ASTROCYTES TREATED WITH BREFELDIN A, OR OKADAIC ACID SHOW FRAGMENTATION OF THE GOLGI APPARATUS AND CYTOPLASMIC ACCUMULATIONS OF INTERMEDIATE FILAMENTS AND VESICLES

1998 ◽  
Vol 57 (5) ◽  
pp. 516
Author(s):  
Nicholas K. Gonatas ◽  
Anna Stieber ◽  
Quiang Wang ◽  
Ehud Lavi
Keyword(s):  
Golgi Apparatus ◽  
Intermediate Filaments ◽  
Okadaic Acid ◽  
Brefeldin A

scholarly journals Structural Integrity of the Golgi Stack Is Essential for Normal Secretory Functions of Rat Parotid Acinar Cells: Effects of Brefeldin A and Okadaic Acid

2002 ◽  
Vol 50 (12) ◽  
pp. 1611-1623 ◽  
Author(s):  
Hideaki Tamaki ◽  
Shohei Yamashina
Keyword(s):  
Golgi Apparatus ◽  
Okadaic Acid ◽  
Cathepsin D ◽  
Structural Integrity ◽  
Brefeldin A ◽  
Acinar Cells ◽  
Ultrastructural Organization ◽  
Golgi Stack ◽  
Parotid Acinar Cells ◽  
Rat Parotid

We examined the effects of specific inhibitors, brefeldin A (BFA) and okadaic acid (OA), on the ultrastructural organization of the Golgi apparatus and distributions of amylase, Golgi-associated proteins, and cathepsin D in the rat parotid acinar cells. BFA induced a rapid regression of the Golgi stack into rudimentary Golgi clusters composed of tubulovesicules, in parallel with a redistribution of the Golgi-resident proteins and a coat protein (β-COP) into the region of the rough endoplasmic reticulum (rER) or cytosol. The rapid disruption of the Golgi stack could also be induced by the effect of OA. However, redistribution of the Golgi proteins in rER or cytosol could not be observed and β-COP was not dispersed but was retained on the rudimentary Golgi apparatus. These findings suggested that the mechanism of OA in inducing degeneration of the Golgi stack was markedly different from that of BFA. In addition, missorting of amylase, a Golgi protein, and cathepsin D into incorrect transport pathways is apparent in the course of the disruption of the Golgi stack by OA. These Golgi-disrupting effects are reversible and the reconstruction of the stacked structure of the Golgi apparatus started immediately after the removal of inhibitors. In the recovery processes, missorting was also observed until the integrated structure of the Golgi apparatus was completely reconstructed. This suggested that the integrated structure of the Golgi apparatus was quite necessary for the occurrence of normal secretory events, including proper sorting of molecules.

scholarly journals Golgi-Disturbing Agents Lead to the Elimination of Intracellular Toxoplasma gondii

2009 ◽  
Vol 2 (1) ◽  
pp. 10-19 ◽  
Author(s):  
C. S. Carvalho ◽  
G. R. Figueiredo ◽  
E. J. T. de Melo
Keyword(s):  
Retinoic Acid ◽  
Toxoplasma Gondii ◽  
Golgi Apparatus ◽  
Okadaic Acid ◽  
Golgi Complex ◽  
Secretory Pathway ◽  
Brefeldin A ◽  
Host Cells ◽  
Parasite Development ◽  
Intracellular Medium

The Golgi apparatus is responsible for the genesis of secretory organelles of Toxoplasma gondii and lipid traffic to the vacuole. This study used anti-Golgi agents to demonstrate the importance of Golgi in Toxoplasma development. Monensin, Brefeldin A, Retinoic Acid and Okadaic Acid reduced the infection, leading to parasite elimination. Mon, BFA and RA affected secretory organelles and the Golgi Complex of the parasites, with faster parasite elimination in the presence of Monensin; in addition, the vesicular transit of host cell C6-NBD-ceramide metabolites was interrupted, but the GC of host cells was preserved. Our results suggest that several targets in the secretory pathway are affected in the intracellular Toxoplasma rather than in the host cells, resulting in interruption of parasite development and its elimination from the intracellular medium.

Important role for the V-type H+-ATPase and the Golgi apparatus in the recycling of PTH/PTHrP receptor

2004 ◽  
Vol 286 (5) ◽  
pp. E704-E710 ◽  
Author(s):  
Hesham A. W. Tawfeek ◽  
Abdul B. Abou-Samra
Keyword(s):  
Golgi Apparatus ◽  
Fluorescent Protein ◽  
Brefeldin A ◽  
Receptor Recycling ◽  
Bafilomycin A1 ◽  
Coated Pits ◽  
Concanamycin A ◽  
Hydrogen Atpase ◽  
Green Fluorescent ◽  
Pthrp Receptor

Our previous studies demonstrated that a green fluorescent protein-tagged parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor stably expressed in LLCPK-1 cells undergoes agonist-dependent internalization into clathrin-coated pits. The subcellular localization of the internalized PTH/PTHrP receptor is not known. In the present study, we explored the intracellular pathways of the internalized PTH/PTHrP receptor. Using immunofluorescence and confocal microscopy, we show that the internalized receptors localize at a juxtanuclear compartment identified as the Golgi apparatus. The receptors do not colocalize with lysosomes. Furthermore, whereas the internalized receptors exhibit rapid recycling, treatment with proton pump inhibitors (bafilomycin-A1 and concanamycin A) or brefeldin A, Golgi disrupting agents, reduces PTH/PTHrP receptor recycling. Together, these data indicate an important role for the vacuolar-type hydrogen-ATPase and the Golgi apparatus in postendocytic PTH/PTHrP receptor recovery.

scholarly journals Brefeldin A inhibits transport of the glycophorin-binding protein from Plasmodium falciparum into the host erythrocyte

