scholarly journals Phosphatase localization in the endomembrane system of the dinoflagellate Crypthecodinium cohnii.

1986 ◽  
Vol 34 (8) ◽  
pp. 1021-1027 ◽  
Author(s):  
S B Barlow ◽  
R E Triemer

The distribution of four enzymes within the endomembrane system of the protist Crypthecodinium cohnii has been determined using cytochemical localizations with lead as a capture agent. Nucleoside diphosphatase (NDPase) activity, using inosine diphosphate (IDP) and thiamine pyrophosphate (TPP) as substrates, was observed in the Golgi apparatus, with a gradient of increasing reaction product noted in some cells from the cis to trans cisternae. Tubules and vesicles associated with the trans cisternae also contained reaction product. The endoplasmic reticulum exhibited a high activity of glucose-6-phosphatase [with glucose-6-phosphate (G-6-P) as substrate]. Traces of reaction product were also observed in the cis-most and trans-most cisternae of the dictyosomes. Activity of acid phosphatase (AcPase) was observed in Golgi cisternae as well as in associated cytoplasmic vesicles. Heaviest deposition was localized in medial and trans dictyosome cisternae. The cytoplasmic system of flattened vesicles subtending the surface membranes in these cells did not exhibit reactivity with any of the substrates used. The distribution of these enzymes in this algal cell appears similar to that observed in animal cells and suggests that these enzymes may represent markers for algal cell endomembrane compartments.

1962 ◽  
Vol 15 (2) ◽  
pp. 289-312 ◽  
Author(s):  
Edward Essner ◽  
Alex B. Novikoff

The Reuber hepatoma H-35 and Morris hepatoma 5123 have been studied by electron microscopy and by cytochemical staining methods for a number of phosphatases. These studies emphasize the resemblances of the two tumors to rat liver, but they also indicate distinctive features in each of the three tissues. Secretory product accumulates within the cisternae of the Golgi apparatus that dilate to form the Golgi vacuoles. The vacuoles apparently separate, and secretory material undergoes further condensation within them. These "secretory vacuoles" possess acid phosphatase activity and may thus be considered lysosomes. The membranes of the Golgi apparatus are without acid phosphatase activity but show high levels of thiaminepyrophosphatase activity. The endoplasmic reticulum also hydrolyzes thiaminepyrophosphate but at a lower rate; it hydrolyzes the diphosphates of uridine, guanosine, and inosine rapidly. These observations and the electron microscopic images are consistent with the view that the cytomembranes are in a dynamic state of flux, movement, and transformation in the living cell, and that smooth surfaced derivatives of the endoplasmic reticulum become refashioned into the Golgi membranes as the Golgi membranes are being refashioned into those that delimit secretory vacuoles. The variations encountered in the two hepatomas are described. The electron microscope literature dealing with the relations of the Golgi apparatus to secretory granules, on the one hand, and the endoplasmic reticulum, on the other, is reviewed briefly.


1980 ◽  
Vol 28 (2) ◽  
pp. 115-123 ◽  
Author(s):  
R A Coleman ◽  
B H Schofield ◽  
D F McDonald

Substrates commonly used for localizing bone Golgi apparatus (GA) acid phosphatase (AcPase), e.g., beta-glycerophosphate, p-nitrophenylphosphate, cytidine-5'-monophosphate, and di(dicyclohexylammonium)-2-napthylthiolphosphate, give strong staining not only of GA but also of lysosomes. Thiamine pyrophosphate and inosine-5'-monophosphate--substrates that give good GA staining in some soft tissues--give only lysosomal staining in bone. No previously used substrate or substrate-effector combination has selectively localized the GA acid phosphatase in bone. This article describes results using a new AcPase medium having pyridoxal-5'-phosphate (PLP) as substrate. In bone this medium produced strong staining of the osteoblast GA, but relatively little staining of lysosomes, including lysosomes in osteoclasts. The weak lysosomal staining was almost totally eliminated, without affecting the GA reaction, by pretreating the tissue in 0.3% NH3 solution. Conversely, elevated ionic strength of the substrate medium eliminated the GA reaction, while having little effect on lysosomal staining. The GA enzyme was very sensitive to 1 mM tartrate whereas the lysosomal enzyme was not. These differences suggest the presence of distinct isoenzymes in the two locations. The distribution of osteoblasts with stained GA coincided with the distribution of strongest alkaline phosphatase activity and rapid bone mineralization, supporting previous suggestions that osteoblast GA AcPase is involved in the processing of one or more newly synthesized bone matrix components.


