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作者首先简述了Bcl-2蛋白家族成员Bcl-xL蛋白的结构与功能,Bcl-xL蛋白是体内重要的抗凋亡蛋白,其头部折叠结构完全符合Bcl-2家族蛋白结构模型,对多种细胞具有保护作用;其次介绍了Bcl-xL蛋白的功能增强型突变体PTD-FNK蛋白的生物学特性、功能、作用机制及临床应用情况,其对体内外细胞的穿透能力很强,可能通过抑制细胞线粒体途径的凋亡对不同类型细胞受到的多种损伤刺激产生良好的防御作用,这种组织细胞保护作用目前已经在临床治疗上被广泛应用。目前两种蛋白批量生产及实践应用的难点是其原核表达形式为包涵体,需要经过复杂的复性过程才能获取可溶性蛋白,且蛋白在复性过程中损耗极大。通过探索诱导两种蛋白表达的最优条件,大量诱导蛋白的可溶性表达并且进行纯化是今后研究工作的重点和方向,可为更好地推进其在组织细胞常温、低温、冷冻保存及医学临床中的应用奠定基础。  相似文献   

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[目的] 探究PTD-FNK蛋白对雄性小鼠生理功能的影响。[方法] 将16只8周龄健康雄性C57BL/6J小鼠随机分为对照组(n=8)和PTD-FNK蛋白组(n=8),对照组腹腔注射生理盐水,PTD-FNK蛋白组腹腔注射300 μg/(kg·BW)PTD-FNK蛋白,每天腹腔注射给药1次,连续给药7 d;给药期间每天记录小鼠的体重、体温、血糖、采食量、饮水量,计算试验期间总采食量、总饮水量、体增重;于试验第1天和最后1天测量鼻肛距,计算试验前后Lee's指数;试验结束立即处死小鼠,称量心脏、肾脏、肝脏、脾脏和睾丸重量,计算脏器指数;分离小鼠附睾,制备精子悬液,测定精子活力和质膜完整率;利用qPCR法检测睾丸组织中细胞凋亡相关基因BaxCaspase-3、氧化应激相关基因SODGPX1、内分泌相关基因STAR、17β-HSD的mRNA相对表达量。[结果] 与对照组相比,PTD-FNK蛋白组小鼠总采食量极显著(P<0.001)下降,总饮水量显著(P<0.05)下降;Lee's指数、体温、体重、血糖无显著(P>0.05)变化。肝脏指数显著(P<0.05)下降,其他脏器指数无显著(P>0.05)变化。精子活力极显著(P<0.01)升高,精子质膜完整率无显著(P>0.05)变化。睾丸组织中Bax基因mRNA相对表达量极显著(P<0.01)升高,Caspase-3基因mRNA相对表达量无显著(P>0.05)变化,SOD基因mRNA相对表达量极显著(P<0.01)升高,GPX1基因mRNA相对表达量无显著(P>0.05)变化,17β-HSDSTAR基因的mRNA相对表达量无显著(P>0.05)变化。[结论] PTD-FNK蛋白可以抑制雄性小鼠的采食、饮水及肝脏的生长发育,提高小鼠的精子质量。  相似文献   

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细胞凋亡是由多基因控制的细胞自主有序的死亡,以维持内环境稳定。其在多细胞生物的组织分化、器官发育、机体稳态的维持中有重要意义。细胞凋亡可促进因感染、损伤所致的细胞死亡并被机体清除,临床上细胞凋亡与许多疾病有直接关系。B细胞淋巴瘤-2(Bcl-2)家族蛋白是参与细胞凋亡的重要调节分子,既可抑制也可促进细胞凋亡。作者概述了Bcl-2蛋白家族成员、结构特点、Bcl-2蛋白家族与细胞凋亡的关系及生物学意义。  相似文献   

