BACKGROUND： Neural stem cell （NSC） survival is closely associated with cell apoptosis in ischemic-hypoxic regions following transplantation. Numerous studies have revealed that X-box binding protein 1 （XBP1） is a...BACKGROUND： Neural stem cell （NSC） survival is closely associated with cell apoptosis in ischemic-hypoxic regions following transplantation. Numerous studies have revealed that X-box binding protein 1 （XBP1） is a transcription factor during endoplasmic reticulum unfolded protein response and is essential for cell survival, differentiation, and anti-apoptotic effects. OBJECTIVE： To determine the effects of the XBP1 gene on NSC proliferation and apoptosis under hypoxic conditions following XBP1 gene transfection into rat embryonic hippocampal NSCs using recombinant adenovirus vector. DESIGN, TIME AND SETTING： In vitro experiments were performed at the Laboratory of Cell Biology of Jilin University and Laboratory of Proteomics, Department of Neurology, Jilin University China from September 2008 to November 2009. MATERIALS： Recombinant adenovirus package XBP1 gene and Ad-XBPl-enhanced green fluorescent protein plasmid （Guangzhou Easywin BioMed Technology, China）, rabbit anti-XBP1 and its target gene estrogen receptor degradation-enhancing a-mannosidase-like protein （EDEM） glucose-regulated protein 78 （GRP78）, anti-apoptotic molecule Bcl-2 and proapoptotic molecule Bax polyclonal antibody （Santa Cruz Biotechnology, Inc., Santa Cruz, CA, USA）, and COCI2 （Sigma, St. Louis, MO, USA） were used in the present study. METHODS： Hippocampi from embryonic, Sprague Dawley rats on gestational day 16 were harvested for NSC isolation and cloning, followed by immunofluorescence for Nestin and sub-culturing. The recombinant adenovirus Ad-XBPl-enhanced green fluorescent protein plasmid was transfected into rat embryonic hippocampal NSCs, and then CoCl2 was applied to induce hypoxia. MAIN OUTCOME MEASURES： Cell quantification and 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide colorimetric assay were utilized to detect proliferation in XBPl-transfected NSCs for 7 consecutive days. Western blot assay was utilized to quantify XBP1 GRP78, EDEM, Bcl-2, and Bax expression. Flow cytometry was used to measure apoptosis. RESULTS： NSC proliferation was significantly enhanced following XBP1 gene transfection （P 〈 0.05）. Under hypoxic conditions, GRP78, EDEM, and Bcl-2 levels increased, but Bax levels decreased. In addition, NSC apoptosis decreased following transfection （P 〈 0.05）. CONCLUSION： The XBP1 gene was successfully transfected into rat embryonic hippocampal NSCs using a recombinant adenovirus vector. NSC proliferation following transfection, as well as anti-apoptotic effects under hypoxia, was significantly increased.展开更多
目的:探讨富含丝氨酸结构域1的RNA结合蛋白(RNA-binding protein with serine-rich domain 1,RNPS1)在胰腺癌进展中的作用及可能分子机制。方法:免疫组织化学与免疫荧光检测RNPS1与Notch3在胰腺癌组织及癌旁组织的表达;RTq PCR、免疫荧...目的:探讨富含丝氨酸结构域1的RNA结合蛋白(RNA-binding protein with serine-rich domain 1,RNPS1)在胰腺癌进展中的作用及可能分子机制。方法:免疫组织化学与免疫荧光检测RNPS1与Notch3在胰腺癌组织及癌旁组织的表达;RTq PCR、免疫荧光检测RNPS1与Notch3在胰腺癌细胞中的表达情况;Hoechst与CCK-8实验检测胰腺癌细胞凋亡与增殖;划痕实验与transwell实验检测胰腺癌细胞迁移与侵袭能力;Western blot实验检测胰腺癌细胞中N-Cadherin和E-Cadherin的表达;Western blot与RT-q PCR实验检测胰腺癌细胞中Notch3与HEY1的表达。结果:与癌旁组织与正常细胞系相比较,RNPS1与Notch3在胰腺癌组织中及胰腺癌细胞的表达均增高(F=121.612、34.649,均P<0.05);与对照组相比较,敲低RNPS1抑制生物标志物N-Cadherin的表达(t=39.922,P<0.05),促进E-Cadherin的表达(t=8.281,P<0.05),敲低RNPS1可减弱癌细胞的生存、迁移侵袭的能力(t=2.017、4.874、19.747,均P<0.05,),促进了细胞凋亡(t=33.673,P<0.05);敲低RNPS1降低了癌细胞中Notch3与HEY1的表达(t=17.546、6.258,均P<0.05)。结论:RNPS1的表达与胰腺癌细胞生存、恶性表型有关,RNPS1可能通过调控Notch3/HEY1信号通路促进胰腺癌细胞的生存及肿瘤进展。展开更多
