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*

定性和定量分析了在大鼠2/3肝切除前8h热休克(46℃,30min)处理(HS-PH)的肝再生期间(0-144h)保持性热休克蛋白70/诱导性热休克蛋白68(HSC70/HSP68)分布和含量变化、酸性磷酸酶(ACP)和碱性磷酸酶(AKP)分布、种类和活性变化.并把上述结果同只进行热休克(46℃,30min)(HS)和只进行2/3肝切除(PH)时这些分子的变化进行了比较.发现三种处理均可提高ACP、AKP活性和HSC70/HSP68表达量,但它们的变化规律不同.进一步分析发现,HS-PH后ACP活性增强是与140kD酶活性增加有关,而AKP活性增强则与140和160-180kD的酶活性增加有关.根据实验结果推测,ACP、AKP和HSC70/HSP68均在肝细胞的热休克反应和肝再生中起作用;它们可能均参与这些过程中的信号传导,但ACP可能在启动肝细胞增殖中起主导作用,AKP和HSC70/HSP68可能在胞质分裂中起主导作用.     

热休克蛋白、蛋白水解酶和磷酸酶在大鼠肝再生中的含量和活性变化

本文以２／３肝切除（ｐａｒｔｉａｌ ｈｅｐａｔｅｃｔｏｍｙ,ＰＨ）大鼠为模型,探讨了ＰＨ后酸性和碱性磷酸酶（ａｃｉｄ ａｎｄ ａｌｋａｌｉｎｅ ｐｈｏｓｐｈａｔａｓｅｓ,ＡＣＰ和ＡＫＰ）,构成性热休克蛋白７０／诱导性热休克蛋白６８（ＨＳＣ７／ＨＳＰ６８）,酸性和中性蛋白水解酶在肝再生期间（０－１４４ｈ）的动态变化。结果显示,在肝切除后的肝再生期间;（１）ＡＣＰ和ＡＫＰ均出现两个活性高峰（４和４８ｈ     

果蝇的热休克反应

热休克反应最早在果蝇中发现,其过程伴随着一系列特殊蛋白--热休克蛋白（HSPs）的增量表达.热休克蛋白包括多个家族,它们在热休克反应中表现出复杂的表达调控机制,并具有组织和发育阶段特异性.研究热休克反应具有重要的生物学意义,在医学、工业等的应用前景十分广阔.     

人热休克蛋白70和热休克固有蛋白70的基因克隆和表达

目的:克隆人热休克蛋白70(HSP70)和热休克固有蛋白70(HSC70)基因,并在大肠杆茵中表达,获得重组蛋白.方法:用RT-PCR法从HepG2细胞中扩增HSP70及HSC70cDNA序列.测序后,将相应的cDNA插入pRSET-A表达载体,在大肠杆菌中表达,重组蛋白纯化后用SDS-PAGE及Western Blotting分析.结果:DNA序列结果显示.本研究所获得的HSP70及HSC70 cDNA序列与参考序列一致.将全长cDNA分别插入表达质粒后,转化BL21(DE3)细菌,在IPTG的诱导下,表达产物SDS-PAGE显示相应的分子量(70kDa)位置有明显的蛋白条带.Western Blotting结果证实了其为目的蛋白,经镍树脂柱纯化,获得了相应的重组多肽.结论:成功构建了原核表达重组质粒HSP70-pRSET-A和HSC70-pRSET-A,并获得了纯化的重组人HSP70和HSC70蛋白,为进一步研究这两种蛋白的结构、功能及临床应用奠定了基础.     

短隔连续部分肝切除（SISPH）对大鼠肝ACP、AKP、HSC70／HSP68和PCNA的影响

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.     