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为研究断喙应激对雏鸡胸腺细胞凋亡及相关凋亡蛋白表达的影响,采用电子显微镜技术、流式细胞术和免疫组织化学技术分析断喙对鸡胸腺淋巴细胞的细胞增殖、分化、凋亡及相关凋亡蛋白(Bcl-2和Bax)表达的影响.结果表明:采用电子显微镜技术观察到断喙对胸腺淋巴细胞产生明显的影响,断喙组胸腺细胞内可看到细胞核明显的应激反应,细胞核凝集,较致密,部分细胞核即将溶解,并出现一定数量的凋亡和坏死细胞;流式细胞仪检测表明对照组和断喙组的胸腺内淋巴细胞都是以G1期为主,但断喙组G1期淋巴细胞数量比试验组高;对照组和断喙组胸腺淋巴细胞凋亡率在断喙后5d时差异显著(P<0.05);免疫组化结果表明断喙应激没有影响Bcl-2和Bax蛋白在免疫器官内的表达部位;但有降低Bcl 2在胸腺细胞内表达量的趋势;有提高Bax在胸腺细胞内表达量的趋势.结果表明断喙应激促进了雏鸡胸腺淋巴细胞凋亡.  相似文献   

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This review focuses on the pro-apoptotic and anti-apoptotic Bcl-2 family members involved in apoptosis, which is the predominant process controlling cell remodelling during post-lactational mammary gland involution. The members of the Bcl-2 protein family, whose expression levels are under the control of lactogenic hormones, internally control this mechanism also during lactation. They can physically interact with each other, sometimes in an antagonistic manner. Mammary glands undergo repeated cycles of structural development, functional differentiation and regression, therefore provide a unique model for investigating this family of proteins that regulate the fate of the secretory cells and consequently milk yield. The involvement of Bcl-2 family members is reviewed in mammary tissue during morphogenesis, at different stages of lactation cycle and in comparison with dairy and laboratory animals.  相似文献   

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The bcl-2 family of genes encodes proteins that influence apoptosis. In the present immunohistochemical study, the topographic distribution of bcl-2 protein was examined in healthy feline fetal, neonatal, and adult tissues, a feline renal cell line, and feline tumors obtained from a veterinary hospital. The topographic distribution of bcl-2 in healthy tissues was similar to that described in human tissues. In lymphoid tissues, follicular mantle cells strongly expressed bcl-2. In complex and differentiating epithelium, bcl-2 expression was detected in stem cell and proliferation zones. Bcl-2 expression was also detected in lower crypts of the intestine and in skin basal layers. The feline Crandell kidney cells expressed bcl-2 diffusely throughout the cytoplasm. Of 180 tumors examined, bcl-2 was expressed almost uniformly in cutaneous basal cell tumors, thyroid adenomas, and mammary carcinomas and in 50% of the lymphomas examined. Bcl-2 may play a role in blocking apoptotic cell death in a broad range of normal feline tissues, whereas dysregulated bcl-2 may extend the life of certain tumors or render certain tumors resistant to therapy because most chemotherapeutic and radiotherapeutic agents eliminate tumor cells by triggering apoptosis.  相似文献   

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Expression of Bcl-2 in feline lymphoma cell lines   总被引:1,自引:0,他引:1  
BACKGROUND: The Bcl-2 gene is a member of the rapidly expanding Bcl-2 family of genes that regulate apoptosis. Bcl-2 has been shown to repress cell death triggered by a diverse array of stimuli, including chemotherapy and gamma irradiation. OBJECTIVE: The purpose of this study was to determine feline Bcl-2 expression level in feline lymphoma cells using an immunoblot assay with anti-human and anti-canine Bcl-2 monoclonal antibodies. METHODS: About 708 base pairs containing the coding sequence of the feline Bcl-2 gene were transformed into Escherichia coli. The recombinant Bcl-2 was used as a positive control for an immunoblot assay using mouse monoclonal antibodies against human and canine Bcl-2. An immunoblot assay using the monoclonal antibodies was carried out to determine the level of feline Bcl-2 expression in lymphoma and lymphocytic leukemia cell lines. RESULTS: The recombinant feline Bcl-2 protein produced in E. coli had a molecular weight of about 26 kDa and was detected by immunoblot assay by using anti-human Bcl-2 mouse monoclonal antibody. Feline Bcl-2 expression was high in lymphoma cell lines (FL-74-UDC-1 and FT-1) and low in the cell line from peripheral blood mononuclear cells from a healthy cat (FeTJ-1) but not low in freshly isolated peripheral blood mononuclear cells from a healthy cat. The anti-human Bcl-2 mouse monoclonal antibody was found to cross-react with feline Bcl-2. CONCLUSIONS: These results confirm the expression of Bcl-2 in T-cell lymphoma cell lines and indicate that it is suitable to detect feline Bcl-2 using an immunoblot assay. Pending further evaluation, Bcl-2 expression might be useful in the differential diagnosis of feline tumors.  相似文献   

