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1.
A comparative study on the cytochemical localization of adenosine triphosphatase (ATPase) activity reaction in the cells of the apical meristem zone, elongation zone and root hair zone of tomato roots was carried out by electron microscopic observations of lead phosphate precipitation. The following experimental results have been obtained: In the meristematic cells of tomato roots, the heavy lead phosphate deposits indicating a very high activity of ATPase were localized at plasmalemma, plasmodesmata, endoplasmic reticulum, Golgi bodies, nucleoli and chromatin (Figs. 1—2). The reaction products of ATPase activity were also observed at some sites of ground cytoplasm and cell wall, but they were not found in little vacuoles and on tonoplast. In the cells of elongation zone, the ATPase activity at plasmalemma and plasmodesmata was as high as that in the meristematic cells of root tip, while the ATPase activity at nucleoli, chromatin, endoplasmic reticulum and Golgi bodies was markedly lowered. On the other hand, the high ATPase activity was produced on the tonoplast of the developing and enlarging vacuoles (Fig. 3). In the cells of root hair zone, the high ATPase activity was shown at plasmalemma, tonoplast and intercellular spaces, but the ATPase activity at nucleoli, chromatin and endoplasmic reticulum was wholly inactivated. (Figs. 4—7). The above results indicate that the ATPase activity with membranes and organelles is altered when the functions of cells and organelles change. Therefore, it is evident that the ATPase activity may be closely related to many physiological functions.  相似文献   

2.
The ultrastructural localization of adenosine tripkosphatase (ATPase) activity in cotyledon cells of tomato was carried out by use of the cytochemical method of lead phosphate precipitation, and the changes in ATPase activity during chilling stress of the tomato seedlings were studied. The following experimental results have been obtained: 1. The ATPase activity in the cotyledon cells of tomato seedlings germinated and grown at 28 ℃. was located at plasmolemma, plasmodesmata, nucleoli and nuclear chromatin chloroplast lamellae, many sites of cell wall, and the surface of cell wall bordering the intercellular spaces and their inclusions. 2. When the tomato seedlings were subjected to chilling treatment for 4 h. at 5 ℃., the ATPase activity in cotyledon cells was indifferent from that of non-chilling treated seedlings. After chilling treatment for 12 h. at 5 ℃., the reaction of ATPase activity at plasmolemma, and in cell wall and intercellular spaces was markedly reduced. though the high activity reaction of ATPase in nuclei and at chloroplast lamellae was still maintained. When the tomato seedlings were subjected to chilling stress for 24 h. at 5℃., the ATPase activity at plasmolemma and in cell wall was almost inactivated, while the ATPase activity in nuclei and at chloroplast lamellae was only slightly lowered. These results indicated that the chilling injury may influence firstly on the ATPase activity of cell surface (plasmolemma and cell wall). 3. The role of intercellular spaces used as the passage of materials and the process and mechanism of chilling injury are discussed.  相似文献   

3.
Using an affinity purified antibody raised against the RI-H fragment of rat intestinal lectin L-36, the latter protein has been identified within the esophageal epithelium by means of ultracryotomy followed by immunogold labeling. The epithelium consists of 4 morphologically distinct cell-types, namely, the basal, spiny, granular and squamous cells, and each of these exhibits a different immunolabeling pattern. The basal cells form a layer on the basal lamina, and in these a diffuse cytoplasmic staining is observed. This basal cell layer is overlaid by spiny cells that extend many cell processes into wide intercellular spaces. In these cells, immunogold particles are found only on small granular inclusions consisting of an electron-lucent homogeneous substance. The granular cells from a third layer over the spiny cells, and are characterized by a number of large granular inclusions with an electron-dense core rimmed by a less electron-dense substance. Immunogold labeling is found on these granules, both on the core and peripheral region. Squamous cell-types constitute the most superficial layer of the epithelium. They are without granular inclusions, and immunogold labeling is confined to the cytoplasmic surface of the thickened plasma membrane. These findings suggest that L-36 is produced in the basal cells as free cytosolic protein, then becomes progressively aggregated into the granular inclusions of the spiny and granular cells, and is eventually transferred onto the cytoplasmic surface of the squamous cell plasma membrane where it may interact with complementary glycoconjugate(s) located at this site. The membrane lining substance thus formed may play a role in stabilizing the squamous cell membranes, thereby maintaining the structural integrity of the epithelium against mechanical stress coming from the esophageal lumen.  相似文献   