We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repet...We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains unclear.In this study,we first used an HT22 scratch injury model to mimic traumatic brain injury,then co-cultured the HT22 cells with BV2 microglia expressing high levels of miR-124-3p.We found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum stress.Furthermore,luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α,while an IRE1αfunctional salvage experiment confirmed that miR-124-3p targeted IRE1αand reduced its expression,thereby inhibiting endoplasmic reticulum stress in injured neurons.Finally,we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly reduced.These findings suggest that,after repetitive mild traumatic brain injury,miR-124-3 can be transferred from microglia-derived exosomes to injured neurons,where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress.Therefore,microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury.展开更多
胆管癌是一种起病隐匿、侵袭性强、致死率高的原发性恶性肿瘤。多聚嘧啶区结合蛋白1(polypyrimidine tract-binding protein 1,PTBP1)已被报道,在多种类型肿瘤组织中异常高表达并参与癌症进展,但其在胆管癌中的作用仍未见报道。该研究...胆管癌是一种起病隐匿、侵袭性强、致死率高的原发性恶性肿瘤。多聚嘧啶区结合蛋白1(polypyrimidine tract-binding protein 1,PTBP1)已被报道,在多种类型肿瘤组织中异常高表达并参与癌症进展,但其在胆管癌中的作用仍未见报道。该研究旨在探讨PTBP1在胆管癌中的生物学功能,并初步解析其分子机制。本文利用公开的癌症基因组图谱(the cancer genome atlas,TCGA)数据,分析了胆管癌及癌旁组织中的PTBP1 mRNA表达水平。结果显示,PTBP1在胆管癌组织中的表达水平显著高于癌旁组织(P<0.05)。随后,在胆管癌细胞系RBE和HuH28中,通过CCK-8和细胞平板克隆实验,评价了PTBP1对胆管癌细胞生长能力的影响。结果显示,过表达PTBP1可显著促进胆管癌细胞的生长(P<0.01),而敲低PTBP1显著抑制胆管癌细胞的生长(P<0.001)。Transwell和Invasion实验结果显示,过表达PTBP1可显著促进胆管癌细胞的迁移和侵袭(P<0.001),而敲低PTBP1显著抑制胆管癌细胞的迁移和侵袭(P<0.001)。转录物组测序和通路富集分析结果显示,在胆管癌细胞中,敲低PTBP1后上调表达的基因显著富集于p53信号通路;而下调表达的基因显著富集于胆固醇代谢、Rho GTPase和TGF-β等信号通路。基于上述转录物组测序数据,本文还分析发现,敲低PTBP1可导致一系列基因发生异常的mRNA可变剪接事件,例如参与TGF-β调控的TGIF1及与p53活性相关的GNAS基因等。综上所述,PTBP1可能通过调控一系列基因的可变剪接而影响多个癌症相关的信号通路,从而促进胆管癌的进展。展开更多
The retina is one of the most energy demanding tissues in the body. Like most neurons in the central nervous system, retinal neurons consume high amounts of adenosine-5′-triphosphate（ATP） to generate visual signal ...The retina is one of the most energy demanding tissues in the body. Like most neurons in the central nervous system, retinal neurons consume high amounts of adenosine-5′-triphosphate（ATP） to generate visual signal and transmit the information to the brain. Disruptions in retinal metabolism can cause neuronal dysfunction and degeneration resulting in severe visual impairment and even blindness. The homeostasis of retinal metabolism is tightly controlled by multiple signaling pathways, such as the unfolded protein response（UPR）, and the close interactions between retinal neurons and other retinal cell types including vascular cells and Müller glia. The UPR is a highly conserved adaptive cellular response and can be triggered by many physiological stressors and pathophysiological conditions. Activation of the UPR leads to changes in glycolytic rate, ATP production, de novo serine synthesis, and the hexosamine biosynthetic pathway, which are considered critical components of Müller glia metabolism and provide metabolic support to surrounding neurons. When these pathways are disrupted, neurodegeneration occurs rapidly. In this review, we summarize recent advance in studies of the UPR in Müller glia and highlight the potential role of the UPR in retinal degeneration through regulation of Müller glia metabolism.展开更多
