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1.
磷酸酶(ACP、AKP)在生物的机能分化中起重要作用,热休克蛋白(HSPs)是近几年发现的一类在胚胎发育、细胞生存中起重要作用的分子,无论是胚胎发育还是细胞结构和功能构建都和细胞增殖密切相关,增殖细胞核抗原(PCNA)是检测细胞增殖的良好指标。 本实验用组织化学、免疫组织化学、Western印迹、酶的原位复性电泳、体视学分析等方法定性和定量分析了酸性磷酸酶(ACP)(Fig.1&2)、碱性磷酸酶(AKP)(Fig.4&5)、构成性热休克蛋白 70/诱导性热休克蛋白 68(HSC70/HSP68)(Fig.6)和PCNA(Fig.7&8, Table1)在大鼠肝生长发育(从14天胚胎到成体)过程中的动态变化。结果表明:(1)在大鼠肝生长发育过程中,ACP有两个活性高峰期,其时段处于大鼠吃奶和吃饲料起始期(Fig.1&2);(2)在ACP的第一个活性高峰期时,AKP活性降低;而在ACP的第二个活性高峰期时,正值AKP的活性高峰期(Fig.3);(3)ACP活性高峰期也是PCNA含量高峰期;(4)HSC70/HSP68在刚断奶的幼鼠肝和成体肝中表达量较多,其他时段表达极少。根据上述结果推测:ACP和PCNA通过调节细  相似文献   

2.
C6大白鼠神经胶质瘤细胞HSP68的修饰和降解分析   总被引:7,自引:0,他引:7  
本文用蛋白水解酶复性电泳、放射自显影和Western印迹等方法分析C6细胞HSP68在体内、外修饰和降解表明:(1)C6细胞的中性蛋白水解酶几乎不参与HSP68降解;(2)HSP68降解涉及到胞液ATP结合蛋白水解酶和溶酶体酸性蛋白水解酶,其中,ATP结合蛋白水解酶在起动HSP68降解和把HSP68降解成多肽大片段方面起重要作用,溶酶体酸性蛋白水解酶主要参与把多肽大片段彻底降解;(3)热休克诱导H  相似文献   

3.
四氯化碳所致肝硬化的大白鼠,进行70%和30%肝脏切除,于术后48小时、1周、2周分别取剩余肝脏观察肝的组织化学变化,包括DNA(脱氧核糖核酸),histone(组蛋白)、RNA(核糖核酸)、SDH(琥珀酸脱氢酶)、G-6-Pase(葡萄糖-6-磷酸酶)、Mg-ATPase(镁激活三磷酸腺苷酶)、ChE(胆碱酯酶)、AKP(碱性磷酸酶)、ACP(酸性磷酸酶),PAS(糖原)反应。其中肝硬化切除30%肝脏的动物,术后48小时再生肝细胞活跃,肝脏DNA、histone、SDH、G-6-pase、ATPase活性及反应明显增高;而ChE活性及PAS反应等显著减弱。  相似文献   

4.
酵母PHO85结合蛋白PAP1基因的克隆和表达   总被引:3,自引:3,他引:0  
酵母调探因了PHO85是一个依赖于细胞周期蛋白(cyclin)的蛋白酶(CDK),参与对细胞周期和酸性磷酸酯酶基因表达的调控。冯PHO85为靶分子,利用酵母的染色体基因文库中克隆到了一个新的与PHO85相结合的蛋白因子的基因,利用酵母双杂交(two-hybrid)系统从酵母的染色体基因文加中克隆到了一个新的与PHO85相结合的蛋白因子的基因,将此蛋白质命名为PAP1(PHO85associated  相似文献   

5.
三种蜘蛛丝蛋白组成分析   总被引:2,自引:0,他引:2  
谢锦云  陈平 《激光生物学报》1995,4(3):705-708,703
本文应用高压液相色谱(HPLC)法分析了岳麓山的大腹园蛛Araneus ventricosus(C.Koch,1878),机敏漏头蛛Agelena difficlis (Fox,1937),白额巨蟹蛛Heteropoda venatoria (Linnaeus,1757)的丝蛋白的氨基酸组成,以SDS-PAGE法测定了大腹园蛛不同丝腺体的未成丝的可溶性丝蛋白的分子量。实验结果表明蛛丝蛋白中占优势的  相似文献   

