The neuronal endomembrane system. II. The multiple forms of the Golgi apparatus cis element

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.

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

Journal of Histochemistry & Cytochemistry ◽

10.1177/34.8.3016072 ◽

1986 ◽

Vol 34 (8) ◽

pp. 1021-1027 ◽

Cited By ~ 3

Author(s):

S B Barlow ◽

R E Triemer

Keyword(s):

Endoplasmic Reticulum ◽

Acid Phosphatase ◽

Golgi Apparatus ◽

High Activity ◽

Algal Cell ◽

Thiamine Pyrophosphate ◽

Endomembrane System ◽

Animal Cells ◽

Crypthecodinium Cohnii ◽

Cytoplasmic Vesicles

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.

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Brefeldin A affects the endomembrane system and vesicle trafficking in higher plants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146801 ◽

1993 ◽

Vol 51 ◽

pp. 192-193

Author(s):

Béatrice Satiat-Jeunemaitre ◽

Jancy Henderson ◽

David Evans ◽

Kim Crooks ◽

Mark Fricker ◽

...

Keyword(s):

Golgi Apparatus ◽

Higher Plants ◽

Fatty Acid Derivative ◽

Plant Cells ◽

Brefeldin A ◽

Endomembrane System ◽

Animal Cells ◽

Higher Plant ◽

Membrane Flow ◽

Golgi Stack

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.

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Localization of methyltransferase activities throughout the endomembrane system of flax (Linum usitatissimum L) hypocotyls

Biochemical Journal ◽

10.1042/bj2860863 ◽

1992 ◽

Vol 286 (3) ◽

pp. 863-868 ◽

Cited By ~ 26

Author(s):

M P Vannier ◽

B Thoiron ◽

C Morvan ◽

M Demarty

Keyword(s):

Golgi Apparatus ◽

Linum Usitatissimum ◽

Hydroxyl Groups ◽

Endomembrane System ◽

Cell Wall Polysaccharides ◽

Methyl Esterification ◽

Linum Usitatissimum L ◽

Adenosyl Methionine ◽

Culture Duration ◽

Isopycnic Centrifugation

A microsomal fraction from flax hypocotyls (Linum usitatissimum L) showed a methylation ability from S-adenosyl-methionine on to the cell wall polysaccharides. Two kinds of methylation were found: (i) a methyl esterification of uronic acids in the oxalate extracts and (ii) an O-methylation of the hydroxyl groups in the NaOH extracts. The methyltransferase study showed a rapid decrease of the methyl esterification abilities, whereas the O-methylation on to the hydroxyl groups was maintained throughout the culture duration. The localization of such activities in the flax endomembrane system was performed using isopycnic centrifugation. Enzymic marker tests allowed us to identify the different membrane types. Methyltransferase activities in the different enriched fractions appeared to be associated with the Golgi apparatus for the O-methylation, and with the plasma membrane, Golgi apparatus and endoplasmic reticulum compartments for the carboxymethyl esterification.

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A G protein-coupled receptor-like module regulates Cellulose Synthase secretion from the endomembrane system in Arabidopsis

10.1101/2020.10.20.345868 ◽

2020 ◽

Author(s):

Heather E. McFarlane ◽

Daniela Mutwil-Anderwald ◽

Jana Verbančič ◽

Kelsey L. Picard ◽

Timothy E. Gookin ◽

...

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Golgi Apparatus ◽

G Protein ◽

Protein Complex ◽

Cellulose Synthase ◽

Cell Wall Integrity ◽

Cellulose Synthesis ◽

Endomembrane System ◽

G Protein Coupled

AbstractCellulose synthesis is essential for plant morphology, water transport and defense, and provides raw material for biomaterials and fuels. Cellulose is produced at the plasma membrane by Cellulose Synthase (CESA) protein complexes (CSCs). CSCs are assembled in the endomembrane system and then trafficked from the Golgi apparatus and trans-Golgi Network (TGN) to the plasma membrane. Since CESA enzymes are only active in the plasma membrane, control of CSC secretion is a critical step in the regulation of cellulose synthesis. However, the regulatory framework for CSC secretion is not clarified. In this study, we identify members of a family of seven transmembrane domain-containing proteins (7TMs) as important for cellulose production during cell wall integrity stress. 7TM proteins are often associated with guanine nucleotide-binding protein (G) protein signalling and mutants in several of the canonical G protein complex components phenocopied the 7tm mutant plants. Unexpectedly, the 7TM proteins localized to the Golgi apparatus/TGN where they interacted with the G protein complex. Here, the 7TMs and G proteins regulated CESA trafficking, but did not affect general protein secretion. Furthermore, during cell wall stress, 7TMs’ localization was biased towards small CESA-containing vesicles, specifically associated with CSC trafficking. Our results thus outline how a G protein-coupled module regulates CESA trafficking and reveal that defects in this process lead to exacerbated responses upon exposure to cell wall integrity stress.

