核蛋白TAR DNA/RNA结合蛋白43与小鼠肌萎缩侧索硬化症的关系

目的利用HB9启动子构建小鼠脊髓运动神经元特异表达人类TAR DNA/RNA结合蛋白43(hTDP-43)突变转基因小鼠,建立肌萎缩侧索硬化症(ALS)疾病模型,探究hTDP-43突变导致ALS发生的机制。方法体外构建HB9启动子连接突变hTDP-43载体,通过原核注射制备并筛选阳性转基因小鼠品系(Q331K位点和M337V位点突变各8~10只)。通过步态分析、转棒疲劳仪实验和悬挂实验检测小鼠运动能力;通过免疫组织化学法、免疫荧光染色和Western blotting分别检测hTDP-43、磷酸化hTDP-43(p-hTDP-43),Caspase-3、剪切Caspase-3(cleaved Caspase-3)、泛素蛋白、β-微管蛋白Ⅲ(Tuj1)、Ki67和细胞周期依赖性激酶5(CDK5)蛋白的表达情况。结果脊髓运动神经元表达突变hTDP-43蛋白的转基因小鼠双后肢向躯干侧回缩,运动机能随月龄增加呈现进程性减退。转基因小鼠脊髓运动神经元可见hTDP-43,p-hTDP43,Caspase-3,cleaved Caspase-3阳性染色和泛素蛋白阳性包涵体,体外分离培养脊髓胸腰段运动神经元发现hTDP-43和泛素蛋白共定位于胆碱乙酰基转位酶(ChAT)阳性的运动神经元,并伴随CDK5异位表达。结论小鼠脊髓运动神经元表达突变的hTDP-43蛋白,可促使分化的成熟神经元重新进入细胞周期,导致ALS发生。

TAR DNA结合蛋白43在肌萎缩侧索硬化症中致病机制的研究进展

肌萎缩侧索硬化症(ALS)是一种主要累及上、下运动神经元的神经系统退行性疾病。TAR DNA结合蛋白43(TDP-43)蛋白是大部分ALS患者中特征性的病理性聚集蛋白。TDP-43蛋白致ALS的机制尚不明确,可归纳为以下两种假说:"功能缺失"和"功能获得"。相关机制有:①TDP-43蛋白稳态与自噬密切相关;②TDP-43蛋白与RNA结合,干扰RNA代谢,并与应激颗粒的形成密切相关;③TDP-43蛋白聚集与线粒体功能障碍相互影响;④TDP-43蛋白异常聚集影响细胞骨架结构,致轴突运输异常,并引起神经肌肉肉接头功能障碍;⑤外泌体能降解胞浆TDP-43蛋白聚集并促进其在细胞之间的扩散等。本文就TDP-43蛋白致ALS的机制的最新进展做一综述。

TARDNA结合蛋白-43和肉瘤融合／脂肪肉瘤转运蛋白与两种神经系统变性疾病关系的研究进展

神经系统变性疾病是一类由神经元变性和继发性脱髓鞘引起的慢性病,近来研究显示TAR DNA结合蛋白-43(TDP-43)和肉瘤融合/脂肪肉瘤转运蛋白(FUS/TLS)与肌萎缩侧索硬化(ALS)和额颞叶痴呆(FTD)有关。与TDP-43和FUS/TLS相关的基因突变可导致其蛋白表达异常,进而引起细胞骨架蛋白降解和RNA代谢障碍。TDP-43和FUS/TLS相关ALS与FTD的病理学表现也具有相似的形式。虽然TDP-43与FUS/TLS之间的相互作用尚不清楚,但可以推测与二者相关的神经系统变性疾病可能具有相同的发病机制。

TAR DNA结合蛋白43的表达与脑损伤的相关性研究进展

TAR DNA结合蛋白43(TAR DNA-binding domain protein 43,TDP-43)是一种高度保守、广泛表达的核蛋白。如今发现TDP-43在大多数神经退行性疾病如阿尔茨海默症患者中表达,为神经退行性疾病相关的标记蛋白。本文从目前国内外的研究现状出发,围绕TDP-43的表达与脑损伤的相关性,在对TDP-43生物学特性认识的基础上,着重探讨TDP-43在急、慢性颅脑损伤中的特殊表达与作用,从而探索TDP-43在法医病理学中确定死亡原因、判定致伤致残情况的可行性。