Controlled gene regulation during gamete development is vital for maintaining reproductive potential. During the complex process of mammalian spermatogenesis, male germ cells experience extended periods of the inactiv...Controlled gene regulation during gamete development is vital for maintaining reproductive potential. During the complex process of mammalian spermatogenesis, male germ cells experience extended periods of the inactive transcription despite heavy translational requirements for continued growth and differentiation. Hence, spermatogenesis is highly reliant on mechanisms of posttranscriptional regulation of gene expression, facilitated by RNA binding proteins （RBPs）, which remain abundantly expressed throughout this process. One such group of proteins is the Musashi family, previously identified as critical regulators of testis germ cell development and meiosis in Drosophila, and also shown to be vital to sperm development and reproductive potential in the mouse. This review describes the role and function of RBPs our recent knowledge of the Musashi proteins in spermatogenesis. within the scope of male germ cell development, focusing on The functional mechanisms utilized by RBPs within the cell are outlined in depth, and the significance of sub-cellular localization and stage-specific expression in relation to the mode and impact of posttranscriptional regulation is also highlighted. We emphasize the historical role of the Musashi family of RBPs in stem cell function and cell fate determination, as originally characterized in Drosophila and Xenopus, and conclude with our current understanding of the differential roles and functions of the mammalian Musashi proteins, Musashi-1 and Musashi-2, with a primary focus on our findings in spermatogenesis. This review highlights both the essential contribution of RBPs to posttranscriptional regulation and the importance of the Musashi family as master regulators of male gamete development.展开更多
AIM: To explore the changes of X-box binding protein 1splicing(XBP1s) and inflammatory cytokine expression in patients with ulcerative colitis(UC) in response to endoplasmic reticulum stress(ERS).METHODS: Reverse tran...AIM: To explore the changes of X-box binding protein 1splicing(XBP1s) and inflammatory cytokine expression in patients with ulcerative colitis(UC) in response to endoplasmic reticulum stress(ERS).METHODS: Reverse transcription polymerase chain reaction and quantitative polymerase chain reaction were performed to detect the forms of XBP1 s and the expression of interleukin(IL)-2, interferon(IFN)-γ, and IL-17α. Differences between patients with UC and normal subjects were then determined.RESULTS: Mononuclear cells of the peripheral blood of normal subjects and UC patients with were stimulated with no drugs(control), phytohemagglutinin(PHA), thapsigargin(TG), or both PHA and TG. XBP1 s in patients with UC exhibited splicing, which was greater with co-stimulation than single stimulation. Costimulation increased the expression level of IL-2, IFN-γ, and IL-17α.CONCLUSION: The T lymphocytes of both normal subjects and patients with UC responded to ERS by activating the XBP1s-mediated signalling pathway, upregulating the expression of inflammatory cytokines, and increasing the occurrence of inflammation. The mononuclear cells in the peripheral blood of patients with UC were more sensitive to ERS than those in the peripheral blood of normal subjects.展开更多
