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1.
高粱细胞质雄性不育系3197A(3A)在常温条件下是不育的(Figs.11&2),经热激(45℃)诱导不同程度地恢复了育性(Figs.13&4),为研究其不育机理提供了线索。热激2h后,3A中即可产生一类线粒体热激蛋白(HSPs)。其中,分子量为70kD的HSP70含量最高,也最为稳定。不过,3A中HSPs的稳定性弱于保持系3197B(3B)(Fig.2,Panels1~4)。放线菌素D抑制HSPs的合成,而氯霉素无此作用(Fig.2,Panels5&6),表明:HSPs是由核基因编码、在细胞质中合成、再跨膜转运到线粒体中的。3A幼穗经热激后,线粒体的总蛋白量猛增了2.7倍(Fig.3),达到3B的水平,育性亦变为可育的。Fig.4表明:HSP70反义链cDNA(R1)能进入到3B花药细胞中,并与靶RNA(HSC70mRNA)结合,而对照、正义链cDNA(D)链无此反应。由此、再增加一个通用保守序列的反义链cDNA(R2)、共两个探针(R1、R2),可以检测到:3A在常温下没有能力合成HSC70mRNA(Fig.5),而在热激条件下,转变为有能力(Fig.6)。启示:3A在热激条件下由不育转变为可育  相似文献   

2.
活性氧参与生物体内复杂的代谢过程。本文对它在家蚕个体发育过程中的生物学功能进行了初步探讨。 取1岁龄家蚕蛹分别注射H2O2、脱皮激素(Ecdn)、保幼激素(JH)和还原型谷胱苷肽(GSH),培养;定期取样测定家蚕体内H2O2含量。 对家蚕整个幼虫期(Fig.1),尤其是大眠期(Fig.2)、化蛹期(Table1)、蛹期(Fig.3-a,b,c)以及成虫期(Fig.4, Table 2)的研究结果表明,家蚕体内H2O2代谢具有如下特点:(1)入眠、化蛹、化蛾和死亡前H2O2含量都显著下降;(2)幼虫期1-3龄H2O2含量逐步下降,4~5龄H2O2含量回升,蛹期和成虫期H2O2含量与4~5龄接近;(3)每个龄期的中期H2O2含量最高;(4)CAT活性与H2O2含量呈负相关变化,前者迟于后者;另外,CAT活性远远大于SOD活性;(5)Ecdn、GSH处理可以降低家蚕蛹期H2O2含量,并使其提前下降,JH、H2O2处理含量下降,并相应地提早推迟化蛾;(6)成虫期雄蛾H2O2含量、SOD和CAT活性都显著高于同时期雌蛾。家蚕体内H2O2含量的变化与其发育密切相关。H2O2含量下降是变态的信号;家蚕成虫期H2O2 在性别上的  相似文献   

3.
近年发展起来的昆虫细胞-杆状病毒基因工程系统具有良好的优越性:(1)表达产量高,(2)产物的免疫原性、功能性类似于天然产物,(3)适用于悬浮及无血清培养。本实验中,将外源基因hGH克隆至质粒pVL1393,形成转移载体pVL1393/hGH(Fig.1&2)。与昆虫核多角体病毒AcNPV基因组DNA共转染秋粘虫细胞Sf9(Fig.3),pVL1393/hGH与AcNPV基因组DNA发生同源重组,取代多角体蛋白基因。经空斑分析纯化得到不含多角体,单一表达的重组病毒rAcVhGH(Fig.4),感染滴度达到2.03x108PUF/mL。经反复实验,105细胞/mL感染6~7天后收获培养上清液,可得到表达量为40μg/mL的hGH蛋白(Fig.5,6&7)。  相似文献   

4.
将抗癌胚抗原(CEA)单链抗体基因插入家蚕杆状病毒转移载体pBacPAKHis, 与修饰的家蚕核型多角体病毒BmBacPAKDNA共转染家蚕细胞, 经同源重组得到含有在多角体蛋白基因启动子控制下的抗CEAScFv 基因的重组病毒BmBacScFv。用重组病毒分别感染家蚕细胞和幼虫, 在两者中均得到了高效表达, 产物分子量为28kD, 前者占细胞总蛋白的6 % , 后者为0 .3 mg/ 蚕。目的基因在家蚕细胞和幼虫中表达产物经Ni2+IDASepharose6B亲和柱纯化, 前者纯度可达90% 以上, 后者纯度较低; 纯化后的融合蛋白具有CEA 结合活力, 其亲和常数分别为5 .4×108/mol·L- 1 和2.3 ×108/mol·L-1 , 略低于其亲本单抗E7B10 2.7 ×109/mol·L- 1 。  相似文献   

5.
研究了氮离子注入对耐辐射异常球菌(Deinococcusradiodurans)细胞内超氧化物歧化酶(SOD)活性的影响及其对MnSOD的诱导。结果表明,当20keV氮离子的注入剂量低于8×1014ions/cm2时,D.radiodurans中SOD活性变化不大,当剂量在8×1014~60×1014ions/cm2范围内时,SOD的活性随着注入剂量的增大逐渐提高,但大于60×1014ions/cm2时,则逐渐下降;加入对不同金属辅基的SOD同工酶活性抑制剂H2O2和氯仿乙醇的研究表明,中高剂量下氮离子注入诱导的是D.radiodurans中MnSOD活性的提高,在正常生理条件及小于8×1014ions/cm2的剂量下,D.radiodurans中SOD总活性主要由FeSOD构成  相似文献   

