸡Srebp1真核表达载体和功能片段重组蛋白的获得为进一步研究其结构、功能以及抗体的制备奠定了基础.展开更多
文摘目的研究固醇调节元件结合蛋白1c(sterol regulatory element binding protein 1c,SREBP1c)对肠道糖异生的调控作用。方法饥饿处理C57BL/6小鼠、SREBP1c纯合敲除型(SREBP1c-KO)和同窝野生型(SREBP1c-WT)小鼠,通过qPCR、Western blot检测糖异生途径限速酶葡萄糖-6-磷酸酶(glucose-6-phosphatase catalytic,G6PC)和磷酸烯醇式丙酮酸羧激酶(phosphoenolpyruvate carboxykinase 1,PCK1)在肝脏、空肠和回肠组织中的表达水平;在肠上皮细胞CaCo-2中过表达或敲低SREBP1c,检测细胞内G6PC和PCK1表达水平。结果饥饿处理后,C57BL/6小鼠空肠、回肠组织中G6PC、PCK1和SREBP1c表达水平均显著增加(P<0.05)。SREBP1c基因敲除后,小鼠空肠、回肠组织中由饥饿诱导的糖异生限速酶G6PC和PCK1的表达明显下调(P<0.05)。在肠上皮细胞CaCo-2中过表达SREBP1c,可显著上调糖异生途径关键酶G6PC和PCK1的表达,促进细胞内葡萄糖的产生(P<0.05);反之,敲低SREBP1c的表达,可明显下调G6PC和PCK1,抑制细胞内葡萄糖的产生(P<0.05)。结论饥饿状态下,SREBP1c可调控肠上皮细胞中糖异生限速酶G6PC和PCK1的表达,进而影响葡萄糖的生成,表明SREBP1c可能参与肠道糖异生的调控,机制有待进一步探索。
文摘目的筛选影响胆固醇调节元件结合蛋白1a(cholesterol regulatory element binding protein,SREBP1a)蛋白稳定性的去泛素化酶,并探索其调控机制。方法通过去泛素化酶库筛选显著影响SREBP1a表达的去泛素化酶,免疫蛋白印记实验和实时荧光定量PCR(qRT-PCR)评估去泛素化酶对SREBP1a以及升脂基因表达的影响;通过红色荧光蛋白标记人源低密度脂蛋白(human Dil-low density lipoprotein,Human Dil-LDL)摄取和油红O染色等实验技术检测细胞摄取低密度脂蛋白(LDL)和脂质沉积情况。结果去泛素化酶库筛选发现泛素特异肽酶37(ubiquitin specific peptidase 37,USP37)可显著增加肝细胞SREBP1a蛋白表达水平,促进胆固醇摄取及脂质沉积。USP37基因敲除可显著降低SREBP1a蛋白表达水平,抑制升脂基因表达及脂质沉积。结论去泛素化酶USP37通过稳定SREBP1a蛋白表达,促进胆固醇摄取及脂质沉积,揭示了SREBP1a翻译后调控的新模式。
基金Natural Science Foundation of Hainan Province(No.820RC763)。
文摘Objective:To investigate the relationship between SREBP1 protein expression and clinicopathological features of hepatitis B virus infection-related hepatocellular carcinoma.Methods:A total of 91 cases of hepatocellular carcinoma associated with hepatitis B virus infection and paired adjacent liver tissue samples were collected from the Department of Pathology,the First Affiliated Hospital of Hainan Medical College.The expression of SREBP1 protein in cancer and paired adjacent tissues was detected by immunohistochemical staining.The relationship between SREBP1 protein expression and clinicopathological features of hepatocellular carcinoma was analyzed by chi-square test.Results:The results of immunohistochemical staining showed that the ex-pression of SREBP1 protein in hepatocellular carcinoma was significantly higher than that in adjacent liver tissues(P<0.001).The expression level of SREBP1 protein was significantly correlated with tumor differentiation,distant metastasis or local recurrence in patients with hepatocellular carcinoma(P<0.05).The expression of SREBP1 protein was significantly up-regulated in the high HBV-related HCC virus load group(>103 IU/mL)compared with the low HBV-related HCC virus load group 3(0~10 IU/mL)(P<0.05).Conclusion:1.The expression of SREBP1 protein is correlated with hepatocellular carcinoma,and shows a high expression trend,which provides direction and theoretical basis for the study of lipid metabolism regulation mechnism related to the occurrence and development of hepatocellular carcinoma.2.The expression of SREBP1 protein is correlated with the replication activity of hepatitis B virus,which provides a new research direction for the exploration of the mechanism of the occurrence and development of hepatitis B virus infection-related liver cancer.
文摘甾醇调节原件结合蛋白1(sterol regulatory element binding protein 1,SREBP1)是脂质合成代谢中的关键蛋白,能够促进细胞中脂质合成基因的转录,进而促进脂质合成,在能量供应及储存、细胞膜与细胞器膜的构建等方面发挥重要作用。脂质代谢异常与肿瘤的发生密切相关,近年来研究发现,SREBP1在肿瘤中异常高表达,与肿瘤的发生发展密切相关。本文主要对SREBP1的结构、功能,及其在肿瘤发生发展中的作用及机制进行综述,为肿瘤的基础研究及临床治疗提供新的思路和潜在的治疗靶点。
文摘固醇调控元件结合蛋白1(Sterol regulatory element-binding protein 1,SREBP1)通过调控脂肪生成相关的酶基因的转录,在机体脂类代谢调控中起着重要作用.本研究以21日龄的鸡胚肝组织的cDNA为模板,通过PCR分段克隆Srebp1全长基因的编码区片段,采用生物信息学分析其蛋白质功能结构域,将SREBP1功能结构域的编码片段克隆入原核表达载体pColdⅢ中,在大肠杆菌BL21(DE3)进行该功能片段的诱导表达.结果表明利用该基因内的KpnⅠ和NotⅠ两个限制性酶切位点,成功将鸡Srebp1基因上分别长700,1300,1500 bp 3个片段依次插入pcDNA3.1(+)质粒的HindⅢ和XhoⅠ酶切位点之间,获得全长Srebp1基因编码片段;在15℃和异丙基硫代半乳糖苷(Isopropylβ-D-Thiogalactoside,IPTG)的诱导条件下,pColdⅢ-g Srebp1-1125重组表达质粒在大肠杆菌BL21(DE3)中成功表达出重组蛋白gSREBP1-1125;SDS-PAGE电泳结果显示,重组蛋白gSREBP1-1125部分呈可溶性表达,但主要以包涵体存在.镍离子一步亲和层析法从菌体的裂解上清中获得了高纯度的重组蛋白;结合镍离子亲和层析,对重组蛋白进行固-液两相法复性,成功从包涵体中纯化得到高纯度的可溶性gSREBP1-1125功能多肽.鸡Srebp1真核表达载体和功能片段重组蛋白的获得为进一步研究其结构、功能以及抗体的制备奠定了基础.