Alzheimer's disease(AD)is characterized by complex etiology,long-lasting pathogenesis,and celltype-specific alterations.Currently,there is no cure for AD,emphasizing the urgent need for a comprehensive understandi...Alzheimer's disease(AD)is characterized by complex etiology,long-lasting pathogenesis,and celltype-specific alterations.Currently,there is no cure for AD,emphasizing the urgent need for a comprehensive understanding of cell-specific pathology.Astrocytes,principal homeostatic cells of the central nervous system,are key players in the pathogenesis of neurodegenerative diseases,including AD.Cellular models greatly facilitate the investigation of cell-specific pathological alterations and the dissection of molecular mechanisms and pathways.Tumor-derived and immortalized astrocytic cell lines,alongside the emerging technology of adult induced pluripotent stem cells,are widely used to study cellular dysfunction in AD.Surprisingly,no stable cell lines were available from genetic mouse AD models.Recently,we established immortalized hippocampal astroglial cell lines from amyloid-βprecursor protein/presenilin-1/Tau triple-transgenic(3xTg)-AD mice(denominated as wild type(WT)-and 3Tg-iAstro cells)using retrovirus-mediated transduction of simian virus 40 large T-antigen and propagation without clonal selection,thereby maintaining natural heterogeneity of primary cultures.Several groups have successfully used 3Tg-iAstro cells for single-cell and omics approaches to study astrocytic AD-related alterations of calcium signaling,mitochondrial dysfunctions,disproteostasis,altered homeostatic and signaling support to neurons,and blood-brain barrier models.Here we provide a comparative overview of the most used models to study astrocytes in vitro,such as primary culture,tumor-derived cell lines,immortalized astroglial cell lines,and induced pluripotent stem cell-derived astrocytes.We conclude that immortalized WT-and 3Tg-iAstro cells provide a noncompetitive but complementary,low-cost,easy-to-handle,and versatile cellular model for dissection of astrocyte-specific AD-related alterations and preclinical drug discovery.展开更多
真核生物细胞中,双层膜细胞器线粒体会进行持续的分裂与融合,从而改变自身形态来满足细胞在不同生长条件下的能量代谢需求.除此之外,线粒体的动态与功能还依赖于与其他细胞器的互作及一些代谢产物在互作过程中的双向交流.与线粒体互作...真核生物细胞中,双层膜细胞器线粒体会进行持续的分裂与融合,从而改变自身形态来满足细胞在不同生长条件下的能量代谢需求.除此之外,线粒体的动态与功能还依赖于与其他细胞器的互作及一些代谢产物在互作过程中的双向交流.与线粒体互作的细胞器包括脂滴、过氧化物酶体、液泡和内质网等.在真菌细胞中,线粒体与内质网的互作由存在二者之间的内质网-线粒体接触复合物(ER and mitochondria encounter structure,ERMES)介导.ERMES复合物对于维持线粒体的形态和功能至关重要,其破坏会影响线粒体的动态、钙离子信号、磷脂组分的转运、真菌耐药性和致病真菌的毒力等.本文着重对ERMES复合物在真菌细胞中的组装、功能及其组装调控机制进行系统的总结和讨论.展开更多
文摘【背景】随着规模化、集约化生产程度的不断提高,养殖过程中饲养空间受限、冷热环境不适等因素常使猪处于应激状态。内质网应激(endoplasmic reticulum stress,ERS)可能是最早期的应激反应,与细胞凋亡、代谢等方面有密切联系。肝脏是机体的主要代谢器官,猪养殖过程中由于人工操作(如断奶)、饲料霉变、温度变化和吸入有害气体等因素都会造成猪肝脏的ERS,不仅会造成肝脏损伤,还会引发肝脏的脂肪代谢紊乱和广泛的炎症反应,影响生产性能和繁殖性能。因此,深入探讨缓解ERS的有效措施,有助于减少猪养殖过程中的隐性损失。【目的】利用免疫沉淀联合质谱技术,从猪肝星状细胞中筛选在ERS条件下与葡萄糖调节蛋白94(GRP94)相互作用的细胞蛋白,为进一步探讨GRP94对猪肝星状细胞生物学功能的保护作用机理奠定基础。【方法】首先将GRP94抗体固定在谷胱甘肽亲和磁珠上,用亲和磁珠与ERS条件下或正常条件下猪肝星状细胞总蛋白进行孵育,与GRP94诱饵蛋白结合的蛋白复合物洗脱收集后,进行SDS-PAGE凝胶电泳验证。将验证成功的样品洗脱液进行液相色谱串联质谱(LC-MS/MS)检测,鉴定出正常条件和ERS条件下GRP94的互作蛋白。运用生物信息学在线软件对筛选的互作细胞蛋白进行GO富集、KEGG信号通路注释和蛋白互作网络分析,并对其中的互作蛋白之一波形蛋白(vimentin)进行免疫共沉淀验证。