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本试验应用光镜、电镜、流式细胞术、实时定量PCR技术研究了雌激素诱导小鼠胸腺萎缩过程中胸腺指数、胸腺显微和超微结构、胸腺细胞凋亡率及部分细胞因子和凋亡相关蛋白基因表达的变化。结果注射雌激素后,小鼠胸腺指数显著下降,胸腺中凋亡细胞数量显著上升,细胞因子TGF-β1表达量显著升高,IL-6表达量略为升高,而IL-7表达量显著降低;凋亡相关蛋白Caspase-3、Caspase-9、FADD表达量显著上升,FasL表达量略有上升,而Bcl-2表达量显著降低。表明雌激素可能一方面通过调节胸腺细胞因子抑制胸腺上皮细胞的增殖,另一方面通过激活Caspase级联程序的启动和执行阶段及Fas/FasL凋亡信号通路促进胸腺细胞的凋亡,从而诱导小鼠胸腺萎缩。  相似文献   

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业已明确家蚕30K蛋白不仅作为家蚕生长发育的重要能源物质,还对细胞凋亡具有明显的抑制作用。采用RT-PCR技术从家蚕5龄幼虫脂肪体中克隆了BmLp-C6、BmLip19G1和BmLp-C12p(GenBank登录号分别为X54735、AY568957、NM_001101728)共3种30K蛋白基因的cDNA序列,并利用Bac-to-Bac系统构建含有3种30K蛋白基因的重组杆状病毒表达载体,转染家蚕BmN培养细胞大量表达3种30K蛋白,3种表达产物纯化后的样品经SDS-PAGE检测到明显的30 kD大小的目的蛋白条带,Western blotting分析3种纯化后的蛋白样品与6×His-tag抗体具有良好的特异性反应。纯化后检测3种表达产物对诱导凋亡的抑制作用。经MTT法检测3种纯化30 K蛋白可明显增强过氧化处理的人血管内皮原代培养细胞(EC)的活力,采用ELISA法检测3种纯化30K蛋白能明显减缓EC细胞中的DNA片段化,显示3种30K蛋白对H2O2诱导的EC细胞的凋亡均具有一定的抑制作用。用生物信息学方法预测3种家蚕30K蛋白的氨基酸序列相似性达43%,三级结构极其相似,推测3种蛋白具有相似的生物学功能。  相似文献   

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The placenta produces various peptides and steroid hormones that regulate placental function and fetal growth. Prolactin‐related proteins are peptides that are produced by the placenta and belong to the growth hormone/prolactin family, and have structural similarity to prolactin and placental lactogen. Although several prolactin‐related protein genes have been detected in bovine placenta, their expression profiles and functions are not clear. The main difficulties in examining their biological function is the similarity between their genes and the lack of information about their proteins. Recently, molecular biology methods have been used to detect some new bovine prolactin‐related proteins, and elucidate their biological functions. This review focuses on the structures, expression profiles and conceivable functions of prolactin‐related proteins in bovine placenta. With respect to their expression profiles, bovine prolactin‐related proteins fall into four groups: (i) those expressed around the implantation period; (ii) those that reach peak expression in the middle of gestation; (iii) those that increase with the progress of gestation, reaching a peak in late gestation; and (iv) those that reach a plateau in early gestation and are maintained at that level throughout gestation. Data indicate that bovine prolactin‐related proteins have different biological roles in different periods of gestation. In situ monitoring suggests that bovine prolactin‐related protein‐I has a role in the attachment of trophoblast cells to endometrium during the early implantation period.  相似文献   