热休克蛋白和蛋白水解酶与生物的应激反应

1962年,法国学者Ritossa在研究果蝇多线染色体时发现,果蝇一旦经热或化学处理,就会诱导其多线染色体产生一些特异的染色体膨大,即激活一些基因的表达。这些基因的表达产物热休克蛋白(HSP)已被纯化,基因也逐渐被分离。以后进一步研究发现,几乎所有生物,当受到各种应激因子(生物、生理、物理、化学等)刺激时,其细胞和生物体会合成一套保守的多肽即热休克蛋白,从而保护生物免受应激     

香烟烟雾和脂多糖对大鼠肺组织热休克蛋白70表达的影响

目的观察香烟烟雾和脂多糖对大鼠肺组织Hsp70表达的影响。方法48只成年雄性Wistar大鼠随机分为6组:健康对照30d组、健康对照3个月组、单纯薰香烟30d组、单纯薰香烟3个月组、单纯气管注入脂多糖组、薰香烟30d加气管注入脂多糖组,每组8只。采用SABC免疫组化法观察Hsp70在各组大鼠肺组织中的表达。结果(1)健康对照30d组、健康对照3个月组、单纯薰香烟30d组、单纯薰香烟3个月组Hsp70阳性产物的平均吸光度值分别为0·194±0·027,0·189±0·025,0·339±0·049,0·147±0·033。单纯薰香烟30d组与健康对照组30d相比大鼠肺组织Hsp70水平显著升高(P<0·05);单纯薰香烟3个月组与健康对照3个月组相比大鼠肺组织Hsp70水平显著降低(P<0·05);单纯薰香烟3个月组与单纯薰香烟30d组相比大鼠肺组织Hsp70水平显著降低(P<0·05)。(2)健康对照30d组、单纯气管注入脂多糖组、薰香烟30d加气管注入脂多糖组Hsp70阳性产物的平均吸光度值分别为0·194±0·027,0·285±0·059,0·143±0·024。单纯气管注入脂多糖组与健康对照30d组相比大鼠肺组织Hsp70水平显著升高(P<0·05);薰香烟30d加气管注入脂多糖组与健康对照30d组相比大鼠肺组织Hsp70水平显著降低,差异具有显著性(P<0·05);薰香烟30d加气管注入脂多糖组与单纯气管注入脂多糖组相比大鼠肺组织Hsp70水平显著降低(P<0·05)。结论香烟烟雾或脂多糖短期暴露使大鼠肺组织Hsp70表达升高;香烟烟雾长期暴露或香烟烟雾与脂多糖短期联合暴露使大鼠肺组织Hsp70表达降低。提示Hsp70可能与慢性阻塞性肺疾病的发病有一定关系。     

The heat shock protein HSP70 and heat shock cognate protein HSC70 contribute to antimony tolerance in the protozoan parasite leishmania

Antimony-containing drugs are still the drugs of choice in the treatment of infections caused by the parasite Leishmania. Resistance to antimony is now common in some parts of the world, and several mechanisms of resistance have been described. By transfecting cosmid banks and selecting with potassium antimonyl tartrate (SbIII), we have isolated a cosmid associated with resistance. This cosmid contains 2 copies of the heat shock protein 70 (HSP70) and 1 copy of the heat shock cognate protein 70 (HSC70). Several data linked HSP70 to antimony response and resistance. First, several Leishmania species, both as promastigotes and amastigotes, increased the expression of their HSP70 proteins when grown in the presence of 1 or 2 times the Effect Concentration 50% of SbIII. In several mutants selected for resistance to either SbIII or to the related metal arsenite, the HSP70 proteins were found to be overexpressed. This increase was also observed in revertant cells grown for several passages in the absence of SbIII, suggesting that this increased production of HSP70 is stable. Transfection of HSP70 or HSC70 in Leishmania cells does not confer resistance directly, though these transfectants were better able to tolerate a shock with SbIII. Our results are consistent with HSP70 and HSC70 being a first line of defense against SbIII until more specific and efficient resistance mechanisms take over.     