剪切型X盒结合蛋白1(spliced X-box binding protein 1,XBP1S)是内质网应激关键信号分子。有研究表明XBP1S在肾脏系膜细胞具有抗氧化应激和抗凋亡作用,而氧化应激是肾纤维化发生发展重要因素。缬沙坦(valsartan)具有改善肾纤维化作用。...剪切型X盒结合蛋白1(spliced X-box binding protein 1,XBP1S)是内质网应激关键信号分子。有研究表明XBP1S在肾脏系膜细胞具有抗氧化应激和抗凋亡作用,而氧化应激是肾纤维化发生发展重要因素。缬沙坦(valsartan)具有改善肾纤维化作用。本研究旨在探讨valsartan能否通过XBP1S进而影响肾间质纤维化发展。C57BL/6J小鼠行左侧输尿管结扎(unilateral ureteral obstruction,UUO)制作肾纤维化模型,valsartan组于造模前1 d起每天给予valsartan(20 mg/kg)灌胃,UUO组和对照组给予等容积生理盐水灌胃,于手术后第7天处死动物,取左侧肾。HE、Masson和天狼星红(Sirius red)染色观察肾间质纤维化;免疫组化染色观察XBP1S在肾间质表达;Western blot检测XBP1S、纤维连接蛋白(fibronectin)、α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、BAX和BCL2蛋白水平;实时荧光定量PCR检测NADPH氧化酶亚基p47-phox与p67-phox m RNA水平。结果显示,与对照组相比,UUO组XBP1S蛋白水平明显降低,valsartan明显升高UUO小鼠XBP1S蛋白水平;HE、Masson和Sirius red染色结果显示valsartan明显改善UUO小鼠肾间质纤维化;Western blot结果显示valsartan明显降低UUO小鼠fibronectin、BAX/BCL2、α-SMA蛋白水平。实时荧光定量PCR结果显示:UUO组p47-phox与p67-phox m RNA水平明显较对照组升高,相比较于UUO组,valsartan明显降低UUO小鼠p47-phox与p67-phox m RNA水平。以上结果提示,XBP1S蛋白水平下调与UUO模型的肾间质纤维化有关,其机制可能与XBP1S抗氧化应激相关。展开更多
文摘BACKGROUND： Neural stem cell （NSC） survival is closely associated with cell apoptosis in ischemic-hypoxic regions following transplantation. Numerous studies have revealed that X-box binding protein 1 （XBP1） is a transcription factor during endoplasmic reticulum unfolded protein response and is essential for cell survival, differentiation, and anti-apoptotic effects. OBJECTIVE： To determine the effects of the XBP1 gene on NSC proliferation and apoptosis under hypoxic conditions following XBP1 gene transfection into rat embryonic hippocampal NSCs using recombinant adenovirus vector. DESIGN, TIME AND SETTING： In vitro experiments were performed at the Laboratory of Cell Biology of Jilin University and Laboratory of Proteomics, Department of Neurology, Jilin University China from September 2008 to November 2009. MATERIALS： Recombinant adenovirus package XBP1 gene and Ad-XBPl-enhanced green fluorescent protein plasmid （Guangzhou Easywin BioMed Technology, China）, rabbit anti-XBP1 and its target gene estrogen receptor degradation-enhancing a-mannosidase-like protein （EDEM） glucose-regulated protein 78 （GRP78）, anti-apoptotic molecule Bcl-2 and proapoptotic molecule Bax polyclonal antibody （Santa Cruz Biotechnology, Inc., Santa Cruz, CA, USA）, and COCI2 （Sigma, St. Louis, MO, USA） were used in the present study. METHODS： Hippocampi from embryonic, Sprague Dawley rats on gestational day 16 were harvested for NSC isolation and cloning, followed by immunofluorescence for Nestin and sub-culturing. The recombinant adenovirus Ad-XBPl-enhanced green fluorescent protein plasmid was transfected into rat embryonic hippocampal NSCs, and then CoCl2 was applied to induce hypoxia. MAIN OUTCOME MEASURES： Cell quantification and 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide colorimetric assay were utilized to detect proliferation in XBPl-transfected NSCs for 7 consecutive days. Western blot assay was utilized to quantify XBP1 GRP78, EDEM, Bcl-2, and Bax expression. Flow cytometry was used to measure apoptosis. RESULTS： NSC proliferation was significantly enhanced following XBP1 gene transfection （P 〈 0.05）. Under hypoxic conditions, GRP78, EDEM, and Bcl-2 levels increased, but Bax levels decreased. In addition, NSC apoptosis decreased following transfection （P 〈 0.05）. CONCLUSION： The XBP1 gene was successfully transfected into rat embryonic hippocampal NSCs using a recombinant adenovirus vector. NSC proliferation following transfection, as well as anti-apoptotic effects under hypoxia, was significantly increased.
