共查询到20条相似文献,搜索用时 31 毫秒
1.
Hong Wang George P. Slater Larry C. Fowke Mohammed Saleem Adrian J. Cutler 《In vitro cellular & developmental biology. Plant》1991,27(2):70-76
Summary The cell wall regeneration on protoplasts derived from maize mesophyll cells was compared with wall regeneration on protoplasts
derived from suspension cultured cells using light microscopy, transmission electron microscopy, and mass spectrometry. The
time course of cell wall regeneration has shown that the mesophyll protoplasts regenerated walls much slower than the protoplasts
derived from cultured cells. Moreover, cell wall materials on the mesophyll protoplasts were often unevenly distributed. Electron
microscopy has further demonstrated that the mesophyll protoplasts have less organized and compact walls than the protoplasts
from cultured cells. Chemical analysis revealed that the mesophyll protoplasts had a lower ratio ofβ-(1–3)-glucan toβ-(1–4)-glucan than protoplasts from cultured cells. The significance of these results for the viability and development of
protoplasts in culture is discussed.
National Research Council of Canada paper no. 32458. 相似文献
2.
Division of nuclei without cytokinesis proceeds in growing protoplasts ofSchizosaccharomyces pombe. Prior to regeneration of the complete cell wall and reversion the protoplasts contain 1–7 nuclei, protoplasts with 1–2 nuclei
are most frequent. When regeneration of the wall is postponed by adding snail enzymes to the growth medium, protoplasts with
a higher number of nuclei (2–4) occur. Multinuclear protoplasts can revert to cells. During the first cytokinesis the protoplast
with the regenerated cell wall is divided into two cells by a septum, distribution of nuclei between the two cells being probably
incidental. More than only a single nucleus can pass to the revertants even during the second cytokinesis. Septation of protoplasts
occurs also during a partial blockage of the wall formation by the snail enzyme preparation, however, reversion to cells can
never be observed here (it occurs only after transfer of protoplasts to the medium without the enzyme preparation). The growing
and reverting protoplasts represent a very good model system for studying relations among individual processes of the cell
cycle, primarily growth of the cell, nuclear cycle and cytokinesis. Yeast protoplasts are often utilized as models for studying
morphogenic processes, relations among regeneration of the cell wall, including division of the nucleus (karyokinesis) and
cytokinesis. 相似文献
3.
Dr. Marie Havelková 《Protoplasma》1972,75(4):405-419
Summary The growth, cell wall regeneration, and the reversion of the protoplasts ofNadsonia elongata andSchizosaccbaromyces pombe cultivated in nutrient media containing snail enzyme was studied by light and electron microscopy. The protoplasts grew in the presence of snail enzyme and an incomplete cell wall composed of fibrils was formed on their surface. Thus, the presence of snail enzyme inhibited the completion of cell wall structure and, consequently, the reversion of the protoplasts to normal cells. The transfer of these protoplasts to medium free from snail enzyme led first to the completion of the cell wall and then to the reversion of the protoplasts to normal cells. The reported experiments confirmed that the regeneration of the complete cell wall preceded the protoplast reversion. 相似文献
4.
L. C. Fowke C. W. Bech-Hansen O. L. Gamborg J. P. Shyluk 《American journal of botany》1973,60(4):304-312
Protoplasts were prepared from cultured cells of Ammi visnaga (Umbelliferae) by enzymatic digestion of the cell walls and examined microscopically. Staining of fresh protoplasts with Calcofluor and silver hexamine demonstrated the apparent absence of wall material. Protoplasts contained more cell organelles than the whole cells, particularly endoplasmic reticulum and associated polysomes. The plasmalemma of most protoplasts appeared smooth; some protoplasts were connected by structures resembling plasmodesmata. Multinucleates resulting from fusion were frequently observed. 相似文献
5.
