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1.
1921年,Molish首先在光镜下发现植物叶片细胞核中有一种晶体状的内含物(见Weintraub等[1])。后来人们陆续在某些动、植物的细胞核中观察到了这种结构[2—4],并称之为核内含体(intranuclearinclusions)。Bigazzi[3]曾在45种桔梗科植物的细胞中看到了核内含体。但在离体培养的植物细胞中发现内含体的报道很少,至今仅在榛子组织培养分生细胞中看到了类似的结构[5]。我们在对西洋参体细胞胚胎发生进行超微结构研究的过程中发现,在胚性愈伤组织和胚状体细胞的核和细胞质…  相似文献   

2.
斜带髭鲷外周血嗜中性粒细胞核内包涵体的超微结构   总被引:1,自引:0,他引:1  
目的在对斜带髭鲷(Hapalogenys nitens)外周血细胞结构进行透射电镜观察时发现嗜中性粒细胞存在大量的核内包涵体,系统研究了这些核内包涵体的超微结构,以探讨其来源和形成过程。方法应用电镜技术对这些核内包涵体的超微结构进行研究。结果斜带髭鲷外周血嗜中性粒细胞的核内包涵体可分为假包涵体和真包涵体两种类型,包涵体中的内含物来自胞质。胞核首先是以核膜内陷的方式将胞质及其各种有形成分包绕进核内而在核质外层形成具有双层膜包裹的典型假包涵体,随后假包涵体双层膜降解消失而转化成无被膜包裹的真包涵体,即核内糖原包涵体。结论假包涵体是形成真包涵体的开始阶段。随着假包涵体向真包涵体的转变,包涵体内含物的组成及其超微结构也出现了显著变化。  相似文献   

3.
利用初级三体定位水稻光敏核不育基因   总被引:7,自引:0,他引:7  
自 1 973年 Ramanunjam首次获得三体 ( 2 n=2 x 1 =2 5)植株以来 ,已报道的粳型初级三体有日本晴 NT和籼型初级三体 IR36、Sona、广陆矮 4号 [1 ]及籼型初级三体 30 37[2 ]等。获得细胞学证据并用于定位研究的仅有日本晴三体和 IR36三体 [3,4]。目前 ,利用形态标记和分子标记定位水稻光敏核不育基因的报道较多 ,且涉及到第 5、7和第 1 2三条染色体 [5,6] 。我们拟以粳型光敏核不育系为父本 ,台中 65初级三体为母本配组 ,定位光敏核不育基因 ,对粳型光敏核不育基因定位结果进行验证 ,以期为光敏核不育的利用与研究提供理论依据。1  材料…  相似文献   

4.
在发育的新生组织中 ,来自种子胚乳储存蛋白的降解和氨基酸分解代谢产生的氨由谷氨酰胺合成酶 ( Glutamine synthetase,GS)重新同化 ,生成的谷氨酰胺 ( Gln)被转运到正在生长着的部分。GS是高等植物氮素代谢的关键酶 [1] ,这个酶能同化不同来源的氨。 GS有多种同工酶 ,存在于植物的各种组织和器官中。它们是由一小的同源但分离的核基因家族编码的 [2 3 ] ,这些不同的 GS在植物氮素同化中起着非重叠的作用 [4] ,它们的表达受到环境、发育进程以及组织或细胞类型等许多因素的影响。在大多数已研究过的植物叶片中存在两种 GS,即胞液型GS(…  相似文献   

5.
通过扫描电镜对凤仙花属(Impatiens)14种植物的种子表皮微形态特征进行了观察。根据种皮表面纹饰及衍生物的特点,将该属植物的种皮微形态特征划分为4种类型,即光滑型、颗粒型、网状型和隆起型,后两者又可细分为若干亚型,其中负网状亚型和网状-丘状隆起亚型为首次报导。研究表明,14种凤仙花属植物种子表皮微形态特征差异显著,它们作为属内种的分类鉴别特征具有重要价值;种子表皮的微形态学特征与其植物体的部分表型特征具有相关性,在一定程度上反映了属内类群的分化。  相似文献   

6.
中国飘拂草属植物果皮微形态   总被引:1,自引:0,他引:1  
利用扫描电子显微镜对国产莎草科飘拂草属4组18系42种1变种植物果皮微形态特征进行观察,并作了系统描述。研究表明,飘拂草属植物在纹饰类型,超微结构等方面存在着明显的种间差异,具有分类学意义。根据纹饰及微形态特征的不同,支持将褐鳞飘拂草和知风飘拂草各自作为独立的种。依照果皮纹饰的差异,飘拂草属可分为4种类型(1)瘤(疣)-网状复合纹饰;(2)瘤(疣)状纹饰;(3)网状纹饰;(4)脊-疣状复合纹饰。其中(1)和(3)类型的纹饰根据网脊曲直不同各自又可分为2个亚型。  相似文献   

