热激蛋白与园艺植物的耐冷性

园艺植物受到一定时间的高温胁迫处理后其耐冷性提高 ,这与热激条件下诱导产生的新蛋白(即热激蛋白 )有关。综述了热激蛋白及其与园艺植物抗冷性关系的研究进展     

热激蛋白与植物的抗逆性

热激蛋白Heat-Shock Protein(HSP)又称热休克蛋白或应激蛋白(Heat-Stress Protein),是细胞在应激原(如高温)刺激下所生成的一组蛋白质.     

热激因子结合蛋白(HSBP)研究进展

综述了HSF-结合蛋白(HSBP)的结构特点,在热激反应中的作用,以及HSBP对热激转录反应的负调控.     

热激锻炼诱导猕猴桃耐热性研究

以美味猕猴桃(Actinidia deliciosa)品种秦美组培苗为试材,研究了热激锻炼对猕猴桃耐热性的诱导。试验结果表明,热激锻炼抑制了高温胁迫下猕猴桃叶片叶绿素的分解、细胞膜透性的增大和MDA含量的增加,使H2O2含量维持在较低的水平,增强了高温胁迫下抗氧化酶(SOD、CAY、POD、APX)活性和抗氧化剂(ASA、Pro)含量。说明热激锻炼诱导猕猴桃获得了耐热性。     

高温胁迫下糙皮侧耳胞内钙离子对热激蛋白基因表达的调控

以糙皮侧耳(Pleurotus ostreatus)菌株CCMSSC00389为材料,研究高温胁迫(40℃、120min)下钙离子的响应及其对热激蛋白的调控。在高温胁迫条件下,在培养基中添加胞内钙离子螯合剂、胞外钙离子螯合剂、钙调蛋白抑制剂、质膜钙通道抑制剂、三磷酸肌醇受体拮抗剂,利用钙离子特异性荧光探针检测菌丝体胞内钙离子含量,采用荧光定量PCR检测热激蛋白的基因表达量。结果表明,高温胁迫促进胞内钙离子浓度升高,增加Hsp60、Grp78、Hsp90、Hsp104等4种热激蛋白的基因表达量;培养基中添加钙离子螯合剂或抑制剂会降低胞内钙离子浓度,抑制这些热激蛋白的基因表达。研究结果表明高温胁迫会诱导糙皮侧耳胞内钙离子浓度升高,参与信号转导,从而调控热激蛋白的表达来缓解高温胁迫引起的伤害。     

植物小G蛋白ROPs生物学功能研究进展

ROP(Rho-related GTPases from plants)是一类信号小G蛋白,为高等植物所特有,且分布广泛。近年来已引起社会的广泛关注,从各种植物中分离出的Rop数量也在逐渐增加。本研究分析了多年以来拟南芥、水稻、大麦、番茄、烟草、辣椒、马铃薯等植物中小G蛋白ROPs生物学功能研究进展,并对小G蛋白ROPs在生物学功能上的最新研究进行综述,为研究其他植物小G蛋白ROPs奠定基础,进而为其他植物ROP蛋白功能研究提供借鉴。     

Effect of protein kinase C on the expression of myocardial HSP70 mRNA during myocardic ischemic preconditioning in rabbits

AIM:To study the relationship between myocardial HSP70 and PKC during myocardial ischemic preconditioning(IPC). METHODS: PKC inhibitor, polymyxin B(PMB) and PKC activator, phorbol 12-myristate 13-acetate(PMA) were applied to the models of myocardial ischemia/reperfusion in vivo and in vitro in rabbits, respectively, and the ventricular functions, PLA₂ in the serum, and the expression of mycardial HSP70 mRNA were examined. RESULTS:IPC decreased PLA₂ activity, improved the left ventricular function and increased the expression of myocardial HSP70 mRNA. Howerer, all these effects of IPC could be blocked by PMB. Interestingly, PMA mimicked IPC with attenuating the injuries of cardial myocytes and increasing myocardial HSP70 mRNA expression. CONCLUSION:PKC is involved in the myocardial HSP70 expression in case of ischemic preconditioning.     

Effect of HSP70 on HBV replication

AIM: To investigate the role of heat shock protein 70(HSP70)in hepatitis B virus (HBV) replication. METHODS: The effect of HBV replication on the expression of HSP70 was analyzed by RT-qPCR. The overexpression efficiency of HSP70 was confirmed by Western blot. The effect of HSP70 overexpression on HBV DNA replicative intermediates was analyzed by RT-qPCR and Southern blot. The effects of HSP70 overexpression on the expression level of HBV 3.5 kb mRNA and HBV core protein were measured by RT-qPCR and Western blot, respectively. The Effect of HSP70 overexpression on HBV promoter activity was detected by dual luciferase reporter system. RESULTS: The mRNA levels of HSP70 were inhibited by HBV replication. Overexpression of HSP70 repressed the expression of HBV DNA replicative intermediates, 3.5 kb mRNA and core protein, as well as HBV core promoter activity. CONCLUSION: HBV replication inhibits the expression of HSP70. Overexpression of HSP70 represses HBV replication. These data suggest that HSP70 repressed HBV replication by inhibiting HBV core promoter activity.     