肌萎缩侧索硬化症患者骨骼肌神经末梢中磷酸化TAR DNA结合蛋白43和泛素的表达

目的:检测肌萎缩侧索硬化症(ALS)患者骨骼肌神经末梢中磷酸化TAR DNA结合蛋白43(p TDP-43)和泛素(Ub)的表达情况,探讨其在ALS发病中的作用机制。方法:收集30例ALS患者及22例对照的骨骼肌标本,采用免疫组化法检测p TDP-43及Ub的表达情况。结果:ALS组、对照组p TDP-43、Ub阳性表达率分别为46. 7%、0. 0%和60. 0%、0. 0%,差异有统计学意义(P <0. 001)。结论:骨骼肌神经末梢是部分ALS患者除神经元及神经胶质细胞以外的p TDP-43病理沉积部位,可能参与了ALS的发病。

Targeted Degradation of DNA/RNA Binding Proteins via Covalent Hydrophobic Tagging

Targeted protein degradation(TPD)holds great promise for biological inquiry and therapeutic development.However,it still remains elusive to destruct DNA/RNA binding proteins(DBPs/RBPs)previously deemed undruggable.Herein,we report ligandassisted covalent hydrophobic tagging(LACHT)as a modular strategy for TPD of these difficult-totarget proteins.Guided by a noncovalent protein ligand,LACHT leverages a reactive N-acyl-N-alkyl sulfonamide group to covalently label the protein target with a hydrophobic adamantane,which further engages the cellular quality control mechanism to induce proteolytic degradation.Using a smallmolecule ligand,we demonstrated that LACHT allowed TPD of a DBP,bromodomain-containing protein 4,in human leukemia cells with high efficiency.Mechanistic studies revealed that LACHT-mediated TPD dependent on ligand-directed irreversible tagging and the covalently labeled proteins underwent polyubiquitination before removal through both the proteasome and the lysosome.Furthermore,when an RNA ligand was employed,we showed that LACHT also enabled TPD of an RBP,Lin28a,leading to upregulation of its downstream let-7 miRNA.This study thus provides a generalizable platform to expand the TPD toolbox for biomedical applications.

Presence/Absence of Two Types of Z-DNA Binding Domains in the Genomes of Organisms from Archaea, Bacteria, and Eukaryotes and Its Implications

We conducted genome sequence analysis to examine the presence/absence of two types of Z-DNA binding domains in various organisms. We examined 68 organisms from archaea, 914 organisms from bacteria, and 199 organisms from eukaryotes. RecA protein from Escherichia coli has a Z-DNA binding domain and this protein promotes homologous recombination. All the organisms examined had this domain. This result indicated that this domain is essential for all the organisms. RNA editing enzyme, adenosine deaminase from human has another type of Z-DNA binding domain. This domain was observed in some organisms of archaea, bacteria, and eukaryotes. The presence/absence of Z-DNA binding domain in adenosine deaminase indicated that gain and loss of this domain had occurred in the process of evolution. The implication of presence and absence of this domain is discussed in this study.

TARDNA结合蛋白43与泛素体外共相分离机制初步研究

目的探究TAR DNA结合蛋白43(TDP-43)与泛素共相分离的动态变化特征及机制。方法构建TDP-43全长及各结构域原核表达质粒,纯化泛素和TDP-43全长及各结构域截短体蛋白,构建泛素和TDP-43体外的相分离体系,利用荧光显微镜观测通过液-液相分离形成的液滴的动态特征。将泛素和TDP-43真核表达质粒转染入HEK293T细胞内表达,利用荧光显微镜观察TDP-43与泛素形成聚集体并通过pull-down实验检测TDP-43泛素化修饰。结果成功纯化得到泛素和TDP-43全长及各结构域截短体蛋白。体外相分离体系中发现TDP-43全长和CTD截短体蛋白能够与泛素发生共相分离,且延长孵育时间液滴最终变成流动性较差的聚集体。在细胞内共转染泛素和TDP-43质粒,二者形成不可溶的聚集体,应激条件下TDP-43能够被泛素化修饰。结论TDP-43能够与泛素蛋白发生共相分离,主要通过TDP-43的CTD结构域与泛素间的多价相互作用驱动,且该凝聚体液滴易形成流动性差的聚集体。在应激条件下,当细胞内蛋白稳态失衡时,TDP-43与泛素被募集到一起形成聚集体且聚集体内的TDP-43会被泛素化修饰。该研究揭示了TDP-43与泛素蛋白发生共相分离并发生液-固转化的基本机制。