4.
对生长分化期水稻胚乳细胞的质膜内陷进行了超微结构和磷酸酶的细胞化学研究。结果表明 ,胚乳细胞内的小泡、内质网常与胞间连丝相连 ;质膜形态多变 ,功能活跃 ,由局部起伏的波纹状发展成明显内陷 ,深浅不一 ,多呈袋状 ,袋中包含着大小不一的泡状物 ;有些内陷脱离质膜成为胞质中的囊泡 ,表现出活跃的内吞现象。除细胞间隙中含有圆球状的内含物外 ,在质膜内陷和囊泡中常含有大量的内含物。H ATP酶定位结果显示 ,质膜及其邻近的泡状物周围有酶的分布 ;而酸性磷酸酶定位在液泡、胞间隙和其中的泡状内含物周围 ;在质膜及其内陷形成的囊泡中有G6P酶的分布。这些结果表明胞间隙和质膜内陷在物质的运输中可能起着重要作用  相似文献   

5.
The ultracytochemical localization of ATPase in the secondary xylem cells during their differentiation and dedifferentiation in the girdled Eucommia ulmoides Oliv. was carried out using a lead phosphate precipitation technique. Throughout the differentiation, which is a typical programmed cell death (PCD) process, ATPase deposits increased in the nucleus but decreased and progressively disappeared in the cell organelles. At the same time, the distribution of ATPase increased in the inner face of the cell wall and pits with cytoplasmic degeneration. The results demonstrated that the PCD was an energy dependent active process and was controlled by nuclear genes. On the other hand, the distribution of ATPase in the intercellular spaces increased with the formation of the new cambium resulted from the dedifferentiation of the secondary xylem cells after girdling. However, ATPase was not found in the nucleus of the dividing cells, suggesting that nutrients were transported through protoplast during differentiation, and through both protoplast and apoplast during dedifferentiation. Thus, the energy required in cell division was provided mainly by intercellular spaces. These findings indicate that the dynamic distribution of ATPase reflected which cell component was actively taking part in the cell metabolism at various stages of the plant development, and its distribution was associated with the physiological state of the cell. Based on the characteristic distributions of ATPase, the critical stage of cell differentiation and the relationship between the critical stage and dedifferentiation were discussed.  相似文献   

6.
采用磷酸铅沉淀技术,对杜仲(Eucommia ulmoides Oliv.)次生木质部细胞分和脱化过程进行了ATPase的超微细胞化学定位。随着分化过程中细胞程序性死亡(programmed cell death,PCD)程度的加深,ATPase在细胞核上的分布由少变多,而在各种细胞器上的分布由有到无,并且随着细胞质的解体,ATPase在细胞壁内侧和纹孔处的分布也由少到多,说明它们的变化是由核基因  相似文献   

7.
在中国丰收11号大豆根瘤侵染细胞中,我们发现了一种电子密度很高,体积很大,形状为圆形或近似圆形,外面没有界膜,常位于胞间隙附近的特殊的细胞质内含物。高尔基体及其小泡,丰富的粗糙型内质网和核糖体常在它的附近,其中一些核糖体正沉积在它的表面。它主要是由核糖体凝聚而成,高尔基体和内质网在它的形成中也起了一定作用。它的内部含有颗粒状,纤维状,泡状和管状物质。它的出现似乎与侵染细胞固氮有关。  相似文献   

8.
Phase and electron microscopic studies have revealed that the supporting cells of the lateral-line canal-organ of Fundulus heteroclitus have a fine structure characterized by (1) mitochondria and vacuoles in the apical zone, (2) granular endoplasmic reticulum surrounding a core of Golgi complex in the middle zone, and (3) an indented nucleus in the basal zone. In the middle and basal zones, wide intercellular spaces separate the adjacent supporting cells, whose plasma membranes form long flap-like interdigitations across the intercellular spaces. Secretion of subcupular fluid and cupula, metabolic regulation through the intercellular spaces, and rigid support for the organ are discussed as possible metabolic and mechanical functions of the supporting cells essential for the lateral-line canal-organ.  相似文献   

