The ultrastructural localization of 60-kDa Ro protein and human cytoplasmic RNAs: Association with novel electron-dense bodies

We have recently described the ultrastructural localization of NADPase activity in the exocrine pancreas of rat. The enzyme was found in the intermediate saccules of the Golgi apparatus, in dense bodies and lysosomes but was absent from zymogen granules. A very intense reaction was noticed in a peculiar structure which was termed “Snake-Like Tubule” (SLT). The purposes of the present study were firstly to delineate SLT distribution in the acinar cell and secondly to define any possible relationship or association with other cellular organelles.NADPase cytochemical reaction was performed on the pancreas of adult Sprague Dawley rats. Small lobules were excised and fixed for 50 min, at 4°C, in 2% glutaraldehyde buffered with 0.1M cacodylate at pH 7.2. Lobules were rinsed several times with the same buffer containing 570 sucrose and cut with a Mcllwayn tissue chopper. Sections were washed several times with buffer and incubated for 2 hr at 37°C in the following medium: 4mM NADPH; 40mM sodium acetate buffer, pH 5.0; 4mM lead acetate and 5% sucrose.

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ULTRASTRUCTURAL LOCALIZATION OF ACID MUCOSUBSTANCE AND ANTIMONATE-PRECIPITABLE CATION IN HUMAN AND RABBIT PLATELETS AND MEGAKARYOCYTES

Journal of Histochemistry & Cytochemistry ◽

10.1177/17.12.781 ◽

1969 ◽

Vol 17 (12) ◽

pp. 781-792 ◽

Cited By ~ 24

Author(s):

S. S. SPICER ◽

W. B. GREENE ◽

J. H. HARDIN

Keyword(s):

Bone Marrow ◽

Osmium Tetroxide ◽

Plasma Membranes ◽

Ultrastructural Localization ◽

Human Platelets ◽

Buffy Coat ◽

Cytoplasmic Granules ◽

Dense Bodies ◽

Osmium Tetroxide Solution ◽

Potassium Pyroantimonate

For selective ultrastructural localization of acid mucosubstance in rabbit and human platelets and megakaryocytes, bone marrow and buffy coat specimens were fixed with formalin, glutaraldehyde or osmium tetroxide, sectioned at 40 µ and stained with the Rinehart-Abul-Haj solution of dialyzed iron. In specimens from both rabbit and man, dialyzed iron staining was observed within nucleoids of the cytoplasmic granules (α-granulomeres) of platelets and megakaryocytes, on the outer surface of the plasma membranes of platelets and megakaryocytes and on the luminal surface of demarcation membranes of megakaryocytes. These results were obtained following any of the three fixation procedures, except when nucleoids failed to stain after glutaraldehyde fixation. For ultrastructural localization of pyroantimonate-precipitable cation, bone marrow and buffy coat specimens were fixed in Komnick's solution of potassium pyroantimonate and osmium tetroxide. In specimens from both species, antimonate deposits were localized within the dense bodies (5-hydroxytryptamine organelles) of platelets and within nucleoids of cytoplasmic granules of platelets and megakaryocytes. The dense bodies were well preserved in platelets fixed in a pyrophosphate-osmium tetroxide solution but were poorly, if at all, preserved by osmium tetroxide solutions containing other buffers.

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Ultrastructural localization of nicotinamide adenine dinucleotide phosphatase (NADPase) activity to the intermediate saccules of the Golgi apparatus in rat incisor ameloblasts.

Journal of Histochemistry & Cytochemistry ◽

10.1177/28.1.7351472 ◽

1980 ◽

Vol 28 (1) ◽

pp. 16-26 ◽

Cited By ~ 39

Author(s):

C E Smith

Keyword(s):

Golgi Apparatus ◽

Nicotinamide Adenine Dinucleotide ◽

Secretory Granules ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Ultrastructural Localization ◽