Yinchenhao decoction attenuates obstructive jaundice-induced liver injury and hepatocyte apoptosis by suppressing protein kinase RNA-like endoplasmic reticulum kinase-induced pathway

BACKGROUND Chronic biliary obstruction results in ischemia and hypoxia of hepatocytes,and leads to apoptosis.Apoptosis is very important in regulating the homeostasis of the hepatobiliary system.Endoplasmic reticulum(ER)stress is one of the signaling pathways that induce apoptosis.Moreover,the protein kinase RNA-like endoplasmic reticulum kinase(PERK)-induced apoptotic pathway is the main way;but its role in liver injury remains unclear.Yinchenhao decoction(YCHD)is a traditional Chinese medicine formula that alleviates liver injury and apoptosis,yet its mechanism is unknown.We undertook this study to investigate the effects of YCHD on the expression of ER stress proteins and hepatocyte apoptosis in rats with obstructive jaundice(OJ).AIM To investigate whether YCHD can attenuate OJ-induced liver injury and hepatocyte apoptosis by inhibiting the PERK-CCAAT/enhancer-binding protein homologous protein(CHOP)-growth arrest and DNA damage-inducible protein 34(GADD34)pathway and B cell lymphoma/leukemia-2 related X protein(Bax)/B cell lymphoma/leukemia-2(Bcl-2)ratio.METHODS For in vivo experiments,30 rats were divided into three groups:control group,OJ model group,and YCHD-treated group.Blood was collected to detect the indicators of liver function,and liver tissues were used for histological analysis.For in vitro experiments,30 rats were divided into three groups:G1,G2,and G3.The rats in group G1 had their bile duct exposed without ligation,the rats in group G2 underwent total bile duct ligation,and the rats in group G3 were given a gavage of YCHD.According to the serum pharmacology,serum was extracted and centrifuged from the rat blood to cultivate the BRL-3A cells.Terminal deoxynucleotidyl transferase mediated dUTP nick end-labelling(TUNEL)assay was used to detect BRL-3A hepatocyte apoptosis.Alanine aminotransferase(ALT)and aspartate transaminase(AST)levels in the medium were detected.Western blot and quantitative real-time polymerase chain reaction(qRT-PCR)analyses were used to detect protein and gene expression levels of PERK,CHOP,GADD34,Bax,and Bcl-2 in the liver tissues and BRL-3A cells.RESULTS Biochemical assays and haematoxylin and eosin staining suggested severe liver function injury and liver tissue structure damage in the OJ model group.The TUNEL assay showed that massive BRL-3A rat hepatocyte apoptosis was induced by OJ.Elevated ALT and AST levels in the medium also demonstrated that hepatocytes could be destroyed by OJ.Western blot or qRT-PCR analyses showed that the protein and mRNA expression levels of PERK,CHOP,and GADD34 were significantly increased both in the rat liver tissue and BRL-3A rat hepatocytes by OJ.The Bax and Bcl-2 levels were increased,and the Bax/Bcl-2 ratio was also increased.When YCHD was used,the PERK,CHOP,GADD34,and Bax levels quickly decreased,while the Bcl-2 levels increased,and the Bax/Bcl-2 ratio decreased.CONCLUSION OJ-induced liver injury and hepatocyte apoptosis are associated with the activation of the PERK-CHOP-GADD34 pathway and increased Bax/Bcl-2 ratio.YCHD can attenuate these changes.

