Purificationof plasma membranes from different cell types of Zygosaccharomyces bailii

Synemin, a high-molecular-weight protein associated with intermediate filaments in muscle, and vimentin, an intermediate-filament subunit found in many different cell types, have been identified by immunologic and electrophoretic criteria as components of intermediate filaments in mature avian erythrocytes. Desmin, the predominant subunit of intermediate filaments in muscle, has not been detected in these cells. Two dimensional immunoautoradiography of proteolytic fragments of synemin and vimentin demonstates that the erythrocyte proteins are highly homologous, if not identical, to their muscle counterparts. Double immunoflurorescence reaveals that erythrocyte synemin and vimentin co-localize in a cytoplasmic network of sinuous filaments that extends from the nucleus to the plasma membrane and resists aggregation by colcemid. Erythrocytes that are attached to glass cover slips can be sonicated to remove nuclei and nonadherent regions of the plasma membrane; this leaves elliptical patches of adherent membrane that retain mats of vimentin- and synemin-containing intermediate filaments, as seen by immunofluorescence and rotary shadowing. Similarly, mechanical enucleation of erythrocyte ghosts in suspension allows isolation of plasma membranes that retain a significant fraction of the synemin and vimentin, as assayed by electrophoresis, and intermediate filaments, as seen in thin sections. Both synemin and vimentin remain insoluble along with spectrin and actin, in solutions containing nonionic detergent and high salt. However, brief exposure of isolated membrane to distilled water releases the synemin and vimentin together in nearly pure form, before the release of significant amounts of spectrin and actin. These data suggest that avian erythrocyte intermeditate filaments are somehow anchored to the plasma membrane; erythrocytes may thus provide a simple system for the study of intermediate filaments and their mode of interaction with membranes. In addition, these data, in conjunction with previous data from muscle, indicate that synemin is capable of associating with either desmin or vimentin and may thus perform a special role in the structure or function of intermediate filaments in erythrocytes as well as muscle.

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Ultrastructural features of the gut of Sitophilus granarius (L.) (Coleoptera: Curculionidae) with notes on distribution of proteinases and amylases in crop and midgut

Canadian Journal of Zoology ◽

10.1139/z84-181 ◽

1984 ◽

Vol 62 (7) ◽

pp. 1251-1259 ◽

Cited By ~ 36

Author(s):

J. E. Baker ◽

S. M. Woo ◽

R. V. Byrd

Keyword(s):

Plasma Membranes ◽

Cell Types ◽

Sitophilus Granarius ◽

Posterior Midgut ◽

Functional Differences ◽

Basal Plasma ◽

Dark Staining ◽

Different Cell Types ◽

Columnar Cells ◽

Anterior Midgut

In addition to typical columnar cells, dark-staining cells characterized by deep invaginations of basal plasma membranes were found throughout the midgut of adult Sitophilus granarius (L.). These invaginations formed intracellular channels that extended to the perinuclear region and indicated an involvement of these cells in secretion and (or) absorption. Cells with large vacuolelike structures that occasionally filled the entire supranuclear region were found in the anterior midgut, while multicellular crypts and cells that formed apical extrusions into the lumen were common in the posterior midgut. Fine structure of gastric caeca indicated functional differences between those located in anterior and posterior midgut regions. Numerous dark-staining granules were found in apical regions of cells of the anterior caeca, whereas elongated mitochondria were found in microvilli that made up the brush border of posterior caecal cells. Thus, although the midgut is not obviously differentiated into zones, there are different cell types in different regions of the gut involved in digestive and nutrient absorption processes. Evidence indicated that amylase in S. granarius is secreted by salivary glands whereas trypsin and aminopeptidase are secreted by midgut. A slow, continuous secretion of amylase occurs whereas proteinases are secreted in response to ingested food.

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Microwave fixation improves antigenicity of glutaraldehyde-sensitive antigens while preserving ultrastructural detail.

Journal of Histochemistry & Cytochemistry ◽

10.1177/43.3.7868860 ◽

1995 ◽

Vol 43 (3) ◽

pp. 307-311 ◽

Cited By ~ 24

Author(s):

M C Jamur ◽

C D Faraco ◽

L O Lunardi ◽

R P Siraganian ◽

C Oliver

Keyword(s):

Bone Marrow ◽

Mast Cells ◽

Plasma Membranes ◽

Cell Types ◽

Cell Plasma ◽

Morphological Detail ◽

Strong Staining ◽

Microwave Fixation ◽

Different Cell Types ◽

Rat Mast Cells

Microwave fixation for electron microscopy has been used primarily for post-embedding immunocytochemistry. The present study examined the ability of microwave fixation to preserve the antigenicity of glutaraldehyde-sensitive antigens for pre-embedding immunocytochemistry. Five monoclonal antibodies (MAbs) directed against cell surface components of rat mast cells were tested. The MAbs failed to show any labeling of conventionally fixed rat bone marrow-derived mast cells even at glutaraldehyde concentrations as low as 0.1%. Strong staining of mast cell plasma membranes was seen when bone marrow was initially fixed with 2% formaldehyde and then refixed in 2% glutaraldehyde/2% formaldehyde after immunostaining. However, the ultrastructural preservation of the cells was poor. Antigenicity and morphological detail were both preserved when bone marrow was fixed in 0.05% glutaraldehyde/2% formaldehyde for 4 sec in a 550-W microwave oven. With this method, mast cells in various stages of maturation as well as cells that did not contain granules were immunoreactive. This method should prove useful with antigens from many different cell types that are sensitive to glutaraldehyde fixation.

