稻田蜘蛛混合种群空间分布模式动态分析(英文)

结果表明,在东方红农场稻田中总共有11科29属43种蜘蛛,其中早稻田中有8科19属43种,晚稻田中有10科27属36种。在水稻的不同发育阶段蜘蛛混合种群的空间分布模式存在差异。在早稻发育的前期、中期和后期,稻田蜘蛛混合种群的空间分布模式分别是聚集的、随机的和聚集的;在晚稻发育的前期、中期和后期,其空间分布模式依次是均匀的、聚集的和均匀的。同时,对其空间分布模式动态进行了初步分析。     

稻田害虫和捕食性节肢动物群落结构和动态

广西南宁市郊稻田害虫和捕食性节肢动物群落,由46科159种组成,其中害虫21科65种;捕食性昆虫12科39种;蜘蛛13科55种。早、晚稻构成群落的物种基本相似,但各物种的数量结构及优势种差异明显。文中分析了晚稻害虫、捕食性昆虫和蜘蛛亚群落的垂直分层、时空格局及其数量变动的原因。     

Visualization and Characterization of High-Order Chromatin Fibers under Light Microscope during Interphase and Mitotic Stages in Plants

Using genomic in situ hybridization with genomic DNA, high-order chromatin fibers were successfully exhibited under a light microscope through the cell cycle in barley, rice, maize and field bean. From the interphase to prophase and metaphase of mitosis, the fibers were basically similar. Each was estimated to be around 200 nm in diameter, but the strength of signals was not the same along the fiber length. Through the cell cycle a series of dynamic distribution changes occurred in the fibers. In the interphase, they were unraveled. At the early prophase they were arranged with parallel and mirror symmetry. During late-prophase and metaphase, the fibers were bundled and became different visible chromosomes. The parallel coiling and mirror symmetry structures were visible clearly until the metaphase. In anaphase they disappeared. During telophase, in peripheral regions of congregated chromosome group, borderlines of the chromosomes disappeared and the fibers were unraveled. This demonstrated that mitotic chromosomes are assembled and organized by parallel and adjacent coiling of the fibers and the fibers should be the highest order structure for DNA coiling.     

湖南稻田蜘蛛群落生态特点及控虫作用研究

总结近年来对湖南省境内不同地理、生态类型的稻田蜘蛛群落结构的研究结果;报道湖南稻田蜘蛛198种,隶属25科87属,及其常见类群和主要优势种:拟水狼蛛、食虫沟瘤蛛、八斑鞘腹蛛。并应用测定群落结构特征的多种指数公式比较分析不同地理、生态类型的稻田蜘蛛群落的时空格局特点、物种多样性差异、主要优势种差异以及农药对稻田蜘蛛群落结构的影响和蜘蛛群落对目标害虫的控制效应的定性定量分析结果。     

CELL DIVISION IN SPIROGYRA. I. MITOSIS

Dividing cells of Spirogyra sp. were examined with both the light and electron microscopes. By preprophase many of the typical transverse wall micro-tubules disappeared while others were seen in the thickened cytoplasmic strands. Microtubules appeared in the polar cytoplasm at prophase and by prometaphase they penetrated the nucleus. They were attached to chromosomes at metaphase and early anaphase, and formed a sheath surrounding the spindle during anaphase; they were seen in the interzonal strands and cytoplasmic strands at telophase. The interphase nucleolus, containing 2 distinct zones and chromatinlike material, fragmented at prophase; at metaphase and anaphase nucleolar material coated the chromosomes, obscuring them by late anaphase. The chromosomes condensed in the nucleoplasm at prophase, moving into the nucleolus at prometaphase. The nuclear envelope was finally disrupted at anaphase during spindle elongation; at telophase membrane profiles coated the reforming nuclei. During anaphase and early telophase the interzonal region contained vacuoles, a few micro-tubules, and sometimes eliminated n ucleolar material; most small organelles, including swollen endoplasmic reticulum and tubular membranes, were concentrated in the polar cytoplasm. Quantitative and qualitative cytological observations strongly suggest movement of intact wall rnicrotubules to the spindle at preprophase and then back again at telophase.     

The vesicular compartment of the mitotic apparatus in mammalian cells

Intracellular membranes might play an eminent role in regulating several events during mitosis: In this paper the appearance and changing configurations of the vesicular compartment of the mitotic apparatus of HeLa cells was studied from anaphase to telophase. In early prophase electron opaque and transparent membranous vesicles are found in the pericentriolar region outside the nucleus. During prometaphase when the nuclear envelope opens and starts to disappear, an increasing number of these vesicles appears in the mitotic apparatus near the chromosomes. During metaphase vesicles are spread all over the mitotic apparatus, the number of electron opaque vesicles decreases while the total amount of vesicles does not change significantly. Anaphase shows the same pattern of distribution in the half-spindle and in the midbody. In telophase the amount of electron opaque vesicles increases again. They are now found around vacuoles and near the newly appearing Golgi-cisternae. We assume that the electron opaque vesicles are derived from the Golgi- apparatus which disintegrates during prophase and reappears in late telophase. The change in the appearance of the different types of vesicles during metaphase coincides with drastic changes in the ionic milieu in the mitotic apparatus (Wolniak et al., 1983).     