1983 ◽  
Vol 31 (9) ◽  
pp. 1077-1088 ◽  
Author(s):  
R D Broadwell ◽  
A M Cataldo

The endoplasmic reticulum (ER) and its contribution to the endomembrane system (i.e., membranes of cell organelles) in the neuron have been investigated in brains of mice by applying electron microscopic enzyme cytochemistry for demonstration of glucose-6-phosphatase (G6Pase) activity. The phosphohydrolytic activity of G6Pase is a well-known cytochemical marker for the ER in numerous cell types. Of the different substrates employed, glucose-6-phosphate and mannose-6-phosphate were the only two with which G6Pase reaction product was seen in the neuronal ER and organelles related morphologically to the ER. G6Pase activity in cell bodies and dendrites was localized consistently within the lumen of the nuclear envelope, rough and smooth ER, lamellar bodies, hypolemmal and subsurface cisternae, and frequently in the cis saccules of the Golgi apparatus. The G6Pase reactive ER appeared as a network of saccules and tubules pervading the cell body and its dendrites. Possible membrane continuities were identified between the ER and the other reactive structures, including the cis half of the Golgi apparatus. Neither G6Pase activity nor reactive ER was associated with the trans Golgi saccules or GERL. G6Pase activity thus serves as a reliable marker for the perikaryal and dendritic ER and related structures. These observations support the theory that the ER is an integral component of the neuronal endomembrane system associated with the transfer of membrane or membrane molecules among intracellular compartments, the packaging and transport of exportable protein, and energy metabolism. G6Pase activity in the ER of axons and terminals is considered in detail in part two of this study.


1971 ◽  
Vol 49 (3) ◽  
pp. 899-905 ◽  
Author(s):  
R. D. Cheetham ◽  
D. James Morré ◽  
Carol Pannek ◽  
Daniel S. Friend

The thiamine pyrophosphatase (the enzyme [s] catalyzing the release of inorganic phosphate with thiamine pyrophosphate as the substrate) activities of Golgi apparatus-, plasma membrane-, endoplasmic reticulum-, and mitochondria-rich fractions from rat liver were compared at pH 8. Activity was concentrated in the Golgi apparatus fractions, which, on a protein basis, had a specific activity six to eight times that of the total homogenates or purified endoplasmic reticulum fractions. However, only 1–3% of the total activity was recovered in the Golgi apparatus fractions under conditions where 30–50% of the UDPgalactose:N-acetylglucosamine-galactosyl transferase activity was recovered. Considering both recovery of galactosyl transferase and fraction purity, we estimate that approximately 10% of the total thiamine pyrophosphatase activity of the liver was localized within the Golgi apparatus, with a specific activity of about ten times that of the total homogenate. Cytochemically, reaction product was found in the cisternae of the endoplasmic reticulum as well as in the Golgi apparatus. This is in contrast to results obtained in most other tissues, where reaction product was restricted to the Golgi apparatus. Thus, enzymes of rat liver catalyzing the hydrolysis of thiamine pyrophosphate, although concentrated in the Golgi apparatus, are widely distributed among other cell components in this tissue.


1965 ◽  
Vol 26 (2) ◽  
pp. 523-537 ◽  
Author(s):  
G. Benjamin Bouck

The structural interrelationships among several membrane systems in the cells of brown algae have been examined by electron microscopy. In the brown algae the chloroplasts are surrounded by two envelopes, the outer of which in some cases is continuous with the nuclear envelope. The pyrenoid, when present, protrudes from the chloroplast, is also surrounded by the two chloroplast envelopes, and, in addition, is capped by a third dilated envelope or "pyrenoid sac." The regular apposition of the membranes around the pyrenoid contrasts with their looser appearance over the remainder of the chloroplast. The Golgi apparatus is closely associated with the nuclear envelope in all brown algae examined, but in the Fucales this association may extend to portions of the cytoplasmic endoplasmic reticulum as well. Evidence is presented for the derivation of vesicles, characteristic of those found in the formative region of the Golgi apparatus, from portions of the underlying nuclear envelope. The possibility that a structural channeling system for carbohydrate reserves and secretory precursors may be present in brown algae is considered. Other features of the brown algal cell, such as crystal-containing bodies, the variety of darkly staining vacuoles, centrioles, and mitochondria, are examined briefly, and compared with similar structures in other plant cells.