文摘目的:探讨富含丝氨酸结构域1的RNA结合蛋白(RNA-binding protein with serine-rich domain 1,RNPS1)在胰腺癌进展中的作用及可能分子机制。方法:免疫组织化学与免疫荧光检测RNPS1与Notch3在胰腺癌组织及癌旁组织的表达;RTq PCR、免疫荧光检测RNPS1与Notch3在胰腺癌细胞中的表达情况;Hoechst与CCK-8实验检测胰腺癌细胞凋亡与增殖;划痕实验与transwell实验检测胰腺癌细胞迁移与侵袭能力;Western blot实验检测胰腺癌细胞中N-Cadherin和E-Cadherin的表达;Western blot与RT-q PCR实验检测胰腺癌细胞中Notch3与HEY1的表达。结果:与癌旁组织与正常细胞系相比较,RNPS1与Notch3在胰腺癌组织中及胰腺癌细胞的表达均增高(F=121.612、34.649,均P<0.05);与对照组相比较,敲低RNPS1抑制生物标志物N-Cadherin的表达(t=39.922,P<0.05),促进E-Cadherin的表达(t=8.281,P<0.05),敲低RNPS1可减弱癌细胞的生存、迁移侵袭的能力(t=2.017、4.874、19.747,均P<0.05,),促进了细胞凋亡(t=33.673,P<0.05);敲低RNPS1降低了癌细胞中Notch3与HEY1的表达(t=17.546、6.258,均P<0.05)。结论:RNPS1的表达与胰腺癌细胞生存、恶性表型有关,RNPS1可能通过调控Notch3/HEY1信号通路促进胰腺癌细胞的生存及肿瘤进展。
基金supported by the Haihe Laboratory of Cell Ecosystem Innovation Fund,No.22HHXBSS00047(to PL)the National Natural Science Foundation of China,Nos.82072166(to PL),82071394(to XG)+4 种基金Science and Technology Planning Project of Tianjin,No.20YFZCSY00030(to PL)Science and Technology Project of Tianjin Municipal Health Commission,No.TJWJ2021QN005(to XG)Tianjin Key Medical Discipline(Specialty)Construction Project,No.TJYXZDXK-006ATianjin Municipal Education Commission Scientific Research Program Project,No.2020KJ164(to JZ)China Postdoctoral Science Foundation,No.2022M712392(to ZY).
文摘We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains unclear.In this study,we first used an HT22 scratch injury model to mimic traumatic brain injury,then co-cultured the HT22 cells with BV2 microglia expressing high levels of miR-124-3p.We found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum stress.Furthermore,luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α,while an IRE1αfunctional salvage experiment confirmed that miR-124-3p targeted IRE1αand reduced its expression,thereby inhibiting endoplasmic reticulum stress in injured neurons.Finally,we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly reduced.These findings suggest that,after repetitive mild traumatic brain injury,miR-124-3 can be transferred from microglia-derived exosomes to injured neurons,where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress.Therefore,microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury.