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Bcl-2 and Bax proteins localised mainly in granulosa cells. Primordial and primary follicles of new born rat ovary showed an intensive nuclear staining for Bax but faint staining for Bcl-2. In terms of staining intensity, no remarkable difference was observed within the same stage of developing follicle. Compared to new born rats, granulosa cells of adult and one month old rat ovary showed an increased staining both for Bcl-2 and Bax proteins. No staining was observed in primordial follicles of one month old and adult rats. However, granulosa cells of primary follicles, granulosa cells and theca cells in tertiary follicles of adult rat ovary also showed a strong staining for Bcl-2 and Bax proteins. Oocytes of follicles from different developmental stages revealed an apparent staining both for Bcl-2 and Bax proteins. However, in the more mature follicles oocytes stained more intensively. In developing corpus luteum a remarkable staining was observed for Bax. However, the staining was more prominent in regressing corpus luteum. Contrary to this, Bcl-2 stained the luteal cells in developing corpus luteum strongly, while in the fully developed corpus luteum no staining for Bcl-2 was observed. In conclusion, there was an apparent relation between the expression of the apoptosis regulating protein Bcl-2 and Bax and follicular development. Thus, during the follicular development Bcl-2 and Bax may be involved in granulosa cell demise in rat ovary. Furthermore, increased levels of Bax and decreased levels of Bcl-2 in the fully developed corpus luteum suggest that Bax plays a role in apoptosis of luteal cells in rat ovary.  相似文献   

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ObjectivesTo determine the percentage of cells undergoing apoptosis within canine myxomatous valves and to evaluate whether TGFβ1 can be implicated as an anti-apoptosic signal through the Bcl-2 family of signaling proteins.AnimalsPost-mortem mitral valve leaflets harvested from 5 normal dogs, 5 dogs with early-stage myxomatous mitral valve disease (MMVD), and 5 dogs with late-stage MMVD.Materials and methodsThe number of cells expressing cleaved caspase-3, DNA fragmentation (TUNEL marker) and apoptotic bodies were evaluated as a measure of apoptosis. To evaluate the relationship between TGFβ1 signaling and apoptosis, the abundance of activated TGFβ1 signaling protein, phosphorylated Smad 2/3 (p-Smad 2/3), and Bcl-2 family proteins (pro-apoptotic Bax and anti-apoptotic Bcl-2) was determined by immunohistochemistry.ResultsCells in normal and both stages of MMVD expressed the TUNEL marker and cleaved caspase-3, but not apoptotic bodies. The percentage of TUNEL marker and cleaved caspase-3 positive nuclei was not significantly different between groups of dogs (p > 0.05). P-Smad 2/3 and Bax were more abundant in myxomatous mitral valves while Bcl-2 was less abundant. P-Smad 2/3 primarily increased in the atrialis layer and was abundantly increased only in late-stage MMVD.ConclusionsThese data suggest that interstitial cells in MMVD are in a pro-apoptotic condition; however, they do not execute apoptosis. Thus, apoptosis does not explain differences in cellular density in canine MMVD. TGFβ1 signaling through the canonical SMAD pathway is increased in myxomatous mitral valves, but does not apparently mediate interstitial cell apoptosis in canine MMVD.  相似文献   

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为提高鸡IFN-γ基因重组蛋白的复性效率,用18种不同的复性缓冲液对在大肠埃希菌中表达的cIFN-γ进行复性处理,通过SDS-PAGE分析、考马斯亮蓝定量、对鸡胚成纤维细胞以及对鸡胚的保护试验检测复性产物的得率和生物学活性.结果表明,去污剂和疏水剂能保证蛋白的复性得率和复性效率,重组表达产物得率可高达94.7%;氧化还...  相似文献   

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冬季持续低温引起的冷应激是降低北方畜牧业经济效益和动物福利的重要因素,可诱导动物产生炎症反应和氧化应激危害机体健康。热休克蛋白作为体内重要的分子伴侣蛋白,在维持机体内环境稳态、帮助动物抵抗应激方面有重要作用,低温环境可激活热休克蛋白快速产生,以此在细胞内外对免疫和抗氧化系统发挥重要调节作用:在胞外,具有保护细胞、参与调节免疫细胞功能、激发免疫反应和提高抗氧化酶活性等作用;在胞内,可抑制NF-κB信号通路保护机体免受炎症损伤,上调Nrf2信号通路提高机体抗氧化功能,缓解冷应激对机体造成的负面影响。本文总结了国内外关于在冷应激状态下热休克蛋白对机体免疫和抗氧化功能的调节作用及其机制,并给出部分提高热休克蛋白表达水平的方法,以期为后续畜禽的冷应激理论研究提供参考。  相似文献   

