辛德毕斯病毒在BHK—21细胞中繁殖过程的研究

辛德毕斯病毒(Sindbis virus)在BHK—21细胞中繁殖的一步生长曲线表明,病毒感染后2小时便可产生大量的子代病毒;感染后6小时,病毒滴度达到最高峰,为109TCID50/ml电镜技术显示了病毒粒子的形态结构与形态发生过程。本文还对SbV的代谢合成动态及对宿主细胞的影响进行了研究和讨论。     

衣藻淀粉核中存在类角蛋白中间纤维网架

采用选择性抽提结合 ＤＧＤ（ｄｉｅｔｈｙｌｅｎｅ ｇｌｙｃｏｌ ｄｉｓｔｅａｒａｔｅ） 包埋电镜技术在衣藻（Ｃｈｌａｍｙｄｏｍ ｏｎｓａ ｓｐ．）淀粉核中观察到直径１０ ｎｍ 的纤维网架,以哺乳动物角蛋白抗体进行免疫胶体金标记,在淀粉核区域有很强的特异性结合,间接免疫荧光染色得到相似结果,表明在衣藻淀粉核中存在类角蛋白中间纤维网络骨架     

镉诱导蚯蚓金属硫蛋白的分离纯化及其溶液构象的研究

镉诱导蚯蚓匀浆液经热沉淀,乙醇沉淀后,经凝胶过滤ＳｅｐｈａｃｒｙＳ－２００柱层析,得三个镉结合蛋白峰,分子量依次为４０,１７及９ｋＤ。这三个组份再分别经ＤＥＡＥＳｅｐｈａｒｏｓｅ Ｆａｓｔ Ｆｌｏｗ柱层析,分别得三、三、二个镉结合蛋白峰。根据光谱学特征、巯基含量及氨基酸组成等分析,认为凝胶过滤第二峰为金属硫蛋白（ＭＴ）,其经ＤＥＡＥ柱层析所得三个峰为ＭＴ三个亚型。对蚯蚓ＭＴ三个亚型在不同ＰＨ条件下     

低分子量神经丝蛋白(NF-L)的体外组装

利用超速离心和离子交换层析技术,从牛脊髓中分离纯化了神经丝蛋白三组分:NF-L,NF-M和NF-H。应用电镜负染色和金属投影方法研究神经丝的形态结构与NF-L的体外组装,结果表明:神经丝由10nm的核心纤维与外周的丝状突起组成;在近似生理条件下,NF-L可在60min内组装成10nm纤维,纤维由4根亚丝缠绕而成;在碱性缓冲液中,NaCl能促进NF-L装配成短纤维,这种10nm的短纤维无法连接成长纤维。     

Nuclear reassembly in vitro is independent of nucleosome/chromatin assembly

Ｃｈｒｏｍａｔｉｎｉｓｍａｄｅｕｐｏｆｒｅｇｕｌａｒｌｙｓｐａｃｅｄｓｕｂｕｎｉｔｓ,ｎｕｃｌｅｏｓｏｍｅｓ.Ｉｎｅｕｋａｒｙｏｔｉｃｃｅｌｌｓ,ｃｈｒｏｍａｔｉｎｉｓａｓｓｅｍｂｌｅｄｉｍｍｅｄｉａｔｅｄｌｙａｆｔｅｒＤＮＡｒｅｐｌｉｃａｔｉｏｎ,ｂｕｔｉｎｃｅｌｌｆｒｅｅｓｙｓｔｅｍｓ,ｉｔｃａｎｂｅａｓｓｅｍｂｌｅｄｉｎｄｅｐｅｎｄｅｎｔｏｆＤＮＡｒｅｐｌｉｃａｔｉｏｎｗｈｅｎｅｘｏｇｅｎｏｕｓＤＮＡｗａｓａｄｄｅｄｔｏｅｇｇｏｒｏｏｃｙｔｅｅｘｔｒａｃｔｓｏｆＸｅｎｏｐｕｓｌａｅｖｉｓ.Ｔｈｅ…     

Nuclear lamina in plant cells

By using selective extraction and diethylene glycol distearate (DGD) embedment and embedment-free electron microscopy, the nuclear lamina was demonstrated in carrot and Ginkgo male generative cells. Western blotting revealed that the nuclear lamina was composed of A-type and B-type lamins which contained at least 66-ku and 84-ku or 66-ku and 86-ku polypeptides, respectively. These lamin proteins were localized at the nudear periphery as shown by immunogold-labelling. In situ hybridization for light microscope and electron microscope showed that plant cells have the homologous sequences of animal lamin cDNA. The sorting site of lamin mRNA is mainly distributed in the cytoplasm near the nudear envelope. The data have verified that there indeed exists nudear lamina in plant cells.     

哺乳动物细胞去核产物(胞质体及核体)的结构与功能研究

1967年Carter发现细胞松弛素可以诱发组织培养细胞的自发排核之后,Prescott(1972)借助细胞松弛素存在下的离心处理,使这一排核现象普遍化,从而确立了体外细胞去核的标准方法。经过不断改进(croce et al., 1974;Veomett et al., 1976;Lucas etal., 1976;Wigler et al., 1975),现在,这一技术已广泛应用于细胞学研究的各个重要领域(Mc Burney et al., 1979;Goldman et al., 1974;du Bols et al., 1980)。细胞去核技术及其应用的研究在我国已有初步开展(陈瑞铭等,1979;沈鼎武等,1980)。本实验对二种上皮型传代细胞系进行了去核手术,用扫描电镜和透射电镜对所获得的胞质体     

Relation between nuclear envelope and nuclear lamina in nuclear assembly in vitro

Xenopus laevis egg extracts cell-free nuclear assembly system was used as an experimental model to study the process of nuclear lamina assembly in nuclear reconstitution in vitro. The experimental results showed that lamin was involved in the nuclear assembly in vitro. The assembly of nuclear lamina was preceded by the assembly of nuclear matrix, and probably, inner nuclear matrix assembly provided the basis for nuclear lamina assembly. Inhibition of normal assembly of nuclear lamina, by preincubating egg extracts cell-free system with anti-lamin antibodies, resulted in abnormal assembly of nuclear envelope, suggesting that nuclear envelope assembly is closely associated with nuclear lamina assembly.     

非细胞体系核重建过程中两类膜泡在环形片层及核被膜形成中的作用

非洲爪蟾卵经钙离子载体A 23187激活后,在10,000g下离心得到爪蟾卵提取物。Lambda DNA加入上述提取物可构建出染色质结构,并在染色质表面重建核被膜,同时在染色质外的区域形成环形片层。核被膜与环形片层有相似的发生途径,它们都是由两类在形态、大小、膜结构上有明显差别的膜泡融合而来。首先是直径200nm的圆形小膜泡相互融合成双层膜片层,同时核孔复合体在双层膜上大量装配,以这些双层膜片层为基础,光滑的大膜泡与之融合导致环形片层的扩张与核被膜的成熟。