Effects of brefeldin A on the Golgi apparatus, the nuclear envelope, and the endoplasmic reticulum in a green alga,Scenedesmus acutus

The primary nucleus of the green alga Acetabularia grows about 25,000-fold in volume while it is separated from the endoplasmic reticulum and the whole cytoplasm by a special paranuclear cisterna of a vacuolar labyrinthum system which shows only very few (two to six per square micrometer) and small (ca. 40-120 nm in diamter) fenestrations. The nuclear envelope does not bear polyribosomes, nor do they occur in the entire zone intermediate between the nuclear envelope and the paranuclear cisterna. It is suggested that this special form of nuclear envelope growth takes place by assembly from cytoplasmically synthesized proteins that are translocated across the paranuclear cisterna in a nonmembrane-structured form.

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Functional Protein Prenylation Is Required for the Brefeldin A-dependent Retrograde Transport from the Golgi Apparatus to the Endoplasmic Reticulum

Journal of Biological Chemistry ◽

10.1074/jbc.272.33.20828 ◽

1997 ◽

Vol 272 (33) ◽

pp. 20828-20834 ◽

Cited By ~ 13

Author(s):

N. Erwin Ivessa ◽

Diego Gravotta ◽

Carmen De Lemos-Chiarandini ◽

Gert Kreibich

Keyword(s):

Endoplasmic Reticulum ◽

Golgi Apparatus ◽

Brefeldin A ◽

Retrograde Transport ◽

Protein Prenylation ◽

Functional Protein

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Capacity of the Golgi Apparatus for Biogenesis from the Endoplasmic Reticulum

Molecular Biology of the Cell ◽

10.1091/mbc.e03-06-0437 ◽

2003 ◽

Vol 14 (12) ◽

pp. 5011-5018 ◽

Cited By ~ 62

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.

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Elektronenmikroskopische Beobachtungen an der vegetativen Zelle im auskeimenden Pollenkorn von Oenothera hookeri Torr. et Grey

Zeitschrift für Naturforschung B ◽

10.1515/znb-1963-1219 ◽

1963 ◽

Vol 18 (12) ◽

pp. 1092-1097 ◽

Cited By ~ 8

Author(s):

Lothar Diers

Keyword(s):

Endoplasmic Reticulum ◽

Golgi Apparatus ◽

Nuclear Envelope ◽

Vegetative Cell ◽

Generative Cell ◽

Pollen Grain ◽

Serial Sections ◽

Lipid Inclusions ◽

Intense Activity ◽

Germinating Pollen

According to the intense activity of the vegetative cell in the germinating pollen grain, the cytoplasm shows a highly organized structure. Concerning the structure the vegetative cell differs strongly from the generative cell. In the vegetative cell the big nucleus shows a very lobed shape. Large invaginations of the cytoplasm into the nucleus can be frequently observed. Series of adjacent sections show that deep and flat vesicles which may often broaden to unusual large cisternae, extend through the vegetative plasm and form by interconnections a highly developed endoplasmic reticulum which is continuous with the nuclear envelope. The leucoplasts contain large starch grains and very few lamellae, in many sections only one lamella is visible. Sometimes, a process of a leucoplast deeply reaches into another leucoplast. In some leucoplasts and mitochondria there are concentric stripes which, according to serial sections, are the margins of invaginations of the cytoplasm or of another organell. In the numerous mitochondria the inner folds have the form of cristae, tubules are not so frequently seen. The edges of the flattened sacs of the Golgi - apparatus expand to vacuoles which seem to separate from the flattened cisternae. Typical for the vegetative plasm are numerous small vacuoles. Relatively large, ringshaped or uniform dark bodies are assumed to be lipid inclusions.

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FINE STRUCTURE AND ORGANELLE ASSOCIATIONS IN BROWN ALGAE

The Journal of Cell Biology ◽

10.1083/jcb.26.2.523 ◽

1965 ◽

Vol 26 (2) ◽

pp. 523-537 ◽

Cited By ~ 155

Author(s):

G. Benjamin Bouck

Keyword(s):

Electron Microscopy ◽

Endoplasmic Reticulum ◽

Fine Structure ◽

Golgi Apparatus ◽

Nuclear Envelope ◽

Brown Algae ◽

Algal Cell ◽

Plant Cells ◽

Membrane Systems ◽

Two Envelopes

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.

