植物肌球蛋白的研究进展

肌球蛋白是依赖微丝的、把贮存在ATP中的化学能转化为机械能的分子马达。广泛存在于动、植物中,与信号传导、肌肉收缩、细胞器运动等有关。到现为止,肌球蛋白分类两类：传统肌球蛋白（肌球蛋白Ⅱ）与非传统肌球蛋白。除肌球蛋白Ⅱ外,其余的都是非传统肌球蛋白,植物肌球蛋白为其中的第Ⅷ、Ⅵ、Ⅷ类。然而,赵发清博干从丝瓜卷须中鉴定出一肌球蛋白（LFM174）,其分子量174KDa,可能属于传统肌球蛋白。LFM174具两个头、一个长约为100nm的尾,与肌球蛋白Ⅱ极为相似。不断出现的新技术将对肌球蛋白的研究产生影响。     

Dynamics and functions of the actin cytoskeleton during the plant cell cycle

In eukaryotic cells, the course of the cell cycle depends on correct cytoskeleton arrangement. The cell cycle consists of several phases, and in each of them the cytoskeleton has a unique structure and set of characteristics. The dynamics of the cytoskeleton together with its binding proteins greatly contribute to progression of the cell cycle. Here, we mainly review recent research on the dynamic distribution of the actin cytoskeleton and actin-binding proteins, and the mechanisms by which they affect the ...     

资汛

“粘着斑”的分子架构细胞外基质与一个细胞的肌动蛋白细胞骨架之间的物理联系由被称为“粘着斑”的细胞器组成,它们通过“整联蛋白”（或称整合素）发挥作用。它们在人体生理中具有根本性的重要性,因为它们调控细胞粘附、机械传感和控制细胞生长及分化的信号。现在,     

不同硒浓度对鸡胚软骨细胞的骨架与胞外基质中胶原微原纤维的影响

大骨节病是一种发生在我国低硒地带的地方病,病区的水、土、粮食以及病人的毛发、血液等的硒含量都处于低硒状态,补充Na_2SeO-3可明显预防此病的发生。大骨节病主要的病变是骨端软骨细胞坏死。微量元素Se对软骨细胞的生长、发育有无明显的作用?本文在离体条件下对这方面进行了初步探索。     

逆转录病毒复制早期阶段中有关的细胞因子

逆转录病毒复制的早期阶段包括：病毒一细胞膜融合、逆转录、病毒的双链DNA整合插入宿主细胞染色体。在这些过程中，逆转录病毒必须利用若干细胞因子，诸如特异的细胞表面受体、细胞骨架的某些组分和核质转运有关因子。本书是关于逆转录病毒复制早期作用机制的专著。     

Formins： Bringing new insights to the organization of actin cytoskeleton

The actin cytoskeleton is an important component of eukaryotic cell cytoskeleton and is temporally and spatially controlled by a series of actin binding proteins (ABPs). Among ABPs, formin family proteins have attracted much attention as they can nucleate unbranched actin filament from the profilin bound actin pool in vivo. In recent years, a number of formin family members from different organisms have been reported, and their characteristics are known more clearly, although some questions are still to be clarified. Here, we summarize the structures, func-tions and nucleation mechanisms of different formin family proteins, intending to compare them and give some new clues to the study of formins.     

Dynamic organization of actin cytoskeleton during the polarity formation and germination of pollen protoplasts

The formation of the polarity of pollen protoplast and the dynamics of actin cytoskeleton were observed by non-fixation, Alexa-Phalloidin probing and confocal laser scanning microscopy. Our results showed that the protoplast obtained from stored pollen contained numerous crystalline fusiform bodies to constitute a storage form of actin. When dormant pollen was hydrated, the actin cytoskeleton forms a fine network spreading uniformly in the protoplast. In the process of polarity formation and germination of pollen protoplast, actin filaments marshaled slowly to the brim, and then formed multilayer continuous actin filament bundles surrounding the cortical of the protoplast. When the protoplast was exposed to actin filament-disrupting drugs, such as Latrunculin A and Cytochalasin D, continuously arranged actin bundles were disturbed and in this condition, the protoplast could not germinate. But when exposed to actin filament stabiling drug-phalliodin, the dynamics of actin filaments in the protoplasts behaved normally and the protoplasts could germinate normally. These results were also confirmed by the pharmacology experiments on pollen grains. And when Latrunculin A or Cytochalasin D was washed off, the ratio of pollen germination was resumed partly. All the results above show that the dynamic organization of the actin cytoskeleton are critical in the cell polarity formation and germination of pollen protoplast, and that the reorganization of actin cytoskeleton is mainly due to the rearrangement of actin filament arrays.     

细胞骨架微管管壁中电子的隧道效应

该文基于细胞骨架微管结构的对称性,将其壁上的原丝纤维视为一维的动力学系统,采用“双势阱”模型和量子力学的基本方法,对发生在微管壁上的一根原丝纤维上电子的势垒穿透几率和由隧道效应引起的基态能级劈裂进行了理论计算,得到了一些有意义的物理结果.     

Cytoskeleton reorganization and FAK phosphorylation are involved in lanthanum （Ⅲ）-promoted proliferation and differentiation in rat osteoblasts

The effect of lanthanum ion (La³⁺) on osteoblast function and cytoskeleton is assessed in vitro. Osteoblasts were isolated from Sprague-Dawley fetal neonatal rats. Cell proliferation and gene expression levels of cbfa-1, alkaline phosphatase (ALP), osteocalcin (OC), bone sialoprotein (BSP) and osteopontin (OPN) were examined by cell counting and RT-PCR. Cytoskeleton F-actin was stained with rhodamine-conjugated phalloidin and was visualized by a confocal microscope. As the results, 10⁻⁸-10⁻⁴ M La³⁺-induced osteoblast proliferation on day 2. Data from the RT-PCR assay revealed that 10⁻⁶ M La³⁺ up-regulated the expression levels of ALP, BSP, and cbfa-1 on day 4, while it enhanced the expressions of OC and OPN on day 21. The F-actin cytoskeleton was strengthened and reorganized under the exposure of La³⁺. In addition, the phosphorylation of focal adhesion kinase (FAK) was significantly promoted in 24 h evaluated by Western blot analysis. These findings indicate that La³⁺ promotes osteoblast activity through the phosphorylation of FAK and reorganization of the cytoskeleton.     

人口腔上皮细胞骨架观察实验的建立

细胞骨架是真核生物细胞的重要结构,研究细胞骨架的形态对进一步研究其功能具有重要意义.以建立一种在光学显微镜下观察到清晰的人口腔上皮细胞的细胞骨架的实验方法为目的,从实验材料的预处理、 抽提时间、 固定时间三个方面对现有的实验方法进行了改进和优化.结果表明,以人口腔上皮细胞为实验材料,取材后置于1 mol/L的甘露糖中预...