【结果】筛选到正常条件下与GRP94存在互作关系的蛋白146个,ERS条件下与GRP94存在互作关系的蛋白76个,在两种情况下都存在互作关系的蛋白44个。ERS条件下有互作关系的76个蛋白质主要参与凋亡过程负调控、肽段交联、泛素依赖型ERAD(endoplasmic reticulum associated degradation)过程和过氧化氢分解代谢等过程。其中参与凋亡过程负调控的GRP94互作蛋白有albumin、catalase、filament A、heat shock protein family A member 5、keratin 18和prohibin 2,说明GRP94可能与这些蛋白共同发挥抗凋亡作用。除此之外组成中间丝纤维的vimentin蛋白参与多个GO富集的通路,可能与GRP94有重要的互作关系。进一步的免疫共沉淀试验也证实,ERS条件下vimentin和GRP94之间确实存在互作关系。此外,某些ERS条件下特异性表达的GRP94互作蛋白(如peroxiredoxin、death inducer obliterator 1、catalase、glandular kallikrein、pyruvate kinase等)与抗凋亡有密切联系。【结论】ERS条件下,猪肝脏GRP94互作蛋白主要参与抗凋亡、对未折叠蛋白进行折叠和维护细胞内稳态相关的信号通路。该结论为下一步开展GRP94参与肝脏ERS调控机制的研究打下基础。
基金supported by fellowship to a grant from CRT Foundation,No.1393-2017(to LT)grants from the Fondazione Cariplo,Nos.2013-0795(to AAG),2014-1094(to DL)grants from The Universitàdel Piemonte Orientale,Nos.FAR-2016(to DL),FAR-2019(to DL)。
文摘Alzheimer's disease(AD)is characterized by complex etiology,long-lasting pathogenesis,and celltype-specific alterations.Currently,there is no cure for AD,emphasizing the urgent need for a comprehensive understanding of cell-specific pathology.Astrocytes,principal homeostatic cells of the central nervous system,are key players in the pathogenesis of neurodegenerative diseases,including AD.Cellular models greatly facilitate the investigation of cell-specific pathological alterations and the dissection of molecular mechanisms and pathways.Tumor-derived and immortalized astrocytic cell lines,alongside the emerging technology of adult induced pluripotent stem cells,are widely used to study cellular dysfunction in AD.Surprisingly,no stable cell lines were available from genetic mouse AD models.Recently,we established immortalized hippocampal astroglial cell lines from amyloid-βprecursor protein/presenilin-1/Tau triple-transgenic(3xTg)-AD mice(denominated as wild type(WT)-and 3Tg-iAstro cells)using retrovirus-mediated transduction of simian virus 40 large T-antigen and propagation without clonal selection,thereby maintaining natural heterogeneity of primary cultures.Several groups have successfully used 3Tg-iAstro cells for single-cell and omics approaches to study astrocytic AD-related alterations of calcium signaling,mitochondrial dysfunctions,disproteostasis,altered homeostatic and signaling support to neurons,and blood-brain barrier models.Here we provide a comparative overview of the most used models to study astrocytes in vitro,such as primary culture,tumor-derived cell lines,immortalized astroglial cell lines,and induced pluripotent stem cell-derived astrocytes.We conclude that immortalized WT-and 3Tg-iAstro cells provide a noncompetitive but complementary,low-cost,easy-to-handle,and versatile cellular model for dissection of astrocyte-specific AD-related alterations and preclinical drug discovery.
文摘真核生物细胞中,双层膜细胞器线粒体会进行持续的分裂与融合,从而改变自身形态来满足细胞在不同生长条件下的能量代谢需求.除此之外,线粒体的动态与功能还依赖于与其他细胞器的互作及一些代谢产物在互作过程中的双向交流.与线粒体互作的细胞器包括脂滴、过氧化物酶体、液泡和内质网等.在真菌细胞中,线粒体与内质网的互作由存在二者之间的内质网-线粒体接触复合物(ER and mitochondria encounter structure,ERMES)介导.ERMES复合物对于维持线粒体的形态和功能至关重要,其破坏会影响线粒体的动态、钙离子信号、磷脂组分的转运、真菌耐药性和致病真菌的毒力等.本文着重对ERMES复合物在真菌细胞中的组装、功能及其组装调控机制进行系统的总结和讨论.