Nicotinamide Adenine ◽

General Phenomenon ◽

Rat Incisor ◽

Selective Staining ◽

Dense Bodies

Cytochemical evidence for the existence of a Golgi-associated phosphatase activity that hydrolyzes nicotinamide adenine dinucleotide phosphate (NADP) at acid pH in rat incisor ameloblasts was obtained by incubating sections from glutaraldehyde-fixed teeth in a medium containing NADP as substrate and lead ions as capture agent. Following incubation for 1 hr at 37 degrees C and pH 5.0, the Golgi saccules situated between those at the cis (immature) and trans (mature) faces of the ameloblast Golgi apparatus were marked by reaction product with the heaviest deposit in the middle saccule. Reaction product was otherwise seen in trace amounts only over some elements of the GERL system as well as a few lysosomal dense bodies and immature secretory granules. Control experiments established that the selective staining of intermediate Golgi saccules at pH 5.0 could only be duplicated by using substrates that resembled the complete NADP molecule, and not just the portion containing the adenosine 2'-monophosphate group. As well, no deposits of reaction product were seen within the Golgi saccules of ameloblasts incubated at pH 5.0 with nictoinamide adenine dinucleotide (NAD) as the substrate or that were incubated at pH 7.2 or pH 9.0 with NADP as the substrate. It was concluded that a specific, acid-NADPase activity is present in the intermediate Golgi saccules of secretory ameloblasts. Preliminary observations on other cells suggest that the localization of NADPase activity to Golgi saccules may constitute a general phenomenon.

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Ultrastructural localization of coenzyme A phosphatase (CoA-Pase) activity to the GERL system in secretory ameloblasts of the rat incisor.

Journal of Histochemistry & Cytochemistry ◽

10.1177/29.11.6172461 ◽

1981 ◽

Vol 29 (11) ◽

pp. 1243-1254 ◽

Cited By ~ 7

Author(s):

C E Smith

Keyword(s):

Endoplasmic Reticulum ◽

Coenzyme A ◽

Secretory Granules ◽

Ultrastructural Localization ◽

Rat Incisor ◽

Acetyl Coa ◽

Selective Staining ◽

Dense Bodies ◽

Low Concentrations ◽

Hydrolysis Of

Enzymatic hydrolysis of the monoester phosphate group from coenzyme A (CoA) was studied in rat incisor ameloblasts by incubating specimens from glutaraldehyde-fixed teeth in a cytochemical medium prepared with acetyl-CoA as substrate and lead ions as capture agent for phosphate. Ameloblasts incubated for 1 hr at 37 degrees C and at pH 5.0 in this medium showed reaction product localized almost exclusively along the trans (mature) aspect of the Golgi apparatus within a network of small granules and interconnecting tubular channels that comprise the GERL system in this cell. Reaction product was otherwise seen in trace amounts only within some Golgi saccules, a few lysosomal dense bodies and, in rare instances, within an occasional focal area of the endoplasmic reticulum. No selective staining of the GERL system was seen in control ameloblasts incubated at either pH 7.2 or pH 9.0 with acetyl-CoA as substrate, or incubated at pH 5.0 with dephospho-CoA as substrate. Control experiments at pH 5.0 also revealed that reaction product selectively stained the GERL system in ameloblasts when other molecules resembling CoA were used as substrate (e.g., crotonyl-CoA, 3'-NADP+), but not when adenosine 3'-monophosphate (3'-AMP) was used as substrate. That is, ameloblasts incubated at pH 5.0 with 3'-AMP showed heavy deposits of reaction product at many sites throughout the cell, including most lysosomal dense bodies, the Golgi saccules, the GERL system, most secretory granules, the nucleus, and extensively throughout the endoplasmic reticulum. These findings suggest that the GERL system of ameloblasts contains a CoA-specific phosphatase activity that may function to convert CoA to dephospho-CoA at acid pH. Biochemical studies included with this investigation further indicate that CoA-Pase activity saturates at exceptionally low concentrations of substrate (KM = 30 microM CoA) compared to other acid-dependent phosphatases.

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Immunoelectron microscope studies of membrane-microfilament interactions: distributions of alpha-actinin, tropomyosin, and vinculin in intestinal epithelial brush border and chicken gizzard smooth muscle cells.

The Journal of Cell Biology ◽

10.1083/jcb.91.3.614 ◽

1981 ◽

Vol 91 (3) ◽

pp. 614-628 ◽

Cited By ~ 247

Author(s):