6.
研究了氮离子注入对耐辐射异常球菌(Deinococcusradiodurans)细胞内超氧化物歧化酶(SOD)活性的影响及其对MnSOD的诱导。结果表明,当20keV氮离子的注入剂量低于8×1014ions/cm2时,D.Radiodurans中SOD活性变化不大,当剂量在8×1014~60×1014ions/cm2范围内时,SOD的活性随着注入剂量的增大逐渐提高,但大于60×1014ions/cm2时,则逐渐下降;加入对不同金属辅基的SOD同工酶活性抑制剂H2O2和氯仿乙醇的研究表明,中高剂量下氮离子注入诱导的是D.Radiodurans中MnSOD活性的提高,在正常生理条件及小于8×1014ions/cm2的剂量下,D.Radiodurans中SOD总活性主要由FeSOD构成  相似文献   

7.
三种毛茛的核型研究   总被引:5,自引:0,他引:5  
对3种(含1变种)毛莨属植物进行了核型研究,其染色体数目及核型资料为首次报道。三叶毛莨(RanunculusjaponicusThunb.var.ternatifoliusL.Liao.)有两种核型。即基本型2n=2x=14=6m+4sm+4st(2SAT)和杂合型2n=2x=14=6m+4sm+4st(1SAT),前者核型的特征是其随体较大,而后者核型变异发生在第2对和第3对同源染色体异形上,并  相似文献   

8.
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   

9.
本研究以兔为实验材料,对细胞核移植过程中显微操作、电融合、电活化以及移核胚的培养等基本问题进行了研究。对兔进行PMSGhCG超数排卵,收集成熟卵母细胞和16细胞胚;后者经胰蛋白酶消化,去除胶膜和透明带,在不含Ca2+、Mg2+的分离液中分成单个卵裂球;然后,分别对两者做CB预处理;首次尝试采用Wiladsen法,去除卵母细胞核、并将单个卵裂球注入透明带,同时、与McGrathSolter法进行比较;通过电融合使供体核进入去核的卵母细胞内;将所得移核胚在体外或在中间受体内培养并观察。结果表明:一、Wiladsen法与McGrathSolter法比较,核移植操作的成功率及以后的电融合率均无明显差异(Tab.1)。相对于后者,Wiladsen法更简便、易于掌握并提高去核率。二、hCG超排注射后13~15h,观察卵母细胞发现:其中,678%保留有第一极体。此时的卵子若去除1/3胞质量,去核率可以达到583%。若推迟去核时间,笫一极体退化,失去去核标志。三、比较不同电脉冲条件,发现强度为063kv/cm,持续160μs的一次电脉冲可获较高移核胚的融合率(70.8%)(Tab.2);并可使611%的成熟  相似文献   

10.
家蚕胚胎发育中过氧化氢的代谢(英文)   总被引:2,自引:0,他引:2  
过氧化氢(H_2O_2)是生物体内主要的活性氧来源之一。在超氧化物歧化酶(SOD)、过氧化氢酶(CAT)等的催化作用下,H_2O_2。被降解,释放出活性氧。所以,生物个体发育过程中体内H_2O_2、SOD和CAT含量的变化反映着H_2O_2的代谢水平。另外,家蚕是蚕卵滞育昆虫,实验设计考虑到了滞育前后可能会有的差别。取产后10分钟内的卵为供试材料。采用即时浸酸法解除卵滞育。采用比色法和氧电极法测定并比较家蚕胚胎滞育形成与解除过程中过氧化氢的代谢。结果表明:(1)受精初期(0~4h),H_2O_2含量在2.5h时达到峰值(Fig.1),相应地SOD活性处于较高水平,而CAT活性处于最低水平(Fig.2);(2)胚胎发育过程中(即时浸酸解除滞育),H_2O_2含量除168~216h处于低水平外均显著高于滞育卵(Fig.3),SOD活性分别在72h、168h,形成小大两峰,后期显著高于滞育卵(Fig.4),而CAT活性72-192h保持平稳,随后急剧上升,前期显著低于滞育卵,后期相反(Fig.5);(3)滞育形成过程中H_2O_2水平变化平缓(Fig.6),SOD活性前期剧烈变动,但后期保持平稳(Fig.7),CAT活性逐步升  相似文献   

11.
正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

12.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

13.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

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15.
Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.  相似文献   

16.
Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE.  相似文献   

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18.
Shen  Jia-Yuan  Li  Man  Xie  Lyu  Mao  Jia-Rong  Zhou  Hong-Ning  Wang  Pei-Gang  Jiang  Jin-Yong  An  Jing 《中国病毒学》2021,36(1):145-148
正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).  相似文献   

19.
In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.  相似文献   

20.
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