文摘胆管癌是一种起病隐匿、侵袭性强、致死率高的原发性恶性肿瘤。多聚嘧啶区结合蛋白1(polypyrimidine tract-binding protein 1,PTBP1)已被报道,在多种类型肿瘤组织中异常高表达并参与癌症进展,但其在胆管癌中的作用仍未见报道。该研究旨在探讨PTBP1在胆管癌中的生物学功能,并初步解析其分子机制。本文利用公开的癌症基因组图谱(the cancer genome atlas,TCGA)数据,分析了胆管癌及癌旁组织中的PTBP1 mRNA表达水平。结果显示,PTBP1在胆管癌组织中的表达水平显著高于癌旁组织(P<0.05)。随后,在胆管癌细胞系RBE和HuH28中,通过CCK-8和细胞平板克隆实验,评价了PTBP1对胆管癌细胞生长能力的影响。结果显示,过表达PTBP1可显著促进胆管癌细胞的生长(P<0.01),而敲低PTBP1显著抑制胆管癌细胞的生长(P<0.001)。Transwell和Invasion实验结果显示,过表达PTBP1可显著促进胆管癌细胞的迁移和侵袭(P<0.001),而敲低PTBP1显著抑制胆管癌细胞的迁移和侵袭(P<0.001)。转录物组测序和通路富集分析结果显示,在胆管癌细胞中,敲低PTBP1后上调表达的基因显著富集于p53信号通路;而下调表达的基因显著富集于胆固醇代谢、Rho GTPase和TGF-β等信号通路。基于上述转录物组测序数据,本文还分析发现,敲低PTBP1可导致一系列基因发生异常的mRNA可变剪接事件,例如参与TGF-β调控的TGIF1及与p53活性相关的GNAS基因等。综上所述,PTBP1可能通过调控一系列基因的可变剪接而影响多个癌症相关的信号通路,从而促进胆管癌的进展。
基金supported,in part,by NIH/NEI grants EY019949 and EY025061an Unrestricted Grant to the Department of Ophthalmology,SUNY-Buffalo,from Research to Prevent Blindness
文摘The retina is one of the most energy demanding tissues in the body. Like most neurons in the central nervous system, retinal neurons consume high amounts of adenosine-5′-triphosphate（ATP） to generate visual signal and transmit the information to the brain. Disruptions in retinal metabolism can cause neuronal dysfunction and degeneration resulting in severe visual impairment and even blindness. The homeostasis of retinal metabolism is tightly controlled by multiple signaling pathways, such as the unfolded protein response（UPR）, and the close interactions between retinal neurons and other retinal cell types including vascular cells and Müller glia. The UPR is a highly conserved adaptive cellular response and can be triggered by many physiological stressors and pathophysiological conditions. Activation of the UPR leads to changes in glycolytic rate, ATP production, de novo serine synthesis, and the hexosamine biosynthetic pathway, which are considered critical components of Müller glia metabolism and provide metabolic support to surrounding neurons. When these pathways are disrupted, neurodegeneration occurs rapidly. In this review, we summarize recent advance in studies of the UPR in Müller glia and highlight the potential role of the UPR in retinal degeneration through regulation of Müller glia metabolism.
文摘Controlled gene regulation during gamete development is vital for maintaining reproductive potential. During the complex process of mammalian spermatogenesis, male germ cells experience extended periods of the inactive transcription despite heavy translational requirements for continued growth and differentiation. Hence, spermatogenesis is highly reliant on mechanisms of posttranscriptional regulation of gene expression, facilitated by RNA binding proteins （RBPs）, which remain abundantly expressed throughout this process. One such group of proteins is the Musashi family, previously identified as critical regulators of testis germ cell development and meiosis in Drosophila, and also shown to be vital to sperm development and reproductive potential in the mouse. This review describes the role and function of RBPs our recent knowledge of the Musashi proteins in spermatogenesis. within the scope of male germ cell development, focusing on The functional mechanisms utilized by RBPs within the cell are outlined in depth, and the significance of sub-cellular localization and stage-specific expression in relation to the mode and impact of posttranscriptional regulation is also highlighted. We emphasize the historical role of the Musashi family of RBPs in stem cell function and cell fate determination, as originally characterized in Drosophila and Xenopus, and conclude with our current understanding of the differential roles and functions of the mammalian Musashi proteins, Musashi-1 and Musashi-2, with a primary focus on our findings in spermatogenesis. This review highlights both the essential contribution of RBPs to posttranscriptional regulation and the importance of the Musashi family as master regulators of male gamete development.