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Previous studies have shown that four and a half LIM domain protein 2 (FHL2) plays an essential role in the regulation of follicular development in mammals. Although the FHL2 genes of human and mouse have been well characterized, the expression and location of FHL2 in ovary and the biological functions of FHL2 on granulosa cells (GCs) of ovine are still not clear. In this study, full-length complementary DNA (cDNA) of FHL2 from ovine follicular GCs was amplified by real-time PCR (RT-PCR). The expression and location of FHL2 in ovary and GCs of ovine were studied by immunohistochemistry and immunofluorescence, and the biological effects of FHL2 on the cell proliferation, cell apoptosis, cell cycles and expression level of related genes of ovine GCs were also explored by overexpression or knockdown of FHL2. The results indicated that FHL2 was expressed in ovine follicular GCs and the sequence of the FHL2 cDNA was consistent with that predicted in GenBank, which did not cause an amino acid change. According to the results, FHL2 was expressed in ovine ovary and mainly located in the cytoplasm and nucleus of GCs. In addition, overexpression of FHL2 significantly reduced the cell viability, promoted the cell apoptosis and decreased the percentage of G0/G1 and S phase cells. RT-PCR showed that overexpression of FHL2 significantly increased the mRNA expression level of Bax and decreased the expression of Bcl-2 and the Bcl-2/Bax mRNA ratio compared with the control group. Besides, the knockdown of FHL2 gene in ovine GCs significantly improved the cell viability, suppressed the cell apoptosis, decreased the mRNA expression level of Caspase-3 gene, increased the Bcl-2/Bax mRNA ratio and increased the percentage of S and G2/M phase cells. Our results suggest that FHL2 may play an important role in the biological functions of GCs in ovine.  相似文献   

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应用光镜和实时定量PCR技术研究了Ghrelin对雌激素诱导小鼠胸腺萎缩过程中胸腺形态学以及部分细胞因子和凋亡相关蛋白基因表达的影响。结果显示,注射Ghrelin后,雌激素诱导的小鼠萎缩胸腺在形态学上基本恢复到正常水平,胸腺中IL-6、TGF-[31、Caspase3、FADDmRNA含量显著降低,Caspase9、FasLmRNA含量略为下降,而IL-7、Bcl-2mRNA含量有所上升。结果表明,Ghrelin可能通过促进胸腺上皮细胞的增殖以及阻断Caspase级联程序和Fas/FasL凋亡信号通路抑制胸腺细胞的凋亡,从而逆转雌激素诱导的小鼠胸腺萎缩。  相似文献   

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外泌体(exosome)是通过细胞内多泡体与细胞膜融合产生的纳米级细胞外膜泡,广泛分布在血清、尿液、唾液和其他生物液体中。外泌体作为细胞间通信和遗传物质的重要转移载体,可通过受体介导的相互作用或通过各种生物活性分子(如细胞膜受体、蛋白质、mRNA和miRNA)的转移直接刺激靶细胞,从而发挥其生物学功能。文章主要综述了外泌体内含蛋白质和miRNA的功能及外泌体在临床中的应用。外泌体内蛋白质和miRNA的功能包括生理状态下诱导机体免疫、递呈抗原、参与细胞间信号传导;病理状态下改变肿瘤微环境、促进癌细胞增殖、侵袭、加快血管生成、促进癌症发展;以及某些病毒可将其组分包装、整合到外泌体中来实现细胞间传播,或劫持外泌体,实现免疫逃避。作者主要介绍了其作为肺癌、乳腺癌、胰腺癌及结直肠癌等多种癌症早期诊断的生物性标志物,以及作为稳定性高、转运效率高、靶向性强的药物载体在临床中的应用。  相似文献   

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