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Ultrastructure of mononuclear phagocytes developing in liquid bone marrow cultures. A study on peroxidatic activity

Journal of Experimental Medicine ◽

10.1084/jem.149.1.17 ◽

1979 ◽

Vol 149 (1) ◽

pp. 17-26 ◽

Cited By ~ 46

Author(s):

JWM Van Der Meer ◽

RHJ Beelen ◽

DM Fluitsma ◽

R Van Furth

Keyword(s):

Bone Marrow ◽

Endoplasmic Reticulum ◽

Golgi Apparatus ◽

Nuclear Envelope ◽

Rough Endoplasmic Reticulum ◽

Precursor Cells ◽

Mononuclear Phagocytes ◽

Peroxidatic Activity

Monoblasts, promonocytes, and macrophages in in vitro cultures of murine bone marrow were studied ultrastructurally, with special attention to peroxidatic activity. Monoblasts show peroxidatic activity in the rough endoplasmic reticulum and nuclear envelope as well as in the granules. The presence of peroxidatic activity in the Golgi apparatus could not be determined. Promonocytes have peroxidase-positive rough endoplasmic reticulum, Golgi apparatus, nuclear envelope, and granules, as previously reported. During culture, cells are formed with peroxidatic activity similar to that of monocytes or exudate macrophages (positive granules; negative Golgi apparatus, RER, and nuclear envelope); we call these cells early macrophages. In addition, transitional macrophages with both positive granules and positive RER, nuclear envelope, negative Golgi apparatus (as in exudate- resident macrophages in vivo), and mature macrophages with peroxidatic activity only in the RER and nuclear envelope (as in resident macrophages in vivo) were found. A considerable number of cells without detectable peroxidatic activity were also encountered. Our finding that macrophages with the peroxidatic pattern of monocytes (early macrophages), exudate-resident macrophages (transitional macrophages), and resident macrophages (mature macrophages), develop in vitro from proliferating precursor cells deriving from the bone marrow, demonstrates once again that resident macrophages in tissues originate from precursor cells in the bone marrow. Therefore, this conclusion can no longer be challenged on the basis of a cytochemical difference between monocytes and exudate macrophages on the one hand and resident macrophages on the other.

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Transport of Bacterial Lipopolysaccharide to the Golgi Apparatus

Journal of Experimental Medicine ◽

10.1084/jem.190.4.523 ◽

1999 ◽

Vol 190 (4) ◽

pp. 523-534 ◽

Cited By ~ 93

Author(s):

Nathalie Thieblemont ◽

Samuel D. Wright

Keyword(s):

Endoplasmic Reticulum ◽

Golgi Apparatus ◽

Hela Cells ◽

Brefeldin A ◽

Cellular Responses ◽

Epithelial Cell Line ◽

Cholera Toxin B Subunit ◽

B Subunit ◽

Cell Line Hela ◽

Tetramethylrhodamine Isothiocyanate

Addition of lipopolysaccharide (LPS) to cells in the form of LPS–soluble (s)CD14 complexes induces strong cellular responses. During this process, LPS is delivered from sCD14 to the plasma membrane, and the cell-associated LPS is then rapidly transported to an intracellular site. This transport appears to be important for certain cellular responses to LPS, as drugs that block transport also inhibit signaling and cells from LPS-hyporesponsive C3H/HeJ mice fail to exhibit this transport. To identify the intracellular destination of fluorescently labeled LPS after its delivery from sCD14 into cells, we have made simultaneous observations of different organelles using fluorescent vital dyes or probes. Endosomes, lysosomes, the endoplasmic reticulum, and the Golgi apparatus were labeled using Texas red (TR)–dextran, LysoTracker™ Red DND-99, DiOC6(3), and boron dipyrromethane (BODIPY)–ceramide, respectively. After 30 min, LPS did not colocalize with endosomes, lysosomes, or endoplasmic reticulum in polymorphonuclear leukocytes, although some LPS-positive vesicles overlapped with the endosomal marker, fluorescent dextran. On the other hand, LPS did appear to colocalize with two markers of the Golgi apparatus, BODIPY–ceramide and TRITC (tetramethylrhodamine isothiocyanate)–labeled cholera toxin B subunit. We further confirmed the localization of LPS in the Golgi apparatus using an epithelial cell line, HeLa, which responds to LPS–sCD14 complexes in a CD14-dependent fashion: BODIPY–LPS was internalized and colocalized with fluorescently labeled Golgi apparatus probes in live HeLa cells. Morphological disruption of the Golgi apparatus in brefeldin A–treated HeLa cells caused intracellular redistribution of fluorescent LPS. These results are consistent with the Golgi apparatus being the primary delivery site of monomeric LPS.