基金Beijing Municipal Natural Scientific Research Foundation,No.7132175
文摘AIM: To explore the changes of X-box binding protein 1splicing(XBP1s) and inflammatory cytokine expression in patients with ulcerative colitis(UC) in response to endoplasmic reticulum stress(ERS).METHODS: Reverse transcription polymerase chain reaction and quantitative polymerase chain reaction were performed to detect the forms of XBP1 s and the expression of interleukin(IL)-2, interferon(IFN)-γ, and IL-17α. Differences between patients with UC and normal subjects were then determined.RESULTS: Mononuclear cells of the peripheral blood of normal subjects and UC patients with were stimulated with no drugs(control), phytohemagglutinin(PHA), thapsigargin(TG), or both PHA and TG. XBP1 s in patients with UC exhibited splicing, which was greater with co-stimulation than single stimulation. Costimulation increased the expression level of IL-2, IFN-γ, and IL-17α.CONCLUSION: The T lymphocytes of both normal subjects and patients with UC responded to ERS by activating the XBP1s-mediated signalling pathway, upregulating the expression of inflammatory cytokines, and increasing the occurrence of inflammation. The mononuclear cells in the peripheral blood of patients with UC were more sensitive to ERS than those in the peripheral blood of normal subjects.
基金supported by grants from the National Natural Science Foundation of China(No.81400695)the Anhui Provincial Natural Science Foundation,China(No.1508085QH153)the Foundation of Wannan Medical College,China(No.WK201401)
文摘剪切型X盒结合蛋白1(spliced X-box binding protein 1,XBP1S)是内质网应激关键信号分子。有研究表明XBP1S在肾脏系膜细胞具有抗氧化应激和抗凋亡作用,而氧化应激是肾纤维化发生发展重要因素。缬沙坦(valsartan)具有改善肾纤维化作用。本研究旨在探讨valsartan能否通过XBP1S进而影响肾间质纤维化发展。C57BL/6J小鼠行左侧输尿管结扎(unilateral ureteral obstruction,UUO)制作肾纤维化模型,valsartan组于造模前1 d起每天给予valsartan(20 mg/kg)灌胃,UUO组和对照组给予等容积生理盐水灌胃,于手术后第7天处死动物,取左侧肾。HE、Masson和天狼星红(Sirius red)染色观察肾间质纤维化;免疫组化染色观察XBP1S在肾间质表达;Western blot检测XBP1S、纤维连接蛋白(fibronectin)、α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)、BAX和BCL2蛋白水平;实时荧光定量PCR检测NADPH氧化酶亚基p47-phox与p67-phox m RNA水平。结果显示,与对照组相比,UUO组XBP1S蛋白水平明显降低,valsartan明显升高UUO小鼠XBP1S蛋白水平;HE、Masson和Sirius red染色结果显示valsartan明显改善UUO小鼠肾间质纤维化;Western blot结果显示valsartan明显降低UUO小鼠fibronectin、BAX/BCL2、α-SMA蛋白水平。实时荧光定量PCR结果显示:UUO组p47-phox与p67-phox m RNA水平明显较对照组升高,相比较于UUO组,valsartan明显降低UUO小鼠p47-phox与p67-phox m RNA水平。以上结果提示,XBP1S蛋白水平下调与UUO模型的肾间质纤维化有关,其机制可能与XBP1S抗氧化应激相关。