7.
初级三体是非整倍休的变异类型之一,它是指植物细胞核内多了1条额外的同源染色体,即2n+1。对大麦来说,2n+1=15,意味着某一个同源组的染色体有3条。自1915年 Blakeslee3)第一次在曼陀罗(Datura stramonium) 发现三体以来,在自然界陆续发现了约10种植物的三体。同时通过射线或快速中子处理,或从人工三倍体中分离得到三体。在大麦方面, Smith"和Kattermann[5]最初报道了自然发生的三体,Kerberidl和Tsuchiya[10]报道了人工获得的初级三体。  相似文献   

8.
P[8]b基因亚型是国内外新近发现的A组人轮状病毒(HRV)VP4基因的一种新亚型,本研究旨在建立有效鉴别HRV P[8]a和P[8]b基因亚型及P[4]和P[6]基因型的VP4基因打点杂交分型方法,并运用此方法对2009~2010年首都儿科研究所附属儿童医院门诊及住院腹泻患儿中P[8]b基因亚型HRV的流行情况及其G/P基因组合情况进行研究。通过对GenBank序列数据库可检索到的国内外HRV各种P基因型及亚型的VP4基因序列应用相关软件进行基因分析,在不同基因型别间核苷酸变异密集而相同P基因型内核苷酸高度保守的的位置设计各型别探针,并分别以本实验室上传GenBank的北京HRV地方株P[4]和P[6]基因型及P[8]a和P[8]b亚型的VP4基因作为相应型别探针的合成引物的设计模板及探针经PCR合成的合成模板,合成地高辛素标记的DNA探针。经测序验证所建立的VP4基因杂交分型方法结果可靠。对门诊88例(55%,88/160)及住院79例(70.5%,79/112)HRV腹泻患儿的P分型结果显示P[8]a亚型仍为主要型别,前者为96.6%(85/88),而后者为62.0%(49/79);P[8]b亚型在住院HRV感染腹泻患儿中占较高比例(27.9%,22/79),虽然其在门诊HRV感染患儿中也存在,但仅占2.3%(2/88);另外单纯P[4]基因型HRV感染仅在住院腹泻患儿中检测到1例(1.3%,1/79),而P[6]基因型在门诊及住院HRV感染腹泻患儿中均未检测到;本组标本中HRV P[8]b亚型主要与G9基因型组合。本研究表明G9P[8]b型HRV在北京腹泻儿童中有流行。  相似文献   

9.
植物病毒病的风轮状内含体   总被引:2,自引:0,他引:2  
在目前公认的34个植物病毒组中,有25个病毒组的病毒能在寄主植物中产生内含体。能否产生内含体及内含体的形态结构是病毒组的主要特征之一。植物病毒内含体最早由steere williams于1953年在感染烟草花叶病毒(TMV)的烟草叶片中观察到,呈晶板状(Crystalline plates)。以后人们渐渐认识到内含体与病毒病害密切相关,但从发现至今近40年内,对内含体的产生及其功能仍不很清楚。  相似文献   

10.
初级三体是非整倍休的变异类型之一,它 是指植物细胞核内多了1条额外的同源染色 体,即2n+1。对大麦来说,2n+1=15,意 味着某一个同源组的染色体有3条。自1915年 Blakeslee[3]第一次在曼陀罗(Datura stramonium) 发现三体以来,在自然界陆续发现了约10种植 物的三体。同时通过射线或快速中子处理,或 从人工三倍体中分离得到三体。在大麦方面, Smith"和Kattermann[5]最初报道了自然发生 的三体,Kerber[6]和Tsuchiya[10]报道了人工获 得的初级三体。  相似文献   

11.
The ultrastructure of intranuclear inclusions in leaf mesophyll cells of Davidia involucrata was investigated with electron microscopy. Intranuclear inclusions occur generally in the cells of young and mature leaves. They consist of numerous bundles aggregated by several fibres (diameter about 10 nm), sometimes a few of bundles turn to tubules enveloped by fibres. Authors suggested that it is a new subtype (F2) of intranuclear fibrillar inclusion.  相似文献   