农田蜘蛛群落结构及其多样性研究

本文对南宁地区农田自然蜘蛛群落和旱地狼蛛亚群落结构及其多样性进行了研究。 1.农田区蜘蛛群落有14科、41属、80种。主要成分是食虫瘤胸蛛、拟环纹狼蛛、拟水狼蛛、奇异獾蛛和豹蛛属种类,个体数以食虫瘤胸蛛最多。旱地狼蛛亚群落主要成分是奇异獾蛛和豹蛛属种类。 2.稻田区蜘蛛群落多样性指数以田埂杂草群落最高,早稻田群落最低。多样性、均匀度和种类丰富度时间格局是早、晚稻皆随时间序列增加。平均多样性、均匀度和个体数,晚稻均高于早稻。狼蛛更群落多样性和均匀度以草地最高。 3.应用群落比例相似性和聚类分析表明,拟环纹狼蛛与拟水狼蛛和奇异獾蛛与豹蛛属种类是组成当地农田区的水田和旱地生境具有代表性的两个狼蛛亚群落主要成分。 本文试图揭示农田生态系统中的稻田蜘蛛,在不受化学农药干扰下群落结构及其多样性变化,并以狼蛛亚群落为代表,比较农田区内不同生境的群落结构及多样性与生境生态特征的关系,为害虫防治和动物资源的利用提供参考。     

起源于籼稻体细胞培养的联会消失变异的细胞遗传学研究

对表现不育的体细胞培养再生植株作减数分裂细胞遗传学分析发现,一株由IR54幼穗外植体起源的不育株(二倍体)为部分联会消失变异。其减数分裂早前期染色体配对正常,在终变期及中期Ⅰ观察到了数目不等的单价染色体,后期Ⅰ出现各种数目的落后染色体。由于减数分裂时染色体不平衡而导致该再生植株不育。     

棉田蜘蛛混合种群空间格局分析及应用

1996年5月上旬至下旬,在山西运城地区临猗县,选择高水肥及中水肥棉田进行蜘蛛混合种群空间格局的调查分析。用经典频次法分析,大部分样本符合负二项分布,少数样本有多解和无解现象。9种聚集指标结果均符合聚集分布型,聚类分析结果表明,9种指标可按其性质分成3类。Iwao M~＃-m模型为M~＃=3.5151 1.4765 m,改进的M~＃-M模型为M~＃=2.6423 1.9587 m-0.0246 m~2,Taylor的幂法则式为S~2=22.089M~(2.6466),其结果均为聚集分布。应用以上分析结果,建立棉田蜘蛛混合种群调查的简化抽样方案。用零样出现的百分率来估计百株蜘蛛数量的指数回归式为:P_O=(0.6011/(0.6011 m)~(0.6011);用有蜘蛛的株率来估计百株蛛量,则用以下指数回归式:Y=256.52~(1.5345)。     

Early endosomes, late endosomes, and lysosomes display distinct partitioning strategies of inheritance with similarities to Golgi-derived membranes

The pattern of inheritance of compartments of the endocytic pathway has been rarely reported, and the precise mechanism(s) are yet to be elucidated. We used antibodies reactive to early endosomes (anti-EEA1), late endosomes (anti-LBPA and anti-LAMP-1), lysosomes (anti-LAMP-1) and trans-Golgi network (TGN) (anti-GOLGA4) to examine the inheritance of these compartments in fixed human HEp-2 cells. Prior to entering M phase, these compartments display a perinuclear bias in their cytoplasmic distribution with areas of local accumulation juxtaposed to the centrosome. The location of these compartments during mitosis was examined relative to each other, the chromosomes, centrosomes and the microtubule network. During M phase early endosomes and TGN-derived compartments share overlapping subcellular distributions. A portion of these compartments display discernible clustering around the separated and migrating centrosomes in prophase. At metaphase these compartments co-localise with the mitotic spindle, are absent at the metaphase plate and do not overlay the astral microtubules. At anaphase these compartments are concentrated between shortening kinetochore microtubules and centrosomes. In addition, they appear distributed over the elongating polar microtubules in the body of the cell. From telophase and into cytokinesis these compartments concentrate around the minus ends of the constricted remnants of polar spindle microtubules and re-establish a prominent presence juxtaposed to the centrosome. In contrast, there is little evidence of movement of late endosomes and lysosomes with migrating centrosomes in prophase, and these compartments are excluded from the mitotic spindle at metaphase. However, by the end of telophase, the subcellular distribution of a portion of late endosomes and lysosomes share overlapping distributions with that of early endosomes. We conclude a portion of endosomal compartments and Golgi-derived membranes undergo ordered partitioning based on the centrosome and mitotic spindle.     