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The Golgi apparatus regulates cGMP-dependent protein kinase I compartmentation and proteolysis

AJP Cell Physiology ◽

10.1152/ajpcell.00199.2014 ◽

2015 ◽

Vol 308 (11) ◽

pp. C944-C958 ◽

Cited By ~ 4

Author(s):

Shin Kato ◽

Jingsi Chen ◽

Katherine H. Cornog ◽

Huili Zhang ◽

Jesse D. Roberts

Keyword(s):

Protein Kinase ◽

Golgi Apparatus ◽

Protein Transport ◽

Endomembrane System ◽

Dependent Protein Kinase ◽

Trans Golgi Network ◽

Cgmp Dependent Protein Kinase ◽

Cgmp Signaling ◽

Dependent Protein ◽

Golgi Network

cGMP-dependent protein kinase I (PKGI) is an important effector of cGMP signaling that regulates vascular smooth muscle cell (SMC) phenotype and proliferation. PKGI has been detected in the perinuclear region of cells, and recent data indicate that proprotein convertases (PCs) typically resident in the Golgi apparatus (GA) can stimulate PKGI proteolysis and generate a kinase fragment that localizes to the nucleus and regulates gene expression. However, the role of the endomembrane system in PKGI compartmentation and processing is unknown. Here, we demonstrate that PKGI colocalizes with endoplasmic reticulum (ER), ER-Golgi intermediate compartment, GA cisterna, and trans-Golgi network proteins in pulmonary artery SMC and cell lines. Moreover, PKGI localizes with furin, a trans-Golgi network-resident PC known to cleave PKGI. ER protein transport influences PKGI localization because overexpression of a constitutively inactive Sar1 transgene caused PKGI retention in the ER. Additionally, PKGI appears to reside within the GA because PKGI immunoreactivity was determined to be resistant to cytosolic proteinase K treatment in live cells. The GA appears to play a role in PKGI proteolysis because overexpression of inositol 1,4,5-trisphosphate receptor-associated cGMP kinase substrate, not only tethered heterologous PKGI-β to the ER and decreased its localization to the GA, but also diminished PKGI proteolysis and nuclear translocation. Also, inhibiting intra-GA protein transport with monensin was observed to decrease PKGI cleavage. These studies detail a role for the endomembrane system in regulating PKGI compartmentation and proteolysis. Moreover, they support the investigation of mechanisms regulating PKGI-dependent nuclear cGMP signaling in the pulmonary vasculature with Golgi dysfunction.

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Identifying suboptimalities with factorial model comparison

Behavioral and Brain Sciences ◽

10.1017/s0140525x18001541 ◽

2018 ◽

Vol 41 ◽

Cited By ~ 2

Author(s):

Wei Ji Ma

Keyword(s):

Experimental Design ◽

Model Comparison ◽

Process Models ◽

Multiple Forms ◽

Factorial Experimental Design ◽

Factorial Model ◽

Multiple Components ◽

The Many

AbstractGiven the many types of suboptimality in perception, I ask how one should test for multiple forms of suboptimality at the same time – or, more generally, how one should compare process models that can differ in any or all of the multiple components. In analogy to factorial experimental design, I advocate for factorial model comparison.

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Relationship between golgi apparatus and axonal reticulum in sympathetic ganglion cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083862 ◽

1978 ◽

Vol 36 (2) ◽

pp. 598-599

Author(s):

J. Quatacker ◽

W. De Potter

Keyword(s):

Golgi Apparatus ◽

Sympathetic Ganglion ◽

Phosphotungstic Acid ◽

Ganglion Cells ◽

Low Ph ◽

Dense Core ◽

Dense Core Vesicles ◽

Large Dense Core Vesicles ◽

Cervical Ganglia ◽

Axoplasmic Reticulum

Mucopolysaccharides have been demonstrated biochemically in catecholamine-containing subcellular particles in different rat, cat and ox tissues. As catecholamine-containing granules seem to arise from the Golgi apparatus and some also from the axoplasmic reticulum we examined wether carbohydrate macromolecules could be detected in the small and large dense core vesicles and in structures related to them. To this purpose superior cervical ganglia and irises from rabbit and cat and coeliac ganglia and their axons from dog were subjected to the chromaffin reaction to show the distribution of catecholamine-containing granules. Some material was also embedded in glycolmethacrylate (GMA) and stained with phosphotungstic acid (PTA) at low pH for the detection of carbohydrate macromolecules.The chromaffin reaction in the perikarya reveals mainly large dense core vesicles, but in the axon hillock, the axons and the terminals, the small dense core vesicles are more prominent. In the axons the small granules are sometimes seen inside a reticular network (fig. 1).

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Golgi Apparatus and Melanogenesis: Ultrastructural Study of a Human Cellular Blue Nevus (Melanocytoma)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072344 ◽

1973 ◽

Vol 31 ◽

pp. 380-381

Author(s):

S.R. Allegra

Keyword(s):

Endoplasmic Reticulum ◽

Golgi Apparatus ◽

Ultrastructural Study ◽

The Other ◽

Blue Nevus ◽

Normal Complement ◽

Golgi Vesicles ◽

Golgi System ◽

The Subject ◽

Cellular Blue Nevus

The respective roles of the ribo somes, endoplasmic reticulum, Golgi apparatus and perhaps nucleus in the synthesis and maturation of melanosomes is still the subject of some controversy. While the early melanosomes (premelanosomes) have been frequently demonstrated to originate as Golgi vesicles, it is undeniable that these structures can be formed in cells in which Golgi system is not found. This report was prompted by the findings in an essentially amelanotic human cellular blue nevus (melanocytoma) of two distinct lines of melanocytes one of which was devoid of any trace of Golgi apparatus while the other had normal complement of this organelle.

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