6.
用Kunkel突变法,将单链尿激酶型纤溶酶原激活剂(scu-PA)cDNA基因中编码Pro155—Lys158的片段定点突变,并将此突变的scu-PA(tscu-PA)的cDNA克隆到表达载体pCM-β-neo中,与pCM-dhfr共转染CHO/DHFR-细胞.获得的稳定表达株在无血清培养基中24h的表达量为620IU/106细胞.经锌离子螯合Sepharose亲和层析得到tscu-PA纯品.SDS-PAGE显示tscu-PA分子量为53kD左右,与预期的结果相符.tscu-PA是由凝血酶激活而不是由纤溶酶激活,但激活后也能转变为双链分子(tcu-PA).tscu-PA仍保持了scu-PA的血纤维蛋白亲和性.酶动力学研究表明,激活后的tscu-PA水解S2444的Km和Kcat值与高分子量尿激酶(HUK)相似.体外溶栓实验结果表明,tscu-PA可以选择性地溶解富含凝血酶的血凝块,对贫凝血酶的血凝块作用不大  相似文献   

7.
大鼠自发性高血压与HSP70基因关系的研究   总被引:2,自引:0,他引:2  
黄生宁  杨鸿 《生理学报》1994,46(3):288-292
本实验采用热休克蛋白70核酸分子杂交方法,检测了自发性高血压大鼠和正常血压大鼠离体培养的主动脉平滑肌细胞受热刺激后HSP70mRNA水平的变化以及整体动物肝组织HSP70mRNA的水平,并对肝组织基因组DNA进行了限制性酶切片段长度多态性分析。结果表明:37℃培养的SHR ASMC及整体SHR肝组织HSP70 mRNA的基础表达水平均低于WKY鼠,SHR ASMC受热刺激(42℃ 15min)后2  相似文献   

8.
动脉平滑肌细胞(sm ooth m uscle cell,SMC)是动脉粥样硬化(atherosclerosis,AS)斑块中的主要细胞,它的增殖在AS形成过程中极其重要.利用体外培养的人主动脉SMC,观察了天然高密度脂蛋白(native high density lipoprotein,N-HDL)及氧化修饰HDL(oxidized HDL,OX-HDL)对培养人主动脉SMC cyclin D1(细胞周期蛋白D1)基因转录表达的影响.结果表明:(1)N-HDL对SMCcyclin D1基因表达无影响(P> 0.05);(2)OX-HDL使SMCcyclin D1基因表达显著增强(P<0.01),其表达量随时间(2、12、24 h)延长而增加.上述结果表明,OX-HDL的致AS作用可能与其刺激SMCcyclin D1基因表达增加有关.  相似文献   

9.
测定了伴刀豆球蛋白(ConcanavalinA)和DIDS对人红细胞带3蛋白活性及结构的影响。(1)ConA使带3转运速度常数K显著增加。ConA浓度达到0.05mg/ml时,K值增加34.4%。DIDS对带3活性有明显的抑制作用。(2)荧光探针DPH,3AS,9AS,16AP分别测定ConA和DIDS与带3结合后膜流动性的变化。ConA能明显增加膜脂的流动性,而DIDS则降低膜脂流动性。(3)差示扫描量热法(DSC)测定带3蛋白变性性质,发现ConA使红细胞膜上带3蛋白变性峰出现温度从69.25°C减小到66.25°C,而DIDS则使之增至79.5°C。  相似文献   

10.
高产稳产聚羟基烷酸的重组大肠杆菌的构建   总被引:7,自引:0,他引:7  
重组大肠杆菌Escherichia coliHMS174(pTZ18UPHB) 含有携带聚羟基烷酸(PHA) 合成基因( phaCAB)** 的质粒pTZ18UPHB,是很有潜力的PHA 生产菌,但存在着质粒不稳定和不能合成3羟基丁酸(3HB) 与3羟基戊酸(3HV) 共聚物[P(3HBco3HV)] 的缺陷。将RK2 质粒上的par DE 基因引入pTZ18UPHB 构成质粒pJMC2 ,该质粒可以在宿主E.ColiHMS174 中稳定遗传。将培养基中的磷酸盐浓度降至18 m mol/L,发现E.Coli HMS174(pJMC2) 能够以丙酸为前体合成P(3HBco3HV) ,其中3HV 在共聚物中的含量为5 % ~8 % 。在5L自动发酵罐中分批补料培养E.Coli HMS174(pJMC2) ,培养基初始磷酸盐浓度为15 m mol/L,30 h 后每升培养液中干菌体可达42-5 g,P(3HBco3HV) 占干重的70 % ,其中3HV 在共聚物中的含量为4-9 % 。  相似文献   