siRNA沉默染色质解旋酶DNA结合蛋白1对卵巢癌HO-8910PM细胞增殖、侵袭、迁移的影响

目的:探究siRNA沉默染色质解旋酶DNA结合蛋白1(CHD1L)对卵巢癌HO-8910PM细胞增殖、侵袭、迁移及相关分子如核因子κB(NF-κB)、基质金属蛋白酶(MMP)的影响。方法:将si-CHD1L、si-NC质粒转染至卵巢癌HO-8910PM细胞,命名为si-CHD1L组、si-NC组,以未经转染细胞作为对照组,实时荧光定量PCR(qRT-PCR)检测细胞CHD1L mRNA表达; CCK-8法检测细胞增殖抑制情况;划痕实验检测细胞迁移能力;Transwell小室系统检测细胞迁移、侵袭能力;蛋白免疫印迹(WB)检测NF-κB、MMP-2、MMP-9蛋白表达。结果:与对照组、si-NC组比较,si-CHD1L组细胞CHD1L mRNA表达降低(P<0.05),细胞增殖抑制率升高,细胞迁移能力降低,迁移、侵袭数量降低(P<0.05)。与对照组、si-NC组相比,si-CHD1L组NF-κB、MMP-2、MMP-9蛋白表达降低(P<0.05)。结论:siRNA沉默CHD1L能够抑制卵巢癌HO-8910PM细胞增殖、侵袭、迁移,并能抑制NF-κB、MMP蛋白的表达,为卵巢癌的靶向治疗提供一定的理论依据。

A candidate protective factor in amyotrophic lateral sclerosis:heterogenous nuclear ribonucleoprotein G

Heterogenous nuclear ribonucleoprotein G is down-regulated in the spinal cord of the Tg(SOD1*G93A)1Gur(TG)amyotrophic lateral sclerosis mouse model.However,most studies have only examined heterogenous nuclear ribonucleoprotein G expression in the amyotrophic lateral sclerosis model and heterogenous nuclear ribonucleoprotein G effects in amyotrophic lateral sclerosis pathogenesis such as in apoptosis are unknown.In this study,we studied the potential mechanism of heterogenous nuclear ribonucleoprotein G in neuronal death in the spinal cord of TG and wild-type mice and examined the mechanism by which heterogenous nuclear ribonucleoprotein G induces apoptosis.Heterogenous nuclear ribonucleoprotein G in spinal cord was analyzed using immunohistochemistry and western blotting,and cell proliferation and proteins(TAR DNA binding protein 43,superoxide dismutase 1,and Bax)were detected by the Cell Counting Kit-8 and western blot analysis in heterogenous nuclear ribonucleoprotein G siRNA-transfected PC12 cells.We analyzed heterogenous nuclear ribonucleoprotein G distribution in spinal cord in the amyotrophic lateral sclerosis model at various time points and the expressions of apoptosis and proliferation-related proteins.Heterogenous nuclear ribonucleoprotein G was mainly localized in neurons.Amyotrophic lateral sclerosis mice were examined at three stages:preonset(60-70 days),onset(90-100 days)and progression(120-130 days).The number of heterogenous nuclear ribonucleoprotein G-positive cells was significantly higher in the anterior horn of the lumbar spinal cord segment of TG mice at the preonset stage than that of control group but lower than that of the control group at the onset stage.The number of heterogenous nuclear ribonucleoprotein G-positive cells in both central canal and surrounding gray matter of the whole spinal cord of TG mice at the onset stage was significantly lower than that in the control group,whereas that of the lumbar spinal cord segment of TG mice was significantly higher than that in the control group at preonset stage and significantly lower than that in the control group at the progression stage.The numbers of heterogenous nuclear ribonucleoprotein G-positive cells in the posterior horn of cervical and thoracic segments of TG mice at preonset and progression stages were significantly lower than those in the control group.The expression of heterogenous nuclear ribonucleoprotein G in the cervical spinal cord segment of TG mice was significantly higher than that in the control group at the preonset stage but significantly lower at the progression stage.The expression of heterogenous nuclear ribonucleoprotein G in the thoracic spinal cord segment of TG mice was significantly increased at the preonset stage,significantly decreased at the onset stage,and significantly increased at the progression stage compared with the control group.heterogenous nuclear ribonucleoprotein G expression in the lumbar spinal cord segment of TG mice was significantly lower than that of the control group at the progression stage.After heterogenous nuclear ribonucleoprotein G gene silencing,PC12 cell survival was lower than that of control cells.Both TAR DNA binding protein 43 and Bax expressions were significantly increased in heterogenous nuclear ribonucleoprotein G-silenced cells compared with control cells.Our study suggests that abnormal distribution and expression of heterogenous nuclear ribonucleoprotein G might play a protective effect in amyotrophic lateral sclerosis development via preventing neuronal death by reducing abnormal TAR DNA binding protein 43 generation in the spinal cord.