Mitosis and microtubule organizational changes in rice root-tip cells

The pattern of change of the microtubule cytoskeleton of the root-tip cells of rice during mitosis was studied using immunofluorescence technic and confocal laser scanning microscopy. All the major stages of ceil division including preprophase, prophase, metaphase, anaphase and telophase were observed. The most significant finding was that in the preprophase cells microtubules radiating from the nuclear surface to the cortex were frequently seen. During development these microtubules became closely associated with the preprophase band and prophase spindie indicating that the microtubules radiating from the nuclear surface, the preprophase band and the prophazc spindle were structurally and functionally closely related to each other. Granule-like anchorage sites for the radiating microtubules at the muclear surface were often seen and the possibility that these gramle-like anchorage sites might represent the microtubule organizing centres was discussed.     

Individual nuclei in polykaryons can control cyclin distribution and DNA synthesis.

Nuclear patterns of cyclin (PCNA) distribution that subdivide S-phase (determined using PCNA autoantibodies specific for this protein) as well as [3H]thymidine incorporation followed by autoradiography have been used to determine the S-phase synchrony of homophasic polykaryons produced by polyethylene glycol (PEG)-induced fusion of populations of mitotic transformed human amnion cells (AMA) exhibiting the following average distribution of phases: prophase, 9%, metaphase, 60% (including early and late prometaphase), anaphase, 3.8%, telophase, 26.2% and interphase, 1%. Both synchronous and asynchronous polykaryons were generated from these fusions; the latter being frequently observed only amongst populations of multinucleated cells having three or more nuclei. These results are taken to imply that individual nuclei in these polykaryons can control cyclin distribution and DNA synthesis in spite of the fact that they share a common cytoplasm.     

The Nucleolus and Parachromatin of the Ascites Tumor Cell

1. A method is described for distinguishing the ribonucleoproteins of the nucleolus and parachromatin of ascitic tumor cells of the mouse. 2. In these cells the transfer of ribonucleoprotein from the nucleus to the cytoplasm can occur in two ways. (a) At the end of prophase the nucleolus separates from the chromosomes and nucleolar fragments are released into the cytoplasm. (b) During prophase the parachromatin is aggregated to form parachromatin bodies which are discharged into the cytoplasm, where they can be detected during metaphase, anaphase, and telophase. 3. A metachromatic form of RNA is demonstrable, and may be synthesized, in close relation to the chromosomes during prophase, metaphase, and anaphase. During telophase the distribution of metachromatic RNA changes, the chromatin loses its metachromasia, and intranuclear metachromatic parachromatin becomes evident.     

Effects of protein synthesis inhibition during plant mitosis

The role of protein synthesis in onion root tips during mitosis has been studied, by using synchronous cell populations. Incubation in cycloheximide (CHM) or anisomycin during early or middle prophase induces the return of these cells to interphase. Therefore, it is suggested that essential proteins are synthesized, which determine the continuation of the cells in mitosis. In late prophase these treatments caused a certain delay in the entry into further stages, suggesting that a protein synthesis probably occurs which determines the duration of the transition from metaphase to anaphase. Mitotic processes which develop after metaphase do not seem morphologically dependent on protein synthesis, in spite of the fact that one of them, the nucleolar reconstruction, is markedly dependent on RNA synthesis. Unexpectedly this reorganization increases its rate in the absence of protein synthesis.     

A comparison of the distribution of actin and tubulin in the mammalian mitotic spindle as seen by indirect immunofluorescence

Rabbit antibodies against actin and tubulin were used in an indirect immunofluorescence study of the structure of the mitotic spindle of PtK1 cells after lysis under conditions that preserve anaphase chromosome movement. During early prophase there is no antiactin staining associated with the mitotic centers, but by late prophase, as the spindle is beginning to form, a small ball of actin antigenicity is found beside the nucleus; After nuclear envelope breakdown, the actiactin stains the region around each mitotic center, and becomes organized into fibers that run between the chromosomes and the poles. Colchicine blocks this organization, but does not disrupt the staining at the poles. At metaphase the antiactin reveals a halo of ill-defined radius around each spindle pole and fibers that run from the poles to the metaphase plate. Antitubulin shows astral rays, fibers running from chromosomes to poles, and some fibers that run across the metaphase plate. At anaphase, there is a shortening of the antiactin-stained fibers, leaving a zone which is essentially free of actin-staining fluorescence between the separating chromosomes. Antitubulin stains the region between chromosomes and poles, but also reveals substantial fibers running through the zone between separating chromosomes. Cells fixed during cytokinesis show actin in the region of the cleavage furrow, while antitubulin reveals the fibrous spindle remnant that runs between daughter cells. These results suggest that actin is a component of the mammalian mitotic spindle, that the distribution of actin differs from that of tubulin and that the distributions of these two fibrous proteins change in different ways during anaphase.     