热处理提高采后杜果抗冷性与蛋白质含量变化的关系

 以‘紫花’卡亡果为试材，探讨了采后热处理提高抗冷性的效果及其与蛋白质含量变化的关系。结果表明：38^oC 热空气处理0.5 ~3 d极显著地提高了紫花卡亡果抗冷性；热处理提高了卡亡果的蛋白质含量，并且热处理的卡亡果在2^oC低温贮藏及室温后熟期间蛋白质含量也保持较高水平；热处理提高了热稳定蛋白在可溶性蛋白中所占的比例。这些结果表明，热处理导致的卡亡果蛋白质含量增加与抗冷性的提高有关，热处理诱导产生的热稳定蛋白是使卡亡果具有抗冷性的重要原因。     

Progress in stress-induced heat shock signaling pathways

A lot of diseases (e.g., acute infarction and infections) and the diversity of harmful environmental changes, including elevating temperature, heavy metals and oxidants damage many kinds of proteins in organism. The denatured proteins usually evoke endogenous adaptive cellular mechanisms called heat shock response. After the activation, heat shock factors (HSFs) bind with heat shock element (HSE). This progress induces heat shock protein (HSP) expression, then facilitates repair of misfolded proteins, and finally inhibits the cell death (both necrosis and apoptosis) pathways. This review will introduce the structures and functions of HSF, HSP and HSE and details on the signaling process of HSP regulation by HSF.     

热激减轻柿果冷害及其与脂氧合酶的关系

为研究采后柿果实冷害发生机理,探讨热激延缓采后柿果冷害的技术措施,以扁花柿果为试材,研究了经48℃热空气处理3h后,在1℃下冷藏时,热激对柿果冷害、脂氧合酶活性和膜脂脂肪酸含量的影响。结果表明,热激延缓了脂氧合酶活性的上升,其棕榈酸和硬脂酸的相对含量低于对照,而亚油酸和亚麻酸相对含量反而高于对照,并降低柿果冷害指数,但对油酸相对含量则无明显影响。这表明,热激减轻柿果冷害可能与抑制脂氧合酶活性和提高果实亚油酸和亚麻酸相对含量有关。     

茄子花药低温胁迫培养及耐冷性诱导

以 6个茄子品种为试材 ,在低温胁迫条件下进行花药培养。结果表明 5～ 6℃低温胁迫处理可诱导花药形成耐冷性愈伤组织 ,在MS +NAA(0 .0 2mg·L-1) +ZT(1.0mg·L-1)培养基上耐冷性愈伤组织的分化率达到31.6 % ,由耐冷性愈伤组织再生植株的低温伤害率明显低于原品种     

茄子耐冷性生理生化指标的研究

 研究了8 个耐冷性不同的茄子材料对低温的反应。结果表明, 茄子的耐冷性与电导率在5 ℃下呈显著负相关, 与可溶性糖含量及脯氨酸含量均呈显著正相关, 且材料间差异较明显; 18 ℃下种子活力指数与茄子的耐冷性呈极显著正相关。以上测定项目均可作为茄子耐冷性生理生化指标。     

西瓜野生种质耐冷性基因连锁的RAPD标记

运用ＲＡＰＤ技术进行了西瓜野生材料ＰＩ４８２３２２耐冷性基因连锁的分子标记的研究,找到了一个分子连锁标记ＯＰＧ１２／１９５０与耐冷基因连锁,其遗传距离为６．９８ｃＭ。     

Taurine reduced oxygen free radical production induced by homocysteine in electron transport chain and homocysteine inhibites taurine transporter in mitochondria membrane

AIM: To observe effects of homocysteine and antagonized effects of taurine on electronic leakage and free radical production in myocardial mitochondria. METHODS: Myocardial mitochondria of rat heart was isolated, and was broken by supersonic wave to prepare submitochondria. Recombinant of succinic acid cytochrome c reductase was prepared with mitochondria of porcine heart. They were co-incubated with homocysteine and/or taurine with various concentration. The H₂O₂ and O₂^- were determined by chemiluminescence methods. The taurine transporter of heart mitochondria and its propert, and effects of homocysteine on its function were studied with glass filter. RESULTS: Homocysteine stimulated oxygen free radical production in heart mitochondria, submitochondria, and succinic acid cytochrome c in a concentration-dependent manner. Although taurine itself did not affect oxygen free radical production, taurine did inhibit oxygen free radical production in mitochondria, submitochondria and succinic acid cytochrome c in a concentration-dependent manner. Taurine transporters of Na⁺-dependent were existed in mitochondria membrane. Homocysteine inhibited taurine transtport in mitochondria in a concentration-dependent manner. CONCLUSIONS: Taurine inhibited electronic leakage and oxygen free radical production induced by homocysteine in electron transport chain. There were taurine transporters in mitochondria membrane, and transport functions of taurine transporter were inhibited by homocysteine.