TDP-43对氧糖剥夺诱导的小鼠HL-1心房肌细胞凋亡的影响及其机制

目的探讨TARDNA结合蛋白43(TDP-43)对氧糖剥夺(OGD)诱导小鼠HL-1心房肌细胞凋亡的影响及其机制。方法将体外培养的小鼠HL-1心房肌细胞分为:(1)对照组及不同OGD处理时间(2、4、8、16h)组,采用CCK-8法检测细胞活力,Westernblotting检测TDP-43蛋白表达水平,以此确定OGD诱导时间点用于后续研究;(2)对照组与OGD组,采用流式细胞术检测细胞凋亡率,JC-1染色法检测线粒体膜电位,化学发光法检测三磷酸腺苷(ATP)相对含量,微板法检测丙二醛(MDA)含量,WST-1法检测超氧化物歧化酶(SOD)含量。将转染慢病毒的小鼠HL-1心房肌细胞分为:(1)阴性对照慢病毒干预组(NC-shRNA)、TDP-43敲低慢病毒干预组(TDP-43-shRNA1、TDP-43-shRNA2、TDP-43-shRNA3),Westernblotting检测TDP-43蛋白表达水平,选择慢病毒敲低效率最高的TDP-43-shRNA用于后续试验;(2)NC-shRNA组、TDP-43-shRNA组、OGD+NC-shRNA组、OGD+TDP-43-shRNA组,在常氧条件和OGD条件下,采用流式细胞术检测细胞凋亡率,MitoTracker染色法检测线粒体形态,JC-1染色法检测线粒体膜电位,化学发光法检测ATP含量,流式细胞术检测活性氧(ROS)荧光强度,微板法检测MDA含量,WST-1法检测SOD含量。结果CCK-8法检测结果显示,随OGD时间的延长,小鼠HL-1心房肌细胞的活力逐渐下降;Westernblotting检测结果显示,TDP-43蛋白表达水平逐渐升高,两者均呈现较强的时间依赖性。与对照组比较,在OGD16h时小鼠HL-1心房肌细胞活力最低(P<0.05)、TDP-43蛋白表达量最高(P<0.05),据此后续实验选择OGD16h为诱导时间点。与对照组比较,OGD组细胞凋亡率、线粒体膜电位荧光强度比值、MDA含量升高,ATP相对含量、SOD含量降低,差异均有统计学意义(P<0.05)。Westernblotting检测结果显示,与NC-shRNA组比较,TDP-43-shRNA2组TDP-43蛋白表达水平降低最为明显(P<0.05),敲低效率最高,因此选择TDP-43-shRNA2进行后续实验。流式细胞术检测结果显示,在常氧条件下,与NC-shRNA组比较,TDP-43-shRNA组细胞凋亡率无明显变化(P>0.05);在OGD条件下,与OGD+NC-shRNA组比较,OGD+TDP-43-shRNA组细胞凋亡率降低(P<0.05)。MitoTracker染色结果显示,与NC-shRNA组比较,TDP-43-shRNA组线粒体形态完整,无明显变化;OGD+NC-shRNA组线粒体数量增多,多数为碎片状,分布散乱;与OGD+NC-shRNA组比较,OGD+TDP-43-shRNA组线粒体形态有所恢复。在常氧条件下,与NC-shRNA组比较,TDP-43-shRNA组线粒体膜电位荧光强度比值、ATP相对含量、ROS荧光强度、MDA含量、SOD含量均无明显变化(P>0.05);但在OGD条件下,与OGD+NC-shRNA组比较,OGD+TDP-43-shRNA组细胞线粒体膜电位荧光强度比值、ROS荧光强度、MDA含量降低,ATP相对含量、SOD含量升高,差异均有统计学意义(P<0.05)。结论TDP-43通过调控心肌细胞凋亡加重OGD诱导的线粒体功能障碍,因此,敲低TDP-43的表达有望成为缺血性心肌病的潜在治疗策略。