11.
大鼠肝大部分切除前热休克对热休克蛋白和磷酸酶的影响   总被引:3,自引:1,他引:2  
The contribution and content of the continuous heat shock protein 70/induced heat shock protein 68 (HSC70/HSP68), the contribution, variety and activity of acid phosphatases (ACP) and alkaline phosphatases (AKP) had been analysed qualitatively and quantitatively during the liver regeneration after 2/3 hepatectomy (PH) and HS (heat shock at 46 degrees C for 30 min, recovery for 8 h), which were compared with the results only by HS and only by PH. It was shown that the three kinds of treatment all can increase the activity of ACP, AKP and the expression of HSC70/HSP68, but with different change pattern. A further analysis show that after HS-PH the enhanced activity of ACP is related with that of 140 kD phosphatases, the enhanced activity of AKP is associated with that of 140 kD and 160-180 kD phosphatases. It can be reckoned from the results that ACP, AKP and HSC70/HSP68 all act on the heat shock response of hepatocyte and liver regeneration, and may take part in signal transduction in these processes, but ACP may play a dominant role in the start of hepatocyte multiplication, AKP and HSC70/HSP68 may play a dominant role in cytokineses.  相似文献   

12.
In this paper, the models of 36-4-4 SISPH and 4-36-36-36 SISPH were used to analyze the changes of activity and content of ACP, AKP, HSC70/HSP68 and PCNA in rat liver. The results showed that the activities of 140 kD ACP and AKP in SISPH were increased following the increase of SISPH number of times, but that of 160 kD ACP and AKP were decreased following the increase of SISPH number of times. The content of PCNA in 4-36-36-36 SISPH were more than that in 36-4-4 SISPH, in contrast for HSC70/HSP68 in these two models. Therefore, the content and activities of ACP, AKP, HSC70/HSP68 and PCNA could be strongly effected by SISPH number of times and SISPH methods. Its mechanisms and physiological significance were discussed.  相似文献   

13.
Sumioka I  Matsura T  Kai M  Yamada K 《Life sciences》2004,74(20):2551-2561
The aim of the present study was to assess the contribution of the level of expression of heat shock protein 25 (HSP25), 60 (HSP60), 70 (HSC70) and 70i (HSP70i) in mouse livers after a lethal dose of acetaminophen (APAP) to their survival. We examined changes in survival ratio, plasma APAP level and alanine aminotransferase (ALT) activity, and hepatic reduced glutathione (GSH), HSP25, HSP60, HSC70 and HSP70i levels following treatment of mice with APAP (500 mg/kg, p.o.). The plasma APAP level increased rapidly, and reached a maximum 0.5 h after APAP treatment. Hepatic GSH decreased rapidly, and was almost completely depleted 1 h after APAP treatment. Plasma ALT activity, an index of liver injury, significantly increased from 3 h onwards after APAP treatment. The survival ratios 9 h, 24 h and 48 h after APAP treatment were 96%, 38% and 36%, respectively. We found a remarkable difference in the patterns of hepatic HSP25 and HSP70i induction in mice that survived after APAP treatment. HSP70i levels increased from 1 h onwards after APAP treatment in a time-dependent manner, and reached a maximum at 9 h. In contrast, HSP25 could be detected just 24 h after APAP treatment, and maximal accumulation was observed at 48 h. Other HSPs examined were unchanged. Notably, the survival ratio dropped by only 2% after HSP25 expression. Recently, a novel role for HSP25 as an anti-inflammatory factor was suggested. We have already shown that 48-h treatment with APAP induces severe centrilobular necrosis with inflammatory cell infiltration in mouse livers. Taken together, the level of expression of hepatic HSP25 may be a crucial determinant of the fate of mice exposed to APAP insult.  相似文献   