1994 ◽  
Vol 300 (3) ◽  
pp. 821-826 ◽  
Author(s):  
J Benting ◽  
D Mattei ◽  
K Lingelbach
Keyword(s):  
Plasmodium Falciparum ◽  
Golgi Apparatus ◽  
Host Cell ◽  
Protein Secretion ◽  
Secretory Pathway ◽  
Binding Protein ◽  
Brefeldin A ◽  
Cell Cytoplasm ◽  
Parasite Cell ◽  
Host Cell Cytoplasm

Plasmodium falciparum, a protozoan parasite of the human erythrocyte, causes the most severe form of malaria. During its intraerythrocytic development, the parasite synthesizes proteins which are exported into the host cell. The compartments involved in the secretory pathway of P. falciparum are still poorly characterized. A Golgi apparatus has not been identified, owing to the lack of specific protein markers and Golgi-specific post-translational modifications in the parasite. The fungal metabolite brefeldin A (BFA) is known to inhibit protein secretion in higher eukaryotes by disrupting the integrity of the Golgi apparatus. We have used the parasite-encoded glycophorin-binding protein (GBP), a soluble protein found in the host cell cytoplasm, as a marker to investigate the effects of BFA on protein secretion in the intracellular parasite. In the presence of BFA, GBP was not transported into the erythrocyte, but remained inside the parasite cell. The effect caused by BFA was reversible, and the protein could be chased into the host cell cytoplasm within 30 min. Transport of GBP from the BFA-sensitive site into the host cell did not require protein synthesis. Similar observations were made when infected erythrocytes were incubated at 15 degrees C. Incubation at 20 degrees C resulted in a reduction rather than a complete block of protein export. The relevance of our findings to the identification of compartments involved in protein secretion from the parasite cell is discussed.

scholarly journals Cisternal Rab Proteins Regulate Golgi Apparatus Redistribution in Response to Hypotonic Stress

2005 ◽  
Vol 16 (5) ◽  
pp. 2586-2596 ◽  
Author(s):  
Shu Jiang ◽  
Brian Storrie
Keyword(s):  
Golgi Apparatus ◽  
Physiological Role ◽  
Brefeldin A ◽  
Inhibitory Effect ◽  
Rab Proteins ◽  
Hypotonic Stress ◽  
Rab Protein ◽  
Dependent Process ◽  
Response To Stress ◽  
Independent Process

We show that a physiological role of the extensively studied cisternal Golgi rab protein, rab6, is modulation of Golgi apparatus response to stress. Taking exposure of cells to hypotonic media as the best-known example of mammalian Golgi stress response, we found that hypotonic-induced tubule extension from the Golgi apparatus was sensitive to GDP-rab6a expression. Similarly, we found that Golgi tubulation induced by brefeldin A, a known microtubule-dependent process, was inhibited by GDP-restricted rab6a, rab6a′, and rab33b, the most commonly studied cisternal rab proteins. These GDP-rab levels were sufficient to inhibit rab-induced redistribution of Golgi glycosyltransferases into the endoplasmic reticulum (ER), also a microtubule-dependent process, and to depress Golgi membrane association of the GTP-conformer of rab6. Nocodazole-induced Golgi scattering, a microtubule-independent process, also was inhibited by GDP-rab6a expression. In comparison, we found similar GDP-rab expression levels had little inhibitory effect on another microtubule-independent process, constitutive recycling of Golgi resident proteins to the ER. We conclude that Golgi cisternal rabs, and in particular rab6a, are regulators of the Golgi response to stress and presumably the molecular targets of stress-activated signaling pathway(s). Moreover, we conclude that rab6a can regulate select microtubule-independent processes as well as microtubule-dependent processes.

scholarly journals Capacity of the Golgi Apparatus for Biogenesis from the Endoplasmic Reticulum

2003 ◽  
Vol 14 (12) ◽  
pp. 5011-5018 ◽  
Author(s):  
Sapna Puri ◽  
Adam D. Linstedt
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Self Assembly ◽  
De Novo ◽  
Brefeldin A ◽  
The Other ◽  
Matrix Proteins ◽  
Er Export ◽  
Golgi Matrix

It is unclear whether the mammalian Golgi apparatus can form de novo from the ER or whether it requires a preassembled Golgi matrix. As a test, we assayed Golgi reassembly after forced redistribution of Golgi matrix proteins into the ER. Two conditions were used. In one, ER redistribution was achieved using a combination of brefeldin A (BFA) to cause Golgi collapse and H89 to block ER export. Unlike brefeldin A alone, which leaves matrix proteins in relatively large remnant structures outside the ER, the addition of H89 to BFA-treated cells caused ER accumulation of all Golgi markers tested. In the other, clofibrate treatment induced ER redistribution of matrix and nonmatrix proteins. Significantly, Golgi reassembly after either treatment was robust, implying that the Golgi has the capacity to form de novo from the ER. Furthermore, matrix proteins reemerged from the ER with faster ER exit rates. This, together with the sensitivity of BFA remnants to ER export blockade, suggests that presence of matrix proteins in BFA remnants is due to cycling via the ER and preferential ER export rather than their stable assembly in a matrix outside the ER. In summary, the Golgi apparatus appears capable of efficient self-assembly.

scholarly journals Mammalian Cdc42 Is a Brefeldin A-sensitive Component of the Golgi Apparatus

1996 ◽  
Vol 271 (43) ◽  
pp. 26850-26854 ◽  
Author(s):  
Jon W. Erickson ◽  
Chun-jiang Zhang ◽  
Richard A. Kahn ◽  
Tony Evans ◽  
Richard A. Cerione
Keyword(s):  
Golgi Apparatus ◽  
Brefeldin A
Sign in / Sign up

Export Citation Format

Share Document