1968 ◽  
Vol 16 (5) ◽  
pp. 320-336 ◽  
Author(s):  
ERIC HOLTZMAN ◽  
REGINA DOMINITZ

The adrenalin-producing cells of the rat adrenal medulla have been studied by light and electron microscopy. Frozen sections of glutaraldehyde-perfused material were incubated for demonstration of "marker" enzymes for lysosomes (acid phosphatase, aryl sulfatase) and Golgi apparatus (thiamine pyrophosphatase). In addition, the uptake and fate of intravenously administered horseradish peroxidase was followed. Acid phosphatase activity is demonstrable in secretory granules, Golgi saccules, vesicles in the Golgi area and in the agranular tubules and cisternae (GERL) from which secretory granules appear to form at the inner surface of the Golgi apparatus. Endoplasmic reticulum with ribosomes on only one surface is closely apposed to both inner and outer aspects of the Golgi apparatus. Peroxidase is taken up in vesicles, tubules and "cup-like" bodies. The latter apparently transform into multivesicular bodies. A possible source of the acid phosphatase found in multivesicular bodies is the small vesicles from the Golgi apparatus or GERL.


Author(s):  
Béatrice Satiat-Jeunemaitre ◽  
Jancy Henderson ◽  
David Evans ◽  
Kim Crooks ◽  
Mark Fricker ◽  
...  

In plant cells, as in animal cells, many macromolecules and membranes are transported by vesicle vectors through both the exocytotic and endocytotic pathways. In order to elucidate the mechanisms and molecular events of such trafficking we are using a set of drugs known to perturb membrane flow in plant cells in combination with immunocytochemical studies using a bank of monoclonal antibodies to various components of the endomembrane system and cell surface. In animal cells, one such drug, Brefeldin A, a fungal fatty acid derivative which causes disruption of the Golgi apparatus, has recently been used as a tool to dissect the mechanisms of vesicle flow from the endoplasmic reticulum to the Golgi apparatus and down the cisternae of the Golgi stack (1). It has been demonstrated that BFA also has a dramatic effect on the Golgi apparatus in higher plant cells (2,3,4).In this paper we report on recent work on the disruption of the plant Golgi apparatus with BFA and the redistribution of endomembrane marker epitopes after drug treatment of roots and suspension culture cells.


1971 ◽  
Vol 50 (3) ◽  
pp. 859-886 ◽  
Author(s):  
Phyllis M. Novikoff ◽  
Alex B. Novikoff ◽  
Nelson Quintana ◽  
Jean-Jacques Hauw

New insights into the ultrastructure and phosphatase localizations of Golgi apparatus and GERL, and into the probable origin of lysosomes in the neurons of fetal dorsal root ganglia and the small neurons of adult ganglia have come from studying thick (0.5–1.0 µ) as well as thin (up to 500 A) sections by conventional electron microscopy. Tilting the thick specimens, by a goniometer stage, has helped to increase our understanding of the three-dimensional aspects of the Golgi apparatus and GERL. One Golgi element, situated at the inner aspect of the Golgi stack, displays thiamine pyrophosphatase and nucleoside diphosphatase activities. This element exhibits regular geometric arrays (hexagons) of interconnected tubules without evidence of a flattened portion (saccule or cisterna). In contrast, GERL shows acid phosphatase activity and possesses small cisternal portions and anastomosing tubules. Lysosomes appear to bud from GERL. Osmium deposits, following prolonged osmication, are found in the outer Golgi element. Serial 0.5-µ and thin sections of thiamine pyrophosphatase-incubated material demonstrate that, in the neurons studied, the Golgi apparatus is a continuous network coursing through the cytoplasm. Serial thick sections of acid phosphatase-incubated tissue suggest that GERL is also a continuous structure throughout the cytoplasm. Tubules of smooth endoplasmic reticulum, possibly part of GERL, extend into the polygonal compartments of the inner Golgi element. The possible physiological significance of a polygonal arrangement of a phosphatase-rich Golgi element in proximity to smooth ER is considered. A tentative diagram of the Golgi stack and associated endoplasmic reticulum in these neurons has been drawn.


1985 ◽  
Vol 33 (4) ◽  
pp. 339-344 ◽  
Author(s):  
Y Henry ◽  
M W Steer

The intracellular localization of acid phosphatases in stimulated digestive glands of Dionaea flytraps has been studied to provide evidence for the route taken by this enzyme during secretion. Previous studies have either included or excluded a role for the dictyosomes in this pathway. Both p-nitrophenyl phosphate and beta-glycerophosphate were used as substrates, and both gave similar localization patterns. Unstimulated glands contained little phosphatase activity in the endomembrane system, whereas 24 and 48 hr after stimulation, heavy deposits of lead were located in the endoplasmic reticulum cisternae, including the nuclear envelope, the dictyosome cisternae, and secretory vesicles. Since dictyosome activation, as judged by the presence of secretory vesicles in the cytoplasm, also coincides with gland stimulation, we conclude that secretion of the hydrolase enzymes occurs via this route and not, as suggested elsewhere, via direct endoplasmic reticulum to plasma membrane connections.


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