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The Nrf1 CNC/bZIP protein is a nuclear envelope-bound transcription factor that is activated by t-butyl hydroquinone but not by endoplasmic reticulum stressors

Biochemical Journal ◽

10.1042/bj20081575 ◽

2009 ◽

Vol 418 (2) ◽

pp. 293-310 ◽

Cited By ~ 47

Author(s):

Yiguo Zhang ◽

John M. Lucocq ◽

John D. Hayes

Keyword(s):

Endoplasmic Reticulum ◽

Nuclear Envelope ◽

Brefeldin A ◽

Integral Membrane Protein ◽

Subcellular Fractionation ◽

Multiple Point ◽

Related Factor ◽

Rich Domain ◽

Membrane Microdomain ◽

Type Factor

In rat liver RL-34 cells, endogenous Nrf1 (nuclear factor-erythroid 2 p45 subunit-related factor 1) is localized in the ER (endoplasmic reticulum) where it exists as a glycosylated protein. Electron microscopy has demonstrated that ectopic Nrf1 in COS-1 cells is located in the ER and the NE (nuclear envelope). Subcellular fractionation, together with a membrane proteinase protection assay, revealed that Nrf1 is an integral membrane protein with both luminal and cytoplasmic domains. The N-terminal 65 residues of Nrf1 direct its integration into the ER and NE membranes and tether it to a Triton X-100-resistant membrane microdomain that is associated with lipid rafts. The activity of Nrf1 was increased by the electrophile tBHQ (t-butyl hydroquinone) probably through an N-terminal domain-dependent process. We found that the NST (Asn/Ser/Thr-rich) domain, along with AD1 (acidic domain 1), contributes positively to the transactivation activity of full-length Nrf1. Furthermore, the NST domain contains seven putative -Asn-Xaa-Ser/Thr- glycosylation sites and, when glycosylation was prevented by replacing all of the seven asparagine residues with either glutamine (Nrf11–7×N/Q) or aspartic acid (Nrf11–7×N/D), the former multiple point mutant possessed less activity than the wild-type factor, whereas the latter mutant exhibited substantially greater activity. Lastly, the ER stressors tunicamycin, thapsigargin and Brefeldin A were found to inhibit basal Nrf1 activity by ∼25%, and almost completely prevented induction of Nrf1-mediated transactivation by tBHQ. Collectively, these results suggest that the activity of Nrf1 critically depends on its topology within the ER, and that this is modulated by redox stressors, as well as by its glycosylation status.

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cis-Golgi proteins accumulate near the ER exit sites and act as the scaffold for Golgi regeneration after brefeldin A treatment in tobacco BY-2 cells

Molecular Biology of the Cell ◽

10.1091/mbc.e12-01-0034 ◽

2012 ◽

Vol 23 (16) ◽

pp. 3203-3214 ◽

Cited By ~ 49

Author(s):

Yoko Ito ◽

Tomohiro Uemura ◽

Keiko Shoda ◽

Masaru Fujimoto ◽

Takashi Ueda ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Golgi Apparatus ◽

Fluorescent Proteins ◽

Plant Cells ◽

Brefeldin A ◽

Eukaryotic Cells ◽

Er Exit Sites ◽

Intermediate Compartment ◽

Golgi Protein ◽

And Function

The Golgi apparatus forms stacks of cisternae in many eukaryotic cells. However, little is known about how such a stacked structure is formed and maintained. To address this question, plant cells provide a system suitable for live-imaging approaches because individual Golgi stacks are well separated in the cytoplasm. We established tobacco BY-2 cell lines expressing multiple Golgi markers tagged by different fluorescent proteins and observed their responses to brefeldin A (BFA) treatment and BFA removal. BFA treatment disrupted cis, medial, and trans cisternae but caused distinct relocalization patterns depending on the proteins examined. Medial- and trans-Golgi proteins, as well as one cis-Golgi protein, were absorbed into the endoplasmic reticulum (ER), but two other cis-Golgi proteins formed small punctate structures. After BFA removal, these puncta coalesced first, and then the Golgi stacks regenerated from them in the cis-to-trans order. We suggest that these structures have a property similar to the ER-Golgi intermediate compartment and function as the scaffold of Golgi regeneration.

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