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Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053310 ◽

1982 ◽

Vol 40 ◽

pp. 118-119

Author(s):

U. Aebi ◽

P. Rew ◽

T.-T. Sun

Keyword(s):

Electron Microscopy ◽

Structural Organization ◽

Cell Types ◽

Structural Features ◽

Molecular Architecture ◽

The Past ◽

Keratin Filaments ◽

Different Types ◽

10 Nm Filaments ◽

Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

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Membrane microdomains: lessons from microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140257 ◽

1995 ◽

Vol 53 ◽

pp. 776-777

Author(s):

J.M. Robinson ◽

J.M Oliver

Keyword(s):

Spatial Distribution ◽

Plasma Membrane ◽

Epithelial Cells ◽

Plasma Membranes ◽

Cell Types ◽

Imaging Modalities ◽

Membrane Microdomains ◽

Membrane Domains ◽

Lateral Heterogeneity ◽

Functional Importance

Specialized regions of plasma membranes displaying lateral heterogeneity are the focus of this Symposium. Specialized membrane domains are known for certain cell types such as differentiated epithelial cells where lateral heterogeneity in lipids and proteins exists between the apical and basolateral portions of the plasma membrane. Lateral heterogeneity and the presence of microdomains in membranes that are uniform in appearance have been more difficult to establish. Nonetheless a number of studies have provided evidence for membrane microdomains and indicated a functional importance for these structures.This symposium will focus on the use of various imaging modalities and related approaches to define membrane microdomains in a number of cell types. The importance of existing as well as emerging imaging technologies for use in the elucidation of membrane microdomains will be highlighted. The organization of membrane microdomains in terms of dimensions and spatial distribution is of considerable interest and will be addressed in this Symposium.

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Processing and Characterization of Recombinant von Willebrand Factor Expressed in Different Cell Types Using a Vaccinia Virus Vector

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648398 ◽

1992 ◽

Vol 67 (01) ◽

pp. 154-160 ◽

Cited By ~ 14

Author(s):

P Meulien ◽

M Nishino ◽

C Mazurier ◽

K Dott ◽

G Piétu ◽

...

Keyword(s):

Vaccinia Virus ◽

Von Willebrand Factor ◽

Human Fibroblasts ◽

Active Form ◽

Cell Types ◽

Biologically Active ◽

L Cells ◽

Von Willebrand ◽

Different Cell Types ◽

Willebrand Factor

SummaryThe cloning of the cDNA encoding von Willebrand factor (vWF) has revealed that it is synthesized as a large precursor (pre-pro-vWF) molecule and it is now clear that the prosequence or vWAgll is responsible for the intracellular multimerization of vWF. We have cloned the complete vWF cDNA and expressed it using a recombinant vaccinia virus as vector. We have characterized the structure and function of the recombinant vWF (rvWF) secreted from five different cell types: baby hamster kidney (BHK), Chinese hamster ovary (CHO), human fibroblasts (143B), mouse fibroblasts (L) and primary embryonic chicken cells. Forty-eight hours after infection, the quantity of vWF antigen found in the cell supernatant varied from 3 to 12 U/dl depending on the cell type. By SDS-agarose gel electrophoresis, the percentage of high molecular weight forms of vWF varied from 39 to 49% relative to normal plasma for BHK, CHO, 143B and chicken cells but was less than 10% for L cells. In all cell types, the two anodic subbands of each multimer were missing. The two cathodic subbands were easily detected only in BHK and L cells. By SDS-PAGE of reduced samples, pro-vWF was present in similar quantity to the fully processed vWF subunit in L cells, present in moderate amounts in BHK and CHO and in very low amounts in 143B and chicken cells. rvWF from all cells bound to collagen and to platelets in the presence of ristocetin, the latter showing a high correlation between binding efficiency and degree of multimerization. rvWF from all cells was also shown to bind to purified FVIII and in this case binding appeared to be independent of the degree of multimerization. We conclude that whereas vWF is naturally synthesized only by endothelial cells and megakaryocytes, it can be expressed in a biologically active form from various other cell types.