9.
Summary The vagina of the rhesus monkey is lined by a stratified squamous epithelium. However, little is known regarding the cytochemical composition of its cell organelles and the substances found in the intercellular spaces. In this study we have examined the ultrastructural distribution of acid phosphatase in the vaginal epithelium. In basal and parabasal cells reaction product was found in some Golgi cisternae and vesicles and in a variety of cytoplasmic granules. Reaction product was also found in some, but not all, membrane-coating granules. In the upper layers of the epithelium, the membrane-coating granules extruded their contents and acid phosphatase was localized in the intercellular spaces. The possible roles of acid phosphatase in keratinization, desquamation, or modification of substances in the intercellular compartment are discussed.  相似文献   

10.
Bovine parotid glands exhibit outstanding structural differences when compared with those of non-ruminant mammals. The acini are tortuous, branched and lined with cells of different heights, imparting a scalloped appearance to acinar lumina. Numerous microvilli, ca. 1.5 μ in length, extend into the lumina and intercellular canaliculi. Intercellular canaliculi measure ca. 3 μ in diameter and interweave in close association with intercellular tissue spaces. Intercellular tissue spaces are separated from the extraacinar spaces across a basal lamina only, whereas junctional complexes guard canaliculi from direct continuity with tissue spaces and/or extraacinar spaces. Flattened cytoplasmic lamellae extend from adjacent acinar cells and loosely interdigitate with one another across the tissue spaces. Acinar cells contain more mitochondria and less granular endoplasmic reticulum than parotid glands of non-ruminant mammals. Two types of secretory material, in the form of inclusions which vary in size and electron density, are present in the acinar cells. Intercalated ducts connect acini with striated ducts which in turn, empty into collecting ducts located between gland lobules. In terms of frequency of “basal infoldings” and numbers of mitochondria, striated ducts of calf parotid glands are not as well developed as those of certain other salivary glands. Myoepithelial cells are most often present at junctions of acini and intercalated ducts where they may attach to both acinar and ductal epithelium. Nerve “terminals” were not observed on the epithelial side of basement membranes in relation to the secretory cells.  相似文献   

11.
Standard lead precipitation procedures have been used to examine the localization of ATPase activity during cytomixis in pollen mother cells of Lilium davidii var. willmottiae (Wilson) Roffill. Before cytomixis, cells at this stage of development show ATPase activity on plasma membrane, in the endoplasmic reticulum, dictyosomes, plastids, plasmodesmata, and in part of the groundplasm; however, there is no ATPase activity on the chromatin and nucleolus. During cytomixis, the chromatin substance begin to transfer from one cell to an adjacent cell, reaction product indicating ATPase activity is observed associated with the chromatin and nucleolus. ATPase activity is also found with the cistenae of both endoplasmic reticulum and dictyosomes, and some plastids. There is no deposition of ATPase reaction product associated with the plasm membrane and intercellular spaces. After cytomixis, the chromatin is little or no deposition of enzyme reaction product. ATPase activity, however, is consistenlly found within the intercellular space and on the plasm membrane, and also occur in the endoplasmic reticulum, dictyosome and plastid. The presence or absence of ATPase activity in the cell structure of pollen mother cells before, during or after eytomixis is discussed in relation to the active uptake or export of water for short-distance transport. It is also suggested that the intensive ATPase activity in the nucleus during cytomixis of pollen mother cells is evidence for a transport system involved in the active movement of the intercellular migrating ebromatin substance.  相似文献   

12.
The Leydig cells of viscacha (seasonal rodent) show cytoplasmic hypertrophy and regional distribution during the breeding period (summer-autumn). The dominant organelles are smooth endoplasmic reticulum (SER) and mitochondria. A moderately well-developed Golgi, abundant lipid inclusions, dense bodies like lysosomes in different stages, and centrioles are observed. Extensive or focal desmosome and gap-like junctions between neighbouring Leydig cells are present. These cells exhibit an evident hypotrophy and an increase in the number of dense bodies during the gonadal regression in winter (July and August). Cells in different stages of involution are observed in this period. Their nuclei are irregular and heterochromatic. The cytoplasm contains few mitochondria. The vesicular SER is scarse. Irregular and large intercellular spaces with microvilli and amorphous material are present. The junctional complexes are absent. The nuclear and cytoplasmic volume and development of SER and mitochondria increase during the recovery period (spring). The lipid inclusions decrease. Dilatations of the intercellular space with microvilli and limited by focal desmosome-like junctions are observed. In conclusion, the Leydig cells of Lagostomus maximus maximus show deep changes alongside the reproductive cycle. The photoperiod variations, through pineal hypothalamus pituitary axis and the hormone melatonin, are probably responsible for them. Moreover, the fall of serum and tubular testosterone would be one of the factors responsible for gonadal regression.  相似文献   