Targeting prion-like protein spreading in neurodegenerative diseases

The infectious template-mediated protein conversion is a unique mechanism for the onset of rare and fatal neurodegenerative disorders known as transmissible spongiform encephalopathies, or prion diseases, which affect humans and other animal species. However, emerging studies are now demonstrating prion-like mechanisms of self-propagation of protein misfolding in a number of common, non-infectious neurodegenerative diseases such as Alzheimer＇s disease and Parkinson＇s disease. It has been proposed that distinct and unrelated proteins（beta-amyloid, tau, α-synuclein, TAR DNA-binding protein 43 and huntingtin, etc.） associated with common neurodegenerative disorders can seed conversion and spread via cellto-cell transfer, sustaining the transmission of neurotoxic agents along a stereotypic route, sharing features at the heart of the intrinsic nature of prions. Here we review the most recent development on both the molecular mechanisms underlying the pathogenesis of prion-like neurodegenerative diseases as well as innovative methods and strategies for potential therapeutic applications.

TDP-43在男性不育中的研究进展

全世界大约有10%~15%的育龄夫妇婚后1年不孕不育。在不育的原因中,男性因素大约占50%。男性不育病因复杂多样,很多目前尚不能明确。近年来,RNA结合蛋白在男性不育中的作用引起人们的关注。反式激活应答DNA/RNA结合蛋白(TDP-43)是一种DNA/RNA结合蛋白,参与睾丸组织中的基因调控,其异常表达可影响男性生育能力,导致男性不育。TDP-43在正常精子与异常精子中的分布与表达量也是不同的,可能是一种男性不育的标志物。本文主要就TDP-43的结构及其在男性不育中的作用进行综述。

反式激活应答元件RNA在HIV-1感染中的作用

反式激活应答(transactivation response,TAR)元件RNA作为HIV-1中的一种非编码RNA,从转录与翻译水平负调控HIV-1的基因表达.同时HIV-1采取了相应的策略拮抗TAR RNA的负调控作用:病毒蛋白Tat或细胞蛋白TAR RNA结合蛋白(TRBP)结合TAR RNA后,分别在转录与翻译水平促进HIV-1的基因表达.此外,TAR编码的miRNA有助于保持HIV的潜伏感染及阻止细胞凋亡.TAR与其它蛋白间相互作用及其功能的研究对于深入了解HIV-1感染细胞后的调控机制,寻求新的抗HIV治疗靶点具有重要意义.

补肾活血中药龙鳖制剂干预野生型TDP43介导的骨性关节炎软骨细胞病变的作用研究

目的：分析补肾活血中药龙鳖对TDP-43引起骨性关节炎应急反应的软骨细胞病变的干预作用。方法：通过构建TDP43慢病毒载体并转染人软骨细胞,流式细胞检测分析凋亡水平,连续细胞计数分析其细胞增殖水平,荧光定量PCR检测关键基因表达水平;采用软骨细胞培养液中加入低、中、高剂量龙鳖进行干预,分析TDP43慢病毒转染软骨细胞后的凋亡和增殖生长水平。结果：人软骨细胞转染包装好的TDP43慢病毒后,高表达TDP43基因和I型胶原蛋白α1。TDP43慢病毒转染的软骨细胞体外连续培养软骨细胞7 d后,软骨细胞出现晚期凋亡和死亡现象而抑制了细胞增殖。龙鳖加入培养后软骨细胞呈生长趋势,TDP43慢病毒转染的软骨细胞凋亡显著下降而显著提高了其增殖水平。结论：转染TDP43慢病毒软骨细胞表达TDP43引起了细胞凋亡和抑制其增殖,TDP43可能在骨性关节炎发病过程中取到负调控的作用,而中药龙鳖制剂可显著改善这一过程。