Angelika Neuhäuser Walter Klingmüller und Fritz 《Molecular & general genetics : MGG》1970,106(2):180-194
Summary Conidia of an actidione-sensitive wildtype strain of Neurospora crassa were irradiated with UV-light. They were then plated into nutrient-agar, either with or without actidione. The latter plates were incubated for several hours, before nutrient agar containing actidone was layered onto the plates. Colonies formed in both sets of plates were isolated as actidione-resistent. They were studied further by genetic and biochemical means.Pre-incubation of the irradiated conidia before subjecting them to the action of actidione increased the mutant yield considerably, as compared to immediate plating with the drug. E.g. a 13 hours pre-incubation gave ca. 100 times more resistent colonies than were obtained without pre-incubation (Fig. 2). Their resistent phenotype was stable on vegetative propagation.17 mutants were mapped by crossing them with suitable tester-strains. Of them, 14 were found to belong to linkage group I, the remaining to linkage group V. The mutants are, therefore, considered as characterizing resp. genes act-1 and -2 of Hsu (1963).
Act-1 and -2 mutants were crossed with suitable auxotrophic strains to obtain auxotrophic, actidione-resistent isolates. These were combined on minimal medium with auxotrophic, actodione-sensitive strains of the same mating type. Conidia of the arising heterokaryotic mycelia were tested on minimal medium with and without actidione. In these tests resistence of act-1 and -2 mutants was found to be dominant over the sensitivity of the wildtype. However, an analysis of nuclear ratios in the conidial populations by differential plating does not exclude incomplete dominance of act-1.Incorporation of 14-C-leucine into protein of conidia of the wildtype was strongly inhibited by 1 actidione/ml. Resistence in two mutants, representing the two separate genes, was accompanied by a marked decrease of this inhibition. No significant differences in the amount of inhibition were found between the two mutants. It is suggested that cytoplasmic ribosomes may be the cellular components influenced by actidione. In the case of the mutant cells the actidione is no longer effective in this capacity, possibly because of changes in the ribosomal proteins. 相似文献
6.
Summary The behavior of gamete cells ofClosterium ehrenbergii in hypertonic solutions was observed and the significance of changes in osmotic pressure of the protoplasts is discussed in relation to zygote formation. The osmotic pressure of fusing gamete protoplasts was calculated to be 0.063 Osm at the original cell volume. The osmotic pressure of immature gamete protoplasts was 0.24 Osm at incipient plasmolysis. This lowering of cell osmotic pressure may serve to protect the rupture of the plasma membrane during migration of protoplasts in the conjugation tube after dissolution of cell walls. During maturation of gamete cells, chloroplasts and dictyosomes differed greatly in their ultrastructure from those of vegetative cells. These structural changes may be induced by changes of the physiological condition including osmotic pressure in the cells. 相似文献
7.
Development and Characterization of a Nonmorphogenetic Cell Line of Wheat (Triticum aestivum) 总被引:1,自引:1,他引:0
Arron C. Guenzi Kay Scheets J. Larry Green John P. Fellers 《Plant Cell, Tissue and Organ Culture》2004,78(1):23-28
This study was conducted to compare characteristics of a wheat (Triticum aestivum L.) cell line to those of the maize (Zea mays L.) black Mexican sweet (BMS) cell line and to compare protoplasts isolated from suspension cells of these cell lines. The
wheat cell line was established from immature-embryo derived callus of the experimental line ‘ND7532’ and was conditioned
for growth in suspension culture. For both cell lines, measurements of packed cell volume (PCV), fresh weight (FW), and dry
weight (DW) were taken at 3 day intervals from suspension cultures. Measurements of FW of calluses cultured from suspension
cells of both cell lines were taken at 6 day intervals. The morphogenetic potential of the wheat ND7532 cell line was tested
in both callus and suspension cultures using media promoting regeneration and/or organogenesis. Growth rates of ND7532 cells
in suspension culture were comparable to those of BMS cells. However, relative growth rates of calluses recovered from ND7532
suspension cells were slower than those of calluses recovered from BMS suspension cells. The ND7532 cell line has very limited
morphogenetic potential and has been maintained as rapidly growing callus tissue for 11 years. Yields of protoplasts from
suspension cells of the two cell lines were comparable, though ND7532 protoplasts were typically smaller. The wheat cell line
has is now designated ND7532-NM (nonmorphogenetic) and is available for cellular and molecular biology research. 相似文献
8.
Ramassamy S; Olmos E; Bouzayen M; Pech J; latch A 《Journal of experimental botany》1998,49(329):1909-1915
Immunocytological studies have previously shown that
1-aminocyclopropane-1-carboxylate oxidase (ACO), the enzyme which catalyses
the last step of ethylene biosynthesis, is located in the cell wall of
apple and tomato fruit cells. In the present study, a combination of cell
fractionation and immunocytological methods have been used in order to
determine a precise location within this space. Western blotting assays
indicated that more than 70% of ACO antigens of the whole cell are
recovered in freshly prepared protoplasts and that these ACO antigens are
completely removed upon treatment of protoplasts with proteinase K.