13.
Abstract. Acid phosphatase was found cytochemically in intercellular spaces in the root of Nymphoides peltata. Different methods, using lead salts and azo-dyes, gave similar results. Reaction product appeared on material, possibly cytoplasmic, within the intercellular spaces and also against the outer walls of cells which formed the intercellular spaces. Possible functions of acid phosphatase in intercellular spaces are discussed.  相似文献   

14.
Summary Ultrastructural studies on the Malpighian tubules of Glomeris marginata (Villers) reveal considerable morphological differences between the upper, fluid secreting, segment, and the lower segment which is at present of unknown function. Previous reports have shown that the upper tubule has a high permeability to compounds of high molecular weight. This may be accounted for by the fact that the epithelium shows very extensive intercellular spaces which are linked directly to junctions apparently specialised to provide a low resistance extracellular pathway between the haemocoel and the tubule lumen.Histochemical studies on the localisation of phosphatase enzymes reveal intracellular vesicles with acid phosphatase activity. The basal labyrinth of the lower tubule exhibits considerable alkaline phosphatase activity which is apparently identical in location to the enzyme revealed by two different ATPase localisation techniques.The authors are indebted to the Science Research Council for financial supportThe authors wish to thank Mrs. Margarita Petri for her technical assistance and advice  相似文献   

15.
NaCl胁迫初期 ,Na 主要在根和叶鞘中积累。相应地 ,根和叶鞘液泡膜ATP酶和焦磷酸酶水解活性、依赖ATP和PPi的质子泵活性及Na /H 逆向转运活性均明显增加 ,根和叶鞘的生长没有受到抑制。NaCl胁迫后期 ,Na 开始向地上部分运输并在叶片中积累。此时 ,叶片液泡膜质子泵和Na /H 逆向转运活性开始增加 ,根和叶鞘的Na/K比增加 ,其液泡膜ATP酶和焦磷酸酶水解活性、质子泵活性和Na /H 逆向转运活性下降。相应地 ,根和叶鞘的生长也下降。当保温介质中Na/K比超过 1时 ,液泡膜微囊ATP酶和焦磷酸酶活性均随Na/K比的增加而下降。表明非盐生植物液泡膜质子泵在盐胁迫的初期对Na 在液泡内的积累及其耐盐性起重要作用  相似文献   

16.
Acrosomal ATPase in starfish and bivalve mollusk spermatozoa   总被引:1,自引:0,他引:1  
ATPase activity was found in acrosomes of starfish and bivalve mollusk spermatozoa, using a cytochemical method with electron microscopy. The activity was located in central material of the starfish acrosome and in material lining the acrosomal membrane of the Mytilus acrosome, as well as in the basal part of the starfish acrosome. The ATPase activity in the former material was preferably activated by Ca2+, while that in the starfish basal material was preferably activated by Mg2+. Both types of activity persisted during and after the acrosome reaction. ATPase activity was also observed in the region of the axial filament complex of the flagella, in centrioles and in a basal matrix. ATPase in the acrosome also hydrolysed other nucleoside triphosphates. However, there was no detectable phosphatase activity, and little pyrophosphatase or 5′-nucleotidase activity. Evidence was obtained that adenylate kinase may be included in the acrosome. A possible role of the ATPase activity in the acrosome reaction is discussed.  相似文献   