14.
Huang HC  Liu YC  Liu SH  Tzang BS  Lee WC 《Life sciences》2002,70(15):1763-1775
As widely believed treating cells with trichostatin A (TSA), an inhibitor of histone deacetylase, results in histone H4 hyperacetylation and cell cycle arrest. This compound is often compared with other potential anticancer drugs in cell cycle, proliferation and differentiation research. Furthermore, geldanamycin (GA), a 90-kDa heat shock protein (HSP90) specific inhibitor, is a well-known potential anticancer agent. This study examines whether GA can affect the cellular functions induced by TSA. When using TSA treatment, although caused COS-7 cell death, pretreatment of 0.5 microg/ml GA for 30 min and an addition of 50 ng/ml TSA (GA + TSA) apparently averted cell death. Our results indicated that the cell survival rate was only approximately 20% when prolonged treatment was undertaken with 50 ng/ml TSA (TSA) alone for 24 h. In contrast, the cell survival rate was enhanced by two folds when treating with GA + TSA. Furthermore, DNA fragmentation assay revealed that fragmented DNA was produced 8 h after prolonged treatment with TSA alone. Within 16 h, the apoptotic percentages of TSA-treated cells were between 15-25%. In contrast, the other treatments did not exceed 6%. Furthermore, GA inhibited TSA-induced histone H4 hyperacetylation. Western blotting analysis further demonstrated that the HSP70 levels did not significantly increase in TSA-treated cells. However, the accumulated 70-kDa heat shock protein (HSP70) markedly increased up to 2 to 3 folds at 8 h in GA- and GA + TSA-treated cells, and the maximum amount up to 5 to 7 folds at 20 h. Conversely, HSP90 did not markedly increase in all treatments. Based on the results in this study, we suggest that apoptosis induced by TSA can be prevented by GA-induced increment of heat shock proteins, particularly HSP70.  相似文献   

15.
35S-Met标记玉米胚蛋白合成结果表明,热激处理(42℃)与对照(25℃)的蛋白合成趋势相近,热激抑制16 DAP的蛋白合成,增加22和34 DAP蛋白合成.SDS-PAGE自显影图谱表明,热激诱导16DAP的胚合成86.4、80.0、73.2 kD等3种分子量较高的热激蛋白,22DAP后热激诱导合成86.4、80.0、73.2、24.4、18.2、16.8和13.6 kD等7种分子量的热激蛋白.2D-PAGE自显影图谱进一步显示,热激诱导22和28 DAP的胚合成近20种热激蛋白,其中超过10种为小分子热激蛋白.特异热激蛋白BiP(HsP70)、PDI(HsP60)Western blot表明,这2种热激蛋白在玉米胚发育过程均有高水平的表达,热激对其合成影响不明显.  相似文献   

16.
Heat shock protects HCT116 and H460 cells from TRAIL-induced apoptosis   总被引:5,自引:0,他引:5  
Heat shock proteins have been shown to protect cells from a variety of stressful conditions, including hyperthermia, oxidative and DNA damage, serum withdrawal, and a variety of chemicals. HSP27, HSP70, and HSP90 have been shown to downregulate different aspects of apoptosome assembly. TRAIL is a member of the TNF family of ligands and is a promising anti-cancer agent. It has been shown to be nontoxic to most normal cell types, while it is a potent killer of many different cancer cells. TRAIL engages both the receptor-mediated (extrinsic) and the mitochondria-initiated (intrinsic) cascades. We tested whether heat shock affects TRAIL-induced apoptosis in different cancer cells. TRAIL treatment does not induce HSP27, HSP70, or HSP90 levels. Nonetheless, when treated with TRAIL for 3 h after release from heat shock, the human colon cancer cell line HCT116 is protected from apoptosis whereas the human colon cancer cell line SW480 is not. This pattern is consistent with the previously observed behavior of HCT116 as Type II cells that depend on mitochondrial signaling and SW480 as Type I, whose TRAIL-induced death is not sensitive to inhibition of caspase 9. Moreover, the failure of heat shock to protect SW480 cells is not due to a lack of HSP70 or HSP90 upregulation. HSP70 and HSP90 are induced 3 h after release from heat shock, whereas HSP27 is induced much later. Thus, the observed protective effect against TRAIL is probably due to the anti-apoptotic effects of HSP70 and HSP90. These results further illustrate interactions between TRAIL receptor signaling and the intrinsic cell death pathway and have practical implications for the potential use of TRAIL and hyperthermia in cancer therapy.  相似文献   