Immunocytolabelling showed a periplasmic ACO-antigen signal in protoplasts
which is completely absent in proteinase K-treated protoplasts. Taken
together, these data demonstrate that, in apple fruit, ACO is located at
the external face of the plasma membrane. Possible interactions between the
plasma membrane and ACO activity are discussed.Key
words: ACC oxidase, Malus domestica, apple
fruit protoplasts, plasma membrane, immunocytolocalization.
相似文献
9.
Preparation of protoplasts from Laminaria japonica using native and recombinant abalone alginate lyases 总被引:1,自引:0,他引:1
Laminaria japonica protoplasts were released with high yields using the abalone alginate lyase HdAly in combination with a cellulase and chelating
agents. Addition of EDTA at concentrations higher than 10 mM to Laminaria thalli which had been preincubated with HdAly and Cellulase Onozuka, dramatically improved the yield of protoplasts. EDTA
was far more effective than EGTA, indicating that chelating divalent metal ions such as Mg2+ and Sr2+ in addition to Ca2+ is a key factor for high-yield production of Laminaria protoplasts. Protoplasts had a mean diameter of 27 μm, suggesting that most protoplasts were derived from cortical cells
rather than epidermal layer cells. Recombinant HdAly (rHdAly) was produced from a cDNA clone in the Sf9 insect cell expression
system. rHdAly had substantially the same enzymatic properties and protoplast-producing ability as did native HdAly. The optimal
conditions for high yield production of protoplasts from Laminaria using native and recombinant HdAlys were investigated. 相似文献
10.
Cytological effects of glycine on Bacillus subtilis var. amyloliquefaciens were compared between the cells of the glycine-sensitive parent and resistant mutant. Glycine induced disruption of the protoplasts which had been prepared by treating the glycine-sensitive cells with lysozyme. This effect of glycine was almost completely prevented by preincubating the protoplasts with spermine. The protoplasts prepared from the resistant cells were markedly stable in the presence of glycine. In this mutant, neither cell lysis nor cessation of the enzyme production by glycine occurred, contrary to the results obtained with the glycine-sensitive parent. Between both type of cells little difference could be observed in the metabolic activity for glycine, but free amino acid content was higher in the glycine-resistant cells than in the parent ones. 相似文献
11.
Abdul Ghaffar 《Mycopathologia》1971,45(2):103-107
The effect of some antibiotics onSclerotium cepivorum, the cause of white rot of onion was studied in agar culture and soil. The growth ofS. cepivorum was inhibited in Czapek Dox yeast agar containing 50µg of gliotoxin, viridin, actidione and 100µg of patulin per ml of the medium. Lower concentrations of the antibiotics retarded the growth of the fungus. In soil, patulin had no effect in the control ofS. cepivorum infection of onion seedlings. Concentration of actidione of 5µg/g of soil completely controlled white rot infection but severely stunted the growth of onion seedlings; 40µg/g of actidione killed the seedlings. Despite the importance of actidione as a fungistatic agent its use on onion is limited by its phytotoxicity. 相似文献
12.
Summary A method is described for isolating mesophyll protoplasts from leaves and secretory cell protoplasts from salt glands of the facultative halophyte, Ceratostigma plumbaginoides (L.). Rates of ATP hydrolysis in both cell types were determined, and levels in secretory cell protoplast preparations were fourfold higher than those in mesophyll protoplast preparations, based on total protein. The rate of ATP hydrolysis was sensitive to azide and vanadate, and stimulated by Triton-X-100. Additionally, immunoblot procedures using an antibody to the plasma membrane H+/ATPase was used to compare ATPase levels of the mesophyll and secretory cell protoplasts. Results indicate that secretory cells have a higher concentration of H+/ATPase than mesophyll cells, consistent with their putative function in salt glands.Abbreviations ATP
adenosine triphosphate
- BSA
bovine serum albumin
- DIDS
diisothiocyano-2,2'-disulfonic acid stilbene
- DNP
dinitrophenol
- DTT
dithiothreitol
- FITC
fluorescein isothiocyanate
- NAD+/NADH
nicotinamide adenine dinucleotide
- SDS
sodium dodecylsulfate 相似文献
13.