B Geiger ◽

A H Dutton ◽

K T Tokuyasu ◽

S J Singer

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Brush Border ◽

Muscle Cells ◽

Ultrastructural Localization ◽

Cytoskeletal Proteins ◽

Junctional Complex ◽

Intestinal Epithelial ◽

Chicken Gizzard ◽

Dense Bodies

The ultrastructural localization of three cytoskeletal proteins, alpha-actinin, tropomyosin, and vinculin, in the brush border of epithelial cells of chicken small intestine and the smooth muscle cells of chicken gizzard was studied by immunofluorescence and immunonelectron microscope labeling of frozen sections of lightly fixed, intact tissues. In the immunoelectron microscope studies, a recently described new type of electron-dense antibody conjugate, imposil-antibody, has been successfully used, along with ferritin-antibody conjugates, in single and double immunolabeling experiments. In the intestinal brush border shows that vinvulin is sharply confined to the junctional complex close to the membrane region of the zonula adherens, in distinct contrast to the more diffuse distributions of the other two proteins. In the smooth muscle cells, the labeling patterns show that vinculin is sharply confined to the membrane-associated dense plaques, closer to the membrane than the alpha-Actinin is also present in the cytoplastic dense bodies, from which vinculin is absent. Tropomyosin is present diffusely distributed in the cytoplasm, but absent from both dense plaques and dense bodies. These findings with the muscle cells demonstrate, therefore, that the dense plaques and dense bodies are chemically and structurally distinct entities. The results with both tissues, along with those in previous papers (Geiger, 1979, Cell. 18:193-205.; Geiger et al., 1980, Proc. Natl. Acad. Sci. U. S. A. 77:4127-4131), suggest that vinculin may play an important and widespread role in the linkage of actin-containing microfilament bundles to membranes.

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Ultrastructural localization of specific nucleoprotein fractions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081887 ◽

1978 ◽

Vol 36 (2) ◽

pp. 204-205

Author(s):

G. L. Brown

Keyword(s):

Gel Electrophoresis ◽

Mouse Liver ◽

Polyacrylamide Gel Electrophoresis ◽

Ultrastructural Localization ◽

Polyacrylamide Gel ◽

Acid Extraction ◽

Acid Solutions ◽

Low Salt ◽

Liver Nuclei ◽

Phosphate Groups

Bismuth (Bi) stains nucleoproteins (NPs) by interacting with available amino and primary phosphate groups. These two staining mechanisms are distinguishable by glutaraldehyde crosslinking (Fig. 1,2).Isolated mouse liver nuclei, extracted with salt and acid solutions, fixed in either formaldehyde (form.) or gl utaraldehyde (glut.) and stained with Bi, were viewed to determine the effect of the extractions on Bi stainina. Solubilized NPs were analyzed by SDS-polyacrylamide gel electrophoresis.Extraction with 0.14 M salt does not change the Bi staining characteristics (Fig. 3). 0.34 M salt reduces nucleolar (Nu) staining but has no effect on interchromatinic (IC) staining (Fig. 4). Proteins responsible for Nu and glut.- insensitive IC staining are removed when nuclei are extracted with 0.6 M salt (Fig. 5, 6). Low salt and acid extraction prevents Bi-Nu staining but has no effect on IC staining (Fig. 7). When nuclei are extracted with 0.6 M salt followed by low salt and acid, all Bi-staining components are removed (Fig. 8).

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Ultrastructural Localization of Acid Mucosubstance in Skeletal Muscle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060271 ◽

1967 ◽

Vol 25 ◽

pp. 52-53 ◽

Cited By ~ 2

Author(s):

William J. Dougherty ◽

Samuel S. Spicer

Keyword(s):

Striated Muscle ◽

Divalent Cations ◽

Ultrastructural Localization ◽

Major Elements ◽

Frozen Sections ◽

Thorium Dioxide ◽

Iron Solution ◽

Coupling System ◽

Psoas Muscles ◽

Formalin Fixed

In recent years, considerable attention has focused on the morphological nature of the excitation-contraction coupling system of striated muscle. Since the study of Porter and Palade, it has become evident that the sarcoplastic reticulum (SR) and transverse tubules constitute the major elements of this system. The problem still exists, however, of determining the mechamisms by which the signal to interdigitate is presented to the thick and thin myofilaments. This problem appears to center on the movement of Ca++ions between myofilaments and SR. Recently, Philpott and Goldstein reported acid mucosubstance associated with the SR of fish branchial muscle using the colloidal thorium dioxide technique, and suggested that this material may serve to bind or release divalent cations such as Ca++. In the present study, Hale's iron solution adapted to electron microscopy was applied to formalin-fixed myofibrils isolated from glycerol-extracted rabbit psoas muscles and to frozen sections of formalin-fixed rat psoas muscles.