Localization and structure of snRNPs during mitosis. Immunofluorescent and biochemical studies

The distribution of U snRNAs during mitosis was studied by indirect immunofluorescence microscopy with snRNA cap-specific anti-m3G antibodies. Whereas the snRNAs are strictly nuclear at late prophase, they become distributed in the cell plasm at metaphase and anaphase. They re-enter the newly formed nuclei of the two daughter cells at early telophase, producing speckled nuclear fluorescent patterns typical of interphase cells. While the snRNAs become concentrated at the rim of the condensing chromosomes and at interchromosomal regions at late prophase, essentially no association of the snRNAs was observed with the condensed chromosomes during metaphase and anaphase. Independent immunofluorescent studies with anti-(U1)RNP autoantibodies, which react specifically with proteins unique to the U1 snRNP species, showed the same distribution of snRNP antigens during mitosis as was observed with the snRNA-specific anti-m3G antibody. Immunoprecipitation studies with anti-(U1)RNP and anti-Sm autoantibodies, as well as protein analysis of snRNPs isolated from extracts of mitotic cells, demonstrate that the snRNAs remain associated in a specific manner with the same set of proteins during interphase and mitosis. The concept that the overall structure of the snRNPs is maintained during mitosis also applies to the coexistence of the snRNAs U4 and U6 in a single ribonucleoprotein complex. Particle sedimentation studies in sucrose gradients reveal that most of the snRNPs present in sonicates of mitotic cells do not sediment as free RNP particles, but remain associated with high molecular weight (HMW) structures other than chromatin, most probably with hnRNA/RNP.     

黄蝉花生殖细胞有丝分裂期间微管的动态

用微管免疫荧光方法观察了黄蝉花生殖细胞在花粉管中进行有丝分裂时的微管动态。微管在不同分裂期的分布情形很不一样。当生殖细胞由花粉进入花粉管后,细胞便立刻开始分裂进入早前期,在这阶段微管以一个紧密微管网笼子形式存在生殖细胞内。之后,细胞进入中前期,在此阶段细胞核扩大,染色体变粗,而存在细胞内的微管网逐渐变为疏松散漫状,跟着细胞进入晚前期,而微管笼子则由网状变为纵向排列状。分裂进入早中期微管变细并呈波浪状,微管由笼子结构过渡到纺锤体结构。进入中期,纺锤体全部形成,在纺锤体内可以清楚地看到两种不同类型的微管束,一种附着在染色体上,而另一种则从一极延伸至另一极。跟着细胞进入早后期,在这一阶段姊妹染色体分开并分别移向两极,在赤道板位置微管明显减少。之后,细胞进入晚后期,姊妹染色体集中在两极,极端有新微管出现。在两个染色体团之间又汇集了许多类似成膜体微管的微管。细胞进入分裂末期,存在赤道板位置的微管又再次减少,而在中央部位则新形成一“成膜体联接区”,把两个新形成的精子连接着。     

大青沟森林植物群落主要木本植物种群分布格局及动态的研究

本文运用方差／均值比率法及聚集强度的某些指数研究了大青沟森林植物群落主要木本植物种群的分布格局及其动态。主要木本植物种群的分布格局大多为集群型,只有部分群落中大果榆、色木槭及家榆种群为随机分布。格局动态的分析表明,水曲柳、黄菠萝、春榆、大果榆种群幼苗—幼树—小树—中树—大树分布格局由集群分布逐渐变为随机分布,而蒙古栎由于较强的萌生性,大树阶段仍为集群分布。分析表明影响种群分布格局的因子大致可归纳为两类：一是物种本身的生物学特性,二是由环境条件引起的种内种间竞争;方差／均值比率法是一种较好的分析种群分布格局的方法。     

Dynamics of Spindle Formation and Its Inhibition by Chemicals

The formation of the mitotic spindle of the newt cell in tissue culture has been studied, using polarized light. The rate of formation was measured and it was shown that the spindle increased in length at a constant rate until the maximum was attained. During metaphase the spindle shortened to about 50 to 60 per cent of its original length, reaching a minimum just before anaphase. No birefringence was detected in late anaphase in the spindle region after the chromosome masses had separated. The effects of certain compounds which are believed to inhibit protein synthesis were investigated. Chloramphenicol added in early prophase prevented the formation of a spindle of normal length. The possible relation of chloramphenicol to the synthesis of spindle proteins is discussed.