Constitutive heat shock protein 70 (HSC70) expression in rainbow trout hepatocytes: effect of heat shock and heavy metal exposure

The 70-kDa family of heat shock proteins plays an important role as molecular chaperones in unstressed and stressed cells. The constitutive member of the 70 family (hsc70) is crucial for the chaperoning function of unstressed cells, whereas the inducible form (hsp70) is important for allowing cells to cope with acute stressor insult, especially those affecting the protein machinery. In fish, the role of hsc70 in the cellular stress response process is less clear primarily because of the lack of a fish-specific antibody for hsc70 detection. In this study, we purified hsc70 to homogeneity from trout liver using a three-step purification protocol with differential centrifugation, ATP-agarose affinity chromatography and electroelution. Polyclonal antibodies to trout hsc70 generated in rabbits cross-reacted strongly with both purified trout hsc70 protein and also purified recombinant bovine hsc70. Two-dimensional electrophoresis followed by Western blotting confirmed that the isoelectric point of rainbow trout hsc70 was more acidic than hsp70. Using this antibody, we detected hsc70 content in the liver, heart, gill and skeletal muscle of unstressed rainbow trout. Primary cultures of trout hepatocytes subjected to a heat shock (+15 degrees C for 1 h) or exposed to either CuSO(4) (200 microM for 24 h), CdCl(2) (10 microM for 24 h) or NaAsO(2) (50 microM for 1 h) resulted in higher hsp70 accumulation over a 24-h period. However, hsc70 content showed no change with either heat shock or heavy metal exposure suggesting that hsc70 is not modulated by sublethal acute stressors in trout hepatocytes. Taken together, we have for the first time generated polyclonal antibodies specific to rainbow trout hsc70 and this antibody will allow for the characterization of the role of hsc70 in the cellular stress response process in fish.     

Isoform pattern of inducible HSP 70 in the rat myocardium after heat shock]

The hsp 70 content was measured in the myocardium of a control rat group, in the group of rats 24 hours following a heat shock and in the group of rats 48 hours after a heat shock. In 24 hours after the heat shock, a major inducible hsp 70 with molecular weight of 71 kDa and pI about 5.8 occurred which was utterly absent in myocardial cytosol from control animals. In addition, there was an increase in polypeptide fraction with molecular weight of 73 kDa and pI about 5.6 (HSX73). In 48 hours after the heat shock, first the inducible hsp 70 with molecular weight of 71 kDa and pI about 5.8 disappeared which was found in 24 hours; secondly, HSX73 decreased to the control level and, thirdly, several isoforms pronouncedly accumulated with molecular weight of about 71 kDa and pI ranging from 5.9 to 6.3. Thus, the isoform composition of stress proteins induced by heat shock strongly depends on the time after the stress exposure. Furthermore, the accumulation of more acidic isoforms precedes the accumulation of alkaline ones.     

The neuroprotective potential of heat shock protein 70 (HSP70)

In response to many metabolic disturbances and injuries, including stroke, neurodegenerative disease, epilepsy and trauma, the cell mounts a stress response with induction of a variety of proteins, most notably the 70-kDa heat shock protein (HSP70). Whether stress proteins are neuroprotective has been hotly debated, as these proteins might be merely an epiphenomenon unrelated to cell survival. Only recently, with the availability of transgenic animals and gene transfer, has it become possible to overexpress the gene encoding HSP70 to test directly the hypothesis that stress proteins protect cells from injury. A few groups have now shown that overproduction of HSP70 leads to protection in several different models of nervous system injury. This review will cover these studies, along with the potential mechanisms by which HSP70 might mediate cellular protection.     

Differential gene expression of HSC70/HSP70 in yellowtail cells in response to chaperone-mediated autophagy

A cell line derived from the tailfin of the marine teleost yellowtail fish Seriola quinqueradiata was established to examine cellular temperature regulation in an ectothermic animal. Three cytosolic members of the HSP70 family, heat-shock cognate proteins HSC70-1, HSC70-2 and heat-shock protein HSP70, were isolated from cultured yellowtail cells as stress-responsive biomarkers. Expression of hsp70 was heat-inducible, in contrast to the hsc70-1 gene product, which was expressed constitutively. In addition, expression of hsc70-2 was only induced under severe heat-shock conditions. Subcellular fractionation and immunocytochemistry showed localization of HSC70/HSP70 in the lysosomes, indicating that chaperone-mediated autophagy is induced by heat shock. Thus, chaperone-mediated autophagy is assisted by HSC70/HSP70, and heat-inducible expression of the genes encoding these proteins may be responsible for survival and adaptation under heat-shock conditions in fish cells.     

大鼠肝生长发育过程中ACP、AKP、HSC70/HSP68和PCNA的变化(英文)

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