CSN1 is a component of the COP9 signalosome(CSN),a conserved protein complex with pleiotropic functions in many organs and cell types.CSN regulates ubiquitinproteasome dependent protein degradation via the deneddylati...CSN1 is a component of the COP9 signalosome(CSN),a conserved protein complex with pleiotropic functions in many organs and cell types.CSN regulates ubiquitinproteasome dependent protein degradation via the deneddylation and the associated deubiquitination activities.In addition,CSN associates with protein kinases and modulates cell signaling,particularly the activator protein 1(AP-1)pathway.We have shown previously that CSN1 suppresses AP-1 transcription activity and inhibits ultraviolet(UV)and serum activation of c-fos expression.Here we show that CSN1 can inhibit phosphorylation of proto-oncogene c-Jun product and repress c-Jun dependent transcription.Further,CSN1 dramatically downregulates ectopic expression of c-Jun N-terminal kinase 1(JNK1)in cultured cells.The decline in JNK1 is not caused by excessive proteolysis or by 3′UTR-dependent mRNA instability,but by CSN1-dependent repression of one or multiple steps in transcriptional and posttranscriptional mechanisms.Thus,in contrast to CSN5/Jab1,which promotes AP-1 activity,CSN1 displays a negative effect on the AP-1 pathway.Finally,we discuss about the dynamic equilibrium of the CSN complexes in regulation of the AP-1 pathway.展开更多
目的探讨香烟烟雾对哮喘大鼠肺组织内皮素2(ET-2)表达的影响。方法大鼠腹腔注射鸡卵清蛋白/Al(OH)3混合液1 m L致敏建立哮喘模型(哮喘模型组,n=6),在哮喘模型组基础上烟熏(10支/d)连续4周为香烟烟雾哮喘组(烟雾哮喘组,n=6),分别以地塞米...目的探讨香烟烟雾对哮喘大鼠肺组织内皮素2(ET-2)表达的影响。方法大鼠腹腔注射鸡卵清蛋白/Al(OH)3混合液1 m L致敏建立哮喘模型(哮喘模型组,n=6),在哮喘模型组基础上烟熏(10支/d)连续4周为香烟烟雾哮喘组(烟雾哮喘组,n=6),分别以地塞米松2 mg/(kg·d)腹腔注射1周、ET受体抑制剂波生坦100 mg/(kg·d)灌胃及联合处理分为地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组,每组6只,设正常对照(正常对照组,腹腔注射生理盐水1 m L,n=6)及香烟烟雾对照[在正常对照组基础上,连续烟熏(10支/d)4周,n=6]。收集左肺上叶支气管肺泡灌洗液(BALF)检测细胞计数及分类,右肺上叶HE染色观察肺组织病理学改变;其余肺组织行Western blot法及免疫组织化学染色法分别检测肺组织c-Jun氨基末端激酶1/2(JNK1/2)、ET-2蛋白水平,硫代巴比妥酸法测丙二醛(MDA)水平,微量酶标法测谷胱甘肽(GSH)水平。结果与对照组比较,香烟烟雾对照组、哮喘模型组、香烟烟雾哮喘组BALF中白细胞数、中性粒细胞数及嗜酸性粒细胞数升高,肺组织中ET-2蛋白、JNK1/2蛋白、MDA及GSH水平升高;而与香烟烟雾哮喘组比较,地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组BALF中白细胞数、中性粒细胞数及嗜酸性粒细胞数均降低。肺组织中ET-2蛋白、JNK1/2蛋白、MDA及GSH表达降低。地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组气道炎症均有改善,地塞米松及波生坦处理组改善最明显。ET-2在地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组肺组织染色强度减少,地塞米松及波生坦处理组染色强度减少更明显。结论香烟烟雾暴露可加重哮喘大鼠气道炎症,ET受体抑制剂波生坦可改善气道炎症,香烟烟雾暴露哮喘发生的炎症机制可能与ET-2及JNK1/2通路有关。展开更多
基金supported by research grants from the National Institutes of Health(GM61812)to NWthe Human Frontier Long Term Fellowship(LT0084/1998-M)to TTa collaborative grant from The Kyoto University Foundation(2007-2008)to NW,SM,and TT.
文摘CSN1 is a component of the COP9 signalosome(CSN),a conserved protein complex with pleiotropic functions in many organs and cell types.CSN regulates ubiquitinproteasome dependent protein degradation via the deneddylation and the associated deubiquitination activities.In addition,CSN associates with protein kinases and modulates cell signaling,particularly the activator protein 1(AP-1)pathway.We have shown previously that CSN1 suppresses AP-1 transcription activity and inhibits ultraviolet(UV)and serum activation of c-fos expression.Here we show that CSN1 can inhibit phosphorylation of proto-oncogene c-Jun product and repress c-Jun dependent transcription.Further,CSN1 dramatically downregulates ectopic expression of c-Jun N-terminal kinase 1(JNK1)in cultured cells.The decline in JNK1 is not caused by excessive proteolysis or by 3′UTR-dependent mRNA instability,but by CSN1-dependent repression of one or multiple steps in transcriptional and posttranscriptional mechanisms.Thus,in contrast to CSN5/Jab1,which promotes AP-1 activity,CSN1 displays a negative effect on the AP-1 pathway.Finally,we discuss about the dynamic equilibrium of the CSN complexes in regulation of the AP-1 pathway.
文摘目的探讨香烟烟雾对哮喘大鼠肺组织内皮素2(ET-2)表达的影响。方法大鼠腹腔注射鸡卵清蛋白/Al(OH)3混合液1 m L致敏建立哮喘模型(哮喘模型组,n=6),在哮喘模型组基础上烟熏(10支/d)连续4周为香烟烟雾哮喘组(烟雾哮喘组,n=6),分别以地塞米松2 mg/(kg·d)腹腔注射1周、ET受体抑制剂波生坦100 mg/(kg·d)灌胃及联合处理分为地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组,每组6只,设正常对照(正常对照组,腹腔注射生理盐水1 m L,n=6)及香烟烟雾对照[在正常对照组基础上,连续烟熏(10支/d)4周,n=6]。收集左肺上叶支气管肺泡灌洗液(BALF)检测细胞计数及分类,右肺上叶HE染色观察肺组织病理学改变;其余肺组织行Western blot法及免疫组织化学染色法分别检测肺组织c-Jun氨基末端激酶1/2(JNK1/2)、ET-2蛋白水平,硫代巴比妥酸法测丙二醛(MDA)水平,微量酶标法测谷胱甘肽(GSH)水平。结果与对照组比较,香烟烟雾对照组、哮喘模型组、香烟烟雾哮喘组BALF中白细胞数、中性粒细胞数及嗜酸性粒细胞数升高,肺组织中ET-2蛋白、JNK1/2蛋白、MDA及GSH水平升高;而与香烟烟雾哮喘组比较,地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组BALF中白细胞数、中性粒细胞数及嗜酸性粒细胞数均降低。肺组织中ET-2蛋白、JNK1/2蛋白、MDA及GSH表达降低。地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组气道炎症均有改善,地塞米松及波生坦处理组改善最明显。ET-2在地塞米松处理组、波生坦处理组、地塞米松及波生坦处理组肺组织染色强度减少,地塞米松及波生坦处理组染色强度减少更明显。结论香烟烟雾暴露可加重哮喘大鼠气道炎症,ET受体抑制剂波生坦可改善气道炎症,香烟烟雾暴露哮喘发生的炎症机制可能与ET-2及JNK1/2通路有关。