骨桥蛋白对骨关节炎软骨细胞缺氧诱导因子-2α mRNA表达的影响

[目的]本研究探讨在体外实验中，骨桥蛋白（OPN）对缺氧诱导因子-2α（HIF-2α）在软骨细胞表达的影响，揭示OPN在骨关节炎（OA）发病中的作用机制。[方法]从OA患者胫骨表面切取软骨，并在体外培养纯化软骨细胞。用重组人类骨桥蛋白（rhOPN组）和小干扰RNA（siRNA组）对软骨细胞进行干预（对照组不予激活及干预），检测HIF-2αmRNA表达的变化。用抗-CD44单克隆抗体检测可能的配体-受体的相互作用。通过实时定量聚合酶链反应（RT-PCR）同时定量软骨细胞OPNmRNA和HIF-2αmRNA的表达。[结果]rhOPN组与对照组相比，HIF-2αmRNA的表达水平显著降低，相反，siRNA组HIF-2αmRNA表达增加。同时，CD44抗体可以抑制0PN对HIF-2αmRNA的表达的影响。[结论]OPN可能通过CD44的相互作用，抑制0A软骨细胞HIF-2αmRNA的表达，从而发挥对0A的保护性作用。

大鼠Mecp_2基因的RNA干扰有效序列筛选

目的：以RNAi技术寻找抑制大鼠Mecp2基因表达的有效序列。方法：首先构建大鼠Mecp2基因与红色荧光蛋白（RFP）的融合基因表达质粒，然后分别与针对大鼠Mecp2基因的4个备选小干扰RNA（siRNA，small interference RNA）共转染HEK293T细胞，构成外源基因系统，以此对于4个备选的siRNA对大鼠Mecp2基因的抑制有效性进行筛选。然后将筛选到的有效序列siRNA转染自身表达大鼠Mecp2基因的PC12细胞，以免疫荧光染色显示大鼠Mecp2蛋白的表达情况，通过内源大鼠Mecp2基因表达被抑制的情况验证所筛选序列的RNA干扰有效性。结果：针对大鼠Mecp2基因mRNA918—936位核苷酸的siRNA（序列：5＇-GCUGUGAAGGAAUCUUCUA-3’）是对大鼠Mecp2基因进行RNA干扰的有效序列。此有效siRNA序列所在的位置相当于大鼠Mecp2基因第4外显子，推测可同时抑制大鼠Mecp2α和大鼠Mecp2β的表达。且此靶序列位于大鼠Mecp2基因编码区，推测可同时抑制1．9kb和10kh的大鼠Mecp2基因mRNA的表达。结论：本研究为建立稳定的大鼠神经元Mecp2基因表达敲低的神经细胞模型和研究脑发育过程中Mecp2基因的功能打下了基础。

肌萎缩侧索硬化患者血浆TDP-43含量及与病程关系的研究

目的检测肌萎缩侧索硬化(ALS)患者与健康人血浆中TAR DNA结合蛋白43(TDP-43)水平,探讨血浆TDP-43浓度变化与ALS病程之间的关系。方法收集散发性ALS患者和健康人血浆,利用ELISA法测定血浆中TDP-43浓度,使用SPSS软件进行统计学分析。结果散发性ALS患者血浆中TDP-43浓度显著高于健康人,随着病程的进展,血浆中TDP-43浓度没有明显的变化。结论 TDP-43是散发ALS的一个重要生化指标,其在ALS患者血浆中含量增加,但与疾病病程无关。

利美尼定促进肌萎缩侧索硬化相关蛋白质TDP-43降解的研究

目的探索利美尼定(RIL)对肌萎缩侧索硬化(ALS)相关蛋白质TAR DNA结合蛋白43(TDP-43)降解的影响.方法用瞬时转染的方法在运动神经元样细胞系NSC-34中过表达WT TDP-43,与家族型ALS相关的Q331K TDP-43、M337V TDP-43突变蛋白、TDP-43的两种C末端片段TDP-25和TDP-35,再给予利美尼定干预16h,通过蛋白印迹方法检测5种TDP-43的表达水平.结果在自噬诱导剂RIL的作用下,两种突变TDP-43及其C末端片段的表达明显减少,而WT TDP-43的蛋白质表达水平无明显变化.在自噬阻断剂3-MA的干预下,RIL降解异常蛋白质的作用也被阻断.结论RIL可经由自噬通路降解Q331K TDP-43、M337V TDP-43及其C末端截短片段.