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Role of Transcriptional Read-Through in PRE Activity in Drosophila melanogaster

Acta Naturae ◽

10.32607/20758251-2016-8-2-79-86 ◽

2016 ◽

Vol 8 (2) ◽

pp. 79-86 ◽

Cited By ~ 3

Author(s):

P. V. Elizar’ev ◽

D. V. Lomaev ◽

D. A. Chetverina ◽

P. G. Georgiev ◽

M. M. Erokhin

Keyword(s):

Dna Sequences ◽

Cell Types ◽

Transcription Terminator ◽

Response Elements ◽

Polycomb Response Elements ◽

The Individual ◽

Multicellular Organisms ◽

Different Cell Types ◽

Main Factor

Maintenance of the individual patterns of gene expression in different cell types is required for the differentiation and development of multicellular organisms. Expression of many genes is controlled by Polycomb (PcG) and Trithorax (TrxG) group proteins that act through association with chromatin. PcG/TrxG are assembled on the DNA sequences termed PREs (Polycomb Response Elements), the activity of which can be modulated and switched from repression to activation. In this study, we analyzed the influence of transcriptional read-through on PRE activity switch mediated by the yeast activator GAL4. We show that a transcription terminator inserted between the promoter and PRE doesnt prevent switching of PRE activity from repression to activation. We demonstrate that, independently of PRE orientation, high levels of transcription fail to dislodge PcG/TrxG proteins from PRE in the absence of a terminator. Thus, transcription is not the main factor required for PRE activity switch.

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MAPK: A Key Player in the Development and Progression of Stroke

CNS & Neurological Disorders - Drug Targets ◽

10.2174/1871527319666200613223018 ◽

2020 ◽

Vol 19 (4) ◽

pp. 248-256

Author(s):

Yangmin Zheng ◽

Ziping Han ◽

Haiping Zhao ◽

Yumin Luo

Keyword(s):

Ischemic Stroke ◽

Signaling Pathway ◽

Complex Disease ◽

Therapeutic Targets ◽

Cell Types ◽

Mapk Signaling ◽

Mapk Signaling Pathway ◽

Effective Prevention ◽

Prevention And Treatment ◽

Different Cell Types

Conclusion: Stroke is a complex disease caused by genetic and environmental factors, and its etiological mechanism has not been fully clarified yet, which brings great challenges to its effective prevention and treatment. MAPK signaling pathway regulates gene expression of eukaryotic cells and basic cellular processes such as cell proliferation, differentiation, migration, metabolism and apoptosis, which are considered as therapeutic targets for many diseases. Up to now, mounting evidence has shown that MAPK signaling pathway is involved in the pathogenesis and development of ischemic stroke. However, the upstream kinase and downstream kinase of MAPK signaling pathway are complex and the influencing factors are numerous, the exact role of MAPK signaling pathway in the pathogenesis of ischemic stroke has not been fully elucidated. MAPK signaling molecules in different cell types in the brain respond variously after stroke injury, therefore, the present review article is committed to summarizing the pathological process of different cell types participating in stroke, discussed the mechanism of MAPK participating in stroke. We further elucidated that MAPK signaling pathway molecules can be used as therapeutic targets for stroke, thus promoting the prevention and treatment of stroke.

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Special Issue: “Bacteriophages and Biofilms”

Viruses ◽

10.3390/v13020257 ◽

2021 ◽

Vol 13 (2) ◽

pp. 257

Author(s):

Zuzanna Drulis-Kawa ◽

Barbara Maciejewska

Keyword(s):

Cell Types ◽

Special Issue ◽

Different Cell Types

Biofilms are a community of surface-associated microorganisms characterized by the presence of different cell types in terms of physiology and phenotype [...]

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In situ differentiation of iridophore crystallotypes underlies zebrafish stripe patterning

Nature Communications ◽

10.1038/s41467-020-20088-1 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Dvir Gur ◽

Emily J. Bain ◽

Kory R. Johnson ◽

Andy J. Aman ◽

H. Amalia Pasoili ◽

...

Keyword(s):

Skin Color ◽

Cell Types ◽

Color Pattern ◽

Single Type ◽

Sequencing Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Cryogenic Scanning Electron Microscopy ◽

Different Cell Types

AbstractSkin color patterns are ubiquitous in nature, impact social behavior, predator avoidance, and protection from ultraviolet irradiation. A leading model system for vertebrate skin patterning is the zebrafish; its alternating blue stripes and yellow interstripes depend on light-reflecting cells called iridophores. It was suggested that the zebrafish’s color pattern arises from a single type of iridophore migrating differentially to stripes and interstripes. However, here we find that iridophores do not migrate between stripes and interstripes but instead differentiate and proliferate in-place, based on their micro-environment. RNA-sequencing analysis further reveals that stripe and interstripe iridophores have different transcriptomic states, while cryogenic-scanning-electron-microscopy and micro-X-ray diffraction identify different crystal-arrays architectures, indicating that stripe and interstripe iridophores are different cell types. Based on these results, we present an alternative model of skin patterning in zebrafish in which distinct iridophore crystallotypes containing specialized, physiologically responsive, organelles arise in stripe and interstripe by in-situ differentiation.

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