Cortical microtubules (MTs) in protoplasts prepared from tobacco (Nicotiana tabacum L.) BY-2 cells were found to be sensitive to cold. However, as the protoplasts regenerated cell walls they became resistant
to cold, indicating that the cell wall stabilizes cortical MTs against the effects of cold. Since poly-l-lysine was found to stabilize MTs in protoplasts, we examined extensin, an important polycationic component of the cell wall,
and found it also to be effective in stabilizing the MTs of protoplasts. Both extensin isolated from culture filtrates of
tobacco BY-2 cells and extensin isolated in a similar way from cultures of tobacco XD-6S cells rendered the cortical MTs in
protoplasts resistant to cold. Extensin at 0.1 mg·ml−1 was as effective as the cell wall in this respect. It is probable that extensin in the cell wall plays an important role
in stabilizing cortical MTs in tobacco BY-2 cells. 相似文献
14.
15.
Summary A convenient and rapid isolation procedure for root cell protoplasts suitable for patch clamp experiments, was developed for root cells of tomato (Lycopersicon esculentum) andPlantago species, grown on hydroculture. The procedure is based on a minimal exposure of cells to cell wall degrading enzyme mixtures. After an incubation period of 30 min in a cell wall degrading enzyme mixture all free floating cells were discarded. Subsequently the root material was rinsed and a second group of cells, still present inside the tissue, was freed by application of mechanical pressure. The newly released protoplasts were filtered and collected on the glass bottom of a patch clamp dish. The bathing medium was rinsed extensively removing cellulose fibrils and protoplasts not attached to the glass. Removal of these cellulose fibrils significantly improved the seal success ratio. The isolated protoplasts were suitable for patch clamp experiments in the cell-attached patch, the whole cell and the isolated patch configuration.Abbreviations BSA
bovine serum albumin
- BTP
bis-tris propane
- CAP
cell-attached patch
- OOP
outside out patch
- PEG
polyethylene glycol
- WC
whole cell 相似文献
16.
N. E. Nyange B. Williamson G. D. Lyon R. J. McNicol T. Connolly 《Plant cell reports》1997,16(11):763-769
Hypocotyl-derived calli of genotypes and segregating populations of Coffea arabica, differing in susceptibility to Colletotrichum kahawae, were used to produce cell suspensions and protoplasts which were exposed to partially purified culture filtrates (PPCFs)
prepared from the pathogen. The growth and viability of PPCF-treated cells and protoplasts were measured using packed cell
volume, fluorescein diacetate staining and a colorimetric assay involving the tetrazolium salt MTT. Differential responses
of cells and protoplasts were influenced by genotype, time of exposure and PPCF concentration. Protoplasts of resistant genotypes
responded differentially from more susceptible genotypes as early as 4 h after challenge with the phytotoxin, suggesting that
they were more sensitive than cell suspensions to the treatments. Protoplasts exposed to PPCFs from C. kahawae may therefore be used to screen and select genotypes resistant to, or tolerant of, coffee berry disease.
Received: 10 April 1996 / Revision received: 25 August 1996 / Accepted: 15 September 1996 相似文献
17.
A. R. Gould S. E. Ashmore 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1982,64(1):7-12
Summary The polycation mediated attachment of purified tritiated DNA to plant protoplasts has been measured by quantitative microautoradiography. The automated grain counting technique used, also provides information on the cell cycle stage of individual protoplasts, which circumvents the need to synchronize the plant cell population before preparation of protoplasts. With protoplasts from asynchronously dividing suspension cultures of Nicotiana syhestris (NS-1), S-phase protoplasts appear to be inefficient binders of 3H-DNA, as compared with G1 or G2 protoplasts. Protoplasts derived from a tumour line of Crepis capillaris (CAPT) exhibit 3H-DNA binding at all cell cycle phases, but Sphase protoplasts appear to be preferential binders. These differences are discussed with reference to cell cycle kinetics, membrane charge variation and the possibility of increasing the efficiency of genetic transformation of higher plant cells in culture. 相似文献
18.