17.
The fine structure of the epicyte of D. gigantea was investigated. The motility of the gregarine and the contractile elements are described. Four essential types of movements can be observed in this gregarine: (1) rolling up and pendular movements, (2) locomotion by gliding forward, (3) cytoplasmic streaming (Fig. 1), (4) peristaltic contractions (Fig. 2) which seem to be accompanied by the contraction of annular myonemes (Fig. 2). The epicyte is formed by the folding of the parasitic cell wall which is made from three membranes (Figs. 3 and 4). At the top of each fold one can see apical struts between the outer and middle membrane and apical filaments under the inner membrane (Fig. 3). In addition, the epicytic folds are covered by a cell coat which is made from tubular structures (Fig. 5). At the base of the epicytic folds can be observed the basal lamina (Fig. 3) composed of very fine fibrillar material with an average thickness of 2.5 nm (Fig. 6). These fibrils are oriented in the longitudinal axis of the gregarine. Beneath the epicytic fold in the ectoplasm are found the annular myonemes with a width of up to 0.5 micrometers (Fig. 7). They are composed of many fine fibrils with an average thickness of 5 nm. In young trophozoites, the myonemes also contain microtubuli (Fig. 8). Between the epicytic folds, the cell wall is interrupted by three different types of vesicles: the vesicles with an electrondense content (Fig. 9), the three-membranous vesicles (Fig. 10), and the hose-shaped vesicles (Fig. 11). Glycerol-extraction of the parasites was performed in order to define the contractile structures. After extraction the annular myonemes are difficult to recognize (Fig. 13). When ATP is added, the gregarine does not contract but the myonemes reappear after 3 to 4 min (Fig. 14). Differences can also be observed in the myoneme structure using electron microscopy: After extraction, the myonemes are composed of a very limp fibrillar network (Fig. 15) which becomes very dense after the action of ATP (Fig. 16). Glycerol extraction does not disturb either the apical struts and apical filaments or the fibrils of the basal lamina (Figs. 15--17). In addition, cytoplasmic fibrillar structures appear after glycerol extraction (Figs. 15 and 16). The experimental and electron microscope results indicate that the motility of the gregarine depends upon four different systems: (1) the ectoplasmic annular myonemes, (2) the apical structures in the undulating epicytic folds, (3) the cytoplasmic fibrils, and (4) the basal lamina.  相似文献   

18.
The outermost cell layer of the animal half of the newt blastula ( Triturus pyrrhogaster ) was examined to investigate intercellular junctions by transmission and scanning electron microscopy. A unique structure is observed at the terminal region of the intercellular junction. The structures are cytoplasmic ridges elevated from the cell surfaces, and their inner part is filled with spaces of various sizes. It is supposed that these ridges result from the encounter of cytoplasmic folds protruding from two neighboring cells.
Below the ridges, there is a short close junctional area which is followed by a long region of intercellular space intermittently bridged by cytoplasmic projections. Microvillus-like cytoplasmic processes on the apical cell surfaces, and microfilaments and microtubules in subsurface regions are observed in this material as in many other embryonic cells of amphibians.  相似文献   

19.
Leaf stomatal conductance measured and analysed in the canopies of two winter wheat varieties in the field revealed that the probability of adaxial to abaxial conductance ratio followed an approximately normal distribution with a peake value of about 1.5. The ratio changed with the developmental stages being maximium at the heading stage. Leaf stomata in wheat of the upper part of the canopy were more active and showed more pronounced diurnal change of conductance than those of the lower part. Stomatal conductance decreased from top to bottom in canopy as a negative exponential function. By comparing adaxial and abaxial conductances in the apical, middle and basal parts of a leaf, the distribution of the stomatal conductances of a wheat leaf was as follows: a steady decrease from the basal part of adaxial, through the middle and apical parts of the adaxial surface turning to the apical part of abaxial, and then the middle and lastly, the basal part of abaxial. Based on values of the correlation coefficients among the various stomatal conductance and average stomatal conductance, the authors suggested that optimal apical measurement of stomatal conductance would be at the middle and apical parts and that of abaxial would be at middle and basal parts.  相似文献   

20.
The sections from the upper part of the third internode, counted from the seed, in etiolated pea seedlings are studied for the distribution of two types of Intercellular spaces: the transparent and the dark. The transparent spaces represent the result of the water logging of passages originally water-lined, while the dark spaces are lined with a lipid-containing substance which may be impregnated with melted paraffin and which forms a ramifying network within the tissue. The intercellular material of the dark spaces has the appearance of a tube, since it concentrically lines the intercellular space, leaving a lumen for air or gas. It is a plastic, isotropic subslance which may be cut transversely and identified in successive sections of the inlernode as belonging to the same continuous material from the intercellular space. The dark and the transparent spaces have a distinct pattern of distribution in the growing internode, and the relative quantity of dark spaces present at different levels of the internode may be measured. The dark spaces predominate in those parts of the stem with a greater potential for growth, while the transparent spaces are located in the regions where growth has ceased or subsided. Since the paraffin is infiltrated instantaneously throughout the network of dark intercellular spaces, it is possible that these may represent a channel for the translocation of substances.  相似文献   

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