17.
HSPs (heat shock proteins) have been recognized to maintain cellular homoeostasis during changes in microenvironment. The present study aimed to investigate the HSPs expression pattern in hierarchical neural differentiation stages from mouse embryonal carcinoma stem cells (P19) and its role in heat stressed exposed cells. For induction of HSPs, cells were heated at 42°C for 30 min and recovered at 37°C in different time points. For neural differentiation, EBs (embryoid bodies) were formed by plating P19 cells in bacterial dishes in the presence of 1 mM RA (retinoic acid) and 5% FBS (fetal bovine serum). Then, on the sixth day, EBs were trypsinized and plated in differentiation medium containing neurobasal medium, B27, N2 and 5% FBS and for an extra 4 days. The expression of HSPs and neural cell markers were evaluated by Western blot, flow cytometry and immunocytochemistry in different stages. Our results indicate that HSC (heat shock constant)70 and HSP60 expressions decreased following RA treatment, EB formation and in mature neural cells derived from heat-stressed single cells and not heat-treated EBs. While the level of HSP90 increased six times following maturation process, HSP25 was expressed constantly during neural differentiation; however, its level was enhanced with heat stress. Accordingly, heat shock 12 h before the initiation of differentiation did not affect the expression of neuroectodermal and neural markers, nestin and β-tubulin III, respectively. However, both markers increased when heat shock was induced after treatment and when EBs were formed. In conclusion, our results raise the possibility that HSPs could regulate cell differentiation and proliferation under both physiological and pathological conditions.  相似文献   

18.
The HSPs (heat‐shock proteins) of the 70‐kDa family, the constitutively expressed HSC70 (cognate 70‐kDa heat‐shock protein) and the stress‐inducible HSP70 (stress‐inducible 70‐kDa heat‐shock protein), have been reported to be actively secreted by various cell types. The mechanisms of the release of these HSPs are obscure, since they possess no consensus secretory signal sequence. We showed that baby hamster kidney (BHK‐21) cells released HSP70 and HSC70 in a serum‐free medium and that this process was the result of an active secretion of HSPs rather than the non‐specific release of the proteins due to cell death. It was found that the secretion of HSP70 and HSC70 is independent of de novo protein synthesis. BFA (Brefeldin A) did not inhibit the basal secretion of HSPs, indicating that the secretion of HSP70 and HSC70 from cells occurs by a non‐classical pathway. Exosomes did not contribute to the secretion of HSP70 and HSC70 by cells. MBC (methyl‐β‐cyclodextrin), a substance that disrupts the lipid raft organization, considerably reduced the secretion of both HSPs, indicating that lipid rafts are involved in the secretion of HSP70 and HSC70 by BHK‐21 cells. The results suggest that HSP70 and HSC70 are actively secreted by BHK‐21 cells in a serum‐free medium through a non‐classical pathway in which lipid rafts play an important role.  相似文献   

19.
Heat shock protein 70s (HSP70s) are fundamental chaperone proteins that are indispensable to most living organisms. In order to investigate the function of HSP70 and heat shock response in shrimp, a heat shock cognate (HSC70) gene of the white shrimp (Litopenaeus vannamei), containing a 1959-bp open reading frame, was cloned and characterized. The amino acid sequence, 71.5 kDa of molecular weight, shares 80–99.6% homology with 12 diverse species’ HSP70s and HSC70s. In fact, some segments of the eukaryotic HSC70 sequence, such as ATP/GTP-binding site, cytoplasmic HSP70 C-terminal sequence, and GGMP/GAP repeats, are also found in the putative shrimp HSC70. Moreover, multitissue RT-PCR was performed to assay the basal expressions of HSC70 in the heart, gill, hepatopancreas, stomach, gut, and muscle. The results demonstrate that the basal expressions of HSC70 in theses organs are similar to that of β-actin. Furthermore, quantitative real-time experiments showed that HSC70 was upregulated in hepatopancreas (4.6-fold), stomach (5.9-fold), gut (2.6-fold), and muscle (3.5-fold) but not in the heart (1.7-fold) and gill (1.6-fold) after 2 h of heat shock. Nevertheless, the HSC70 was found to be highly expressed in the heart and gill following 6 h of heat shock. This suggests that HSC70 in white shrimp possess both short-term and long-term responses to heat shock stress, indicating this HSC70 may be a heat-dependent HSC70 member. Finally, we constructed an expression vector to generate HSC70 in Escherichia coli BL21, which displayed immune cross-reactivity with mouse HSP70 antibody. In conclusion, the identification and expression of the white shrimp HSC70 gene present useful data for studying the molecular mechanism of heat shock response and the effect of heat shock proteins in shrimps’ cytoprotection. Published in Russian in Molekulyarnaya Biologiya, 2008, Vol. 42, No. 2, pp. 265–274. The text was submitted by the authors in English.  相似文献   

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