A method for high-frequency intergeneric fusion of plant protoplasts 总被引:13,自引:2,他引:11
Summary Protoplasts of Vicia hajastana Grossh. obtained from suspension-culture cells and Pisum sativum L. obtained from leaves adhered tightly to each other in concentrated solutions of high-molecular-weight polyethylene glycol (PEG). The adhesion occurred non-specifically between the free protoplasts from the same species as well as from the different species and genus. It was enhanced by enrichment of the PEG solution with calcium. Very few heteroplasmic fusions occurred during the period when the protoplasts were incubated in the PEG solution. However, many heterokaryons (up to 10%) were formed soon after the PEG solution was diluted out. The same phenomena were also observed in protoplasts from suspension-culture cells of Glycine max L. and from leaves of Hordeum vulgare L. Vicia and soybean protoplasts obtained from cultured cells regenerated cell walls and underwent sustained cell division after such treatment. Some Vicia-pea heterokaryons divided once. Over 10% of the soybean-barley hybrids divided in 7 days. Some divided 4–5 times and formed small clusters of cells in 10 days. The hybrids were recognizable because they contained chloroplasts from the leaf protoplast and exhibited morphological characters typical of the chlorophyll-less cells. None of the protoplasts from pea and barley leaves, either with or without PEG treatment, underwent cell division during the period of observation. The mechanism of adhesion and fusion of the protoplasts has been discussed.National Research Council (Canada) No. 13732. 相似文献
19.
Eva Kot Robin Miller-Catchpole Anatoly Bezkorovainy 《Biological trace element research》1993,38(1):1-12
Protoplasts ofBifidobacterium thermophilum were prepared by a combination of lysozyme and protease digestion, and ferrous iron uptake studies were carried out. Little,
if any, iron was internalized by the protoplasts, although large amounts of iron were bound to the protoplast surface. This
binding was much greater than that of intact cells, which prefer to internalize iron by an energy-dependent process. It was
also found that the binding of iron by protoplasts of cells grown in an iron-deficient medium was much more extensive than
that of cells grown in an iron-sufficient medium. Soluble and particulate fractions of protoplasts were prepared by grinding
them in a glass homogenizer, and the particulate fraction was also subjected to iron binding studies. The amount of iron bound
was the same as that in intact protoplasts, indicating that the particulate fraction membrane fragments bound iron on their
outer surface only. Nevertheless, when iron-preloaded cells were protoplasted and their surface cleared of iron, their particulate
fraction contained considerable amounts of iron, indicating that the inner surface of the membranes is capable of binding
iron as long as the cell is intact. The amount of iron so bound was dose-dependent on the amount of iron entering the cell.
The failure of the outer and inner surface iron pools to mix was confirmed by the fact that when iron-preloaded protoplasts
were incubated with additional iron, only the latter (surface-bound) was elutable with nonradioactive 2 mM FeSO4. It is concluded that increasing bifidobacterial iron load increases the amount of iron bound to the inner surface of the
membrane; the procedure, which is effective in forming bifidobacterial protoplasts, destroys their iron transport mechanism
while uncovering surface iron-binding sites; and that such iron-binding sites may be of significance in the cellular iron
metabolism processes. 相似文献
20.
Vladan Ondřej Miloslav Kitner Ivana Doležalová Petr Nádvorník Božena Navrátilová Aleš Lebeda 《Molecules and cells》2009,27(4):443-447
This paper reports on the structural rearrangement of satellite DNA type I repeats and heterochromatin during the dedifferentiation
and cell cycling of mesophyll protoplasts of cucumber (Cucumis sativus). These repeats were localized in the telomeric heterochromatin of cucumber chromosomes and in the chromocenters of interphase
nuclei. The dramatic reduction of heterochromatin involves decondensation of subtelomeric repeats in freshly isolated protoplasts;
however, there are not a great many remarkable changes in the expression profile. In spite of that, reformation of the chromocenters,
occurring 48 h after protoplast isolation, is accompanied by recondensation of satellite DNA type I; however, only partial
reassembly of these repeats was revealed. In this study, FISH and a flow cytometry assay show a correlation between the partial
chromocenter and the repeats reassembly, and with the reentry of cultivated protoplasts into the cell cycle and first cell
division. After that, divided cells displayed a higher variability in the expression profile than did leaves’ mesophyll cells
and protoplasts. 相似文献