12.
13.
Collapsin response mediator protein-2 (CRMP-2) is a member of the CRMP/TOAD/Ulip/DRP family of cytosolic phosphoproteins involved in neuronal differentiation and axonal guidance. CRMP-2 mediates the intracellular response to collapsin 1/semaphorin 3A, a repulsive extracellular guidance cue for axonal outgrowth. The mutation of UNC-33, a Caenorhabditis elegans homolog of CRMP-2, results in abnormality of microtubules in neurites, but the mechanism of CRMP-2 action remains to be clarified. Here, we report that overexpression of human CRMP-2 in Neuro2a cells, a mouse neuroblastoma cell line, results in blebbing of the cytoplasm. Furthermore, some cells exhibited intranuclear inclusions, which were labeled with antibodies to CRMP-2 and tubulin. CRMP-2 was found to be associated with microtubule bundles in the spindles at the metaphase and in the midbodies at the late telophase in mitotic cells. Thus, it is most likely that failure of complete disassembly of the spindle microtubules during mitosis is responsible for the formation of these intranuclear inclusions. We suggest that CRMP-2 functions by regulating the dynamics of microtubules.  相似文献   

14.
Electron microscopic evidence demonstrated that dimethyl sulfoxide (DMSO) induces formation of giant intranuclear microfilament bundles in the interphase nucleus of a cellular slime mold, Dictyostelium. These giant bundles are approximately giant bundles are approximately 3 micrometer long, 0.85 micrometer wide, and composed of microfilaments 6 nm in diameter. Studies in which glycerinated cells were used showed that these microfilaments bind rabbit skeletal muscle heavy meromyosin, forming typical decorated "arrowhead" structures, and that this binding can be reverted by Mg-adenosine triphosphate. These data verify that the intranuclear microfilaments are the contractile protein actin, and that DMSO affects intranuclear actin, inducing the formation of such giant bundles. The intranuclear actin bundles appear at any developmental stage in two different species of cellular slime molds after treatment with DMSO. The native form of the intranuclear actin molecules and their possible functions are discussed, and it is proposed that the contractile protein has essential functions in the cell nucleus.  相似文献   

15.
Spinal and bulbar muscular atrophy (SBMA, Kennedy's disease) is one of a group of progressive neurodegenerative diseases resulting from a polyglutamine repeat expansion. In SBMA the polymorphic trinucleotide CAG repeat in exon 1 of the androgen receptor (AR) gene is increased, resulting in expansion of a polyglutamine tract. Patient autopsy material reveals neuronal intranuclear inclusions (NII) in affected regions that contain only amino-terminal epitopes of the AR. Cell models have previously been unable to produce intranuclear inclusions containing only a portion of the AR. We report here the creation of an inducible cell model of SBMA that reproduces this important characteristic of disease pathology. PC12 cells expressing highly expanded AR form ubiquitinated intranuclear inclusions containing amino-terminal epitopes of the AR as well as heat shock proteins. Inclusions appear as distinct granular electron-dense structures in the nucleus by immunoelectron microscopy. Dihydrotestosterone treatment of mutant AR-expressing cells results in increased inclusion load. This model mimics the formation of ubiquitinated intranuclear inclusions containing the amino-terminal portion of AR observed in patient tissue and reveals a role for ligand in the pathogenesis of SBMA.  相似文献   

16.
The presence of intranuclear and cytoplasmic inclusions in cells of embryogenic callus and developing embryoids from tissue cultures of Panax quinquefolius L. was described. These cellular structures were not found in non-embryogenic cells. The size of intranuclear and cytoplasmic inclusions seemed to be related to the developmental status of the cell.  相似文献   

17.
Confocal microscopy allowed us to localize viral nonstructural (NS) and capsid (VP) proteins and DNA simultaneously in cells permissively infected with Aleutian mink disease parvovirus (ADV). Early after infection, NS proteins colocalized with viral DNA to form intranuclear inclusions, whereas VP proteins formed hollow intranuclear shells around the inclusions. Later, nuclei had irregular outlines and were virtually free of ADV products. In these cells, inclusions of viral DNA with or without associated NS protein were embedded in cytoplasmic VP protein. These findings implied that ADV replication within an infected cell is regulated spatially as well as temporally.  相似文献   

18.
Summary Intranuclear filamentous inclusions were found in the normal endocrine cells of the avian stomach and pancreas. These inclusions were composed of a bundle of closely packed filaments (6–8 nm in diameter), being ultrastructurally similar to those found in the nucleus of various neurons. Most of them appeared as single rod- or spindle-shaped bodies; aggregations of two or more inclusions were rarely seen within a single nucleus. Cells with an intranuclear inclusion often contained a cytoplasmic fibrillar bundle similar to the intranuclear inclusion.  相似文献   

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