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Immunoenzymatic demonstration of the simultaneous presence of transferrin, hemopexin and albumin in a same hepatocyte and their ultrastructural localization

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081309 ◽

1978 ◽

Vol 36 (2) ◽

pp. 88-89

Author(s):

M. Kraemer ◽

J. Foucrier ◽

J. Vassy ◽

M.T. Chalumeau

Keyword(s):

Plasma Proteins ◽

Rat Hepatocytes ◽

Ultrastructural Localization ◽

Carrier Proteins ◽

Normal Cells ◽

Adult Rat ◽

Adult Rat Hepatocytes ◽

Monospecific Antisera ◽

Different Levels

Some authors using immunofluorescent techniques had already suggested that some hepatocytes are able to synthetize several plasma proteins. In vitro studies on normal cells or on cells issued of murine hepatomas raise the same conclusion. These works could be indications of an hepatocyte functionnal non-specialization, meanwhile the authors never give direct topographic proofs suitable with this hypothesis.The use of immunoenzymatic techniques after obtention of monospecific antisera had seemed to us useful to bring forward a better knowledge of this problem. We have studied three carrier proteins (transferrin = Tf, hemopexin = Hx, albumin = Alb) operating at different levels in iron metabolism by demonstrating and localizing the adult rat hepatocytes involved in their synthesis.Immunological, histological and ultrastructural methods have been described in a previous work.

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Ultrastructural Localization of Acetylcholinesterase in the Arcuate Nucleus and Median Eminence of the Rat

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079644 ◽

1977 ◽

Vol 35 ◽

pp. 440-441

Author(s):

K.A. Carson ◽

C.B. Nemeroff ◽

M.S. Rone ◽

J.S. Kizer ◽

J.S. Hanker

Keyword(s):

Choline Acetyltransferase ◽

Median Eminence ◽

Arcuate Nucleus ◽

Cholinergic Neurons ◽

Ultrastructural Localization ◽

Male Rats ◽

Neonatal Rats ◽

Good Marker ◽

Chemical Studies ◽

High Doses

Biochemical, physiological, pharmacological, and more recently enzyme histo- chemical data have indicated that cholinergic circuits exist in the hypothalamus. Ultrastructural correlates of these pathways such as acetylcholinesterase (AchE) positive neurons in the arcuate nucleus (ARC) and stained terminals in the median eminence (ME) have yet to be described. Initial studies in our laboratories utilizing chemical lesioning and microdissection techniques coupled with microchemical and light microscopic enzyme histo- chemical studies suggested the existence of cholinergic neurons in the ARC which project to the ME (1). Furthermore, in adult male rats with Halasz deafferentations (hypothalamic islands composed primarily of the isolated ARC and the ME) choline acetyltransferase (ChAc) activity, a good marker for cholinergic neurons, was not significantly reduced in the ME and was only somewhat reduced in the ARC (2). Treatment of neonatal rats with high doses of monosodium 1-glutamate (MSG) results in a lesion largely restricted to the neurons of the ARC.

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Ultrastructure of Liver in Lactosyl Ceramidosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065602 ◽

1971 ◽

Vol 29 ◽

pp. 312-313

Author(s):

Z. Hruban ◽

J. R. Esterly ◽

G. Dawson ◽

A. O. Stein

Keyword(s):

Connective Tissue ◽

Liver Biopsy ◽

Osmium Tetroxide ◽

Close Contact ◽

Multivesicular Bodies ◽

Bile Canaliculi ◽

Dense Bodies ◽

Marginal Plates ◽

Membranous Material ◽

Perichromatin Granules

Samples of a surgical liver biopsy from a patient with lactosyl ceramidosis were fixed in paraformaldehyde and postfixed in osmium tetroxide. Hepatocytes (Figs. 1, 2) contained 0.4 to 2.1 μ inclusions (LCI) limited by a single membrane containing lucid matrix and short segments of curved, lamellated and circular membranous material (Fig. 3). Numerous LCI in large connective tissue cells were up to 11 μ in diameter (Fig. 2). Heterogeneous dense bodies (“lysosomes”) were few and irregularly distributed. Rough cisternae were dilated and contained smooth vesicles and surface invaginations. Close contact with mitochondria was rare. Stacks were small and rare. Vesicular rough reticulum and glycogen rosettes were abundant. Smooth vesicular reticulum was moderately abundant. Mitochondria were round with few cristae and rare matrical granules. Golgi complex was seen rarely (Fig. 1). Microbodies with marginal plates were usual. Multivesicular bodies were very rare. Neutral lipid was rare. Nucleoli were small and perichromatin granules were large. Small bile canaliculi had few microvilli (Fig. 1).

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