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BMB Reports May 2021The Golgi complex plays a central role in protein secretion by regulating cargo sorting and trafficking. As these processes are of functional importance to cell... (Review)
Review
The Golgi complex plays a central role in protein secretion by regulating cargo sorting and trafficking. As these processes are of functional importance to cell polarity, motility, growth, and division, there is considerable interest in achieving a comprehensive understanding of Golgi complex biology. However, the unique stack structure of this organelle has been a major hurdle to our understanding of how proteins are secreted through the Golgi apparatus. Herein, we summarize available relevant research to gain an understanding of protein secretion via the Golgi complex. This includes the molecular mechanisms of intra-Golgi trafficking and cargo export in the trans-Golgi network. Moreover, we review recent insights on signaling pathways regulated by the Golgi complex and their physiological significance. [BMB Reports 2021; 54(5): 246-252].
Topics: Golgi Apparatus; Humans; Proteins
PubMed: 33612152
DOI: 10.5483/BMBRep.2021.54.5.270 -
ELife Aug 2020The design principles dictating the spatio-temporal organisation of eukaryotic cells, and in particular the mechanisms controlling the self-organisation and dynamics of...
The design principles dictating the spatio-temporal organisation of eukaryotic cells, and in particular the mechanisms controlling the self-organisation and dynamics of membrane-bound organelles such as the Golgi apparatus, remain elusive. Although this organelle was discovered 120 years ago, such basic questions as whether vesicular transport through the Golgi occurs in an anterograde (from entry to exit) or retrograde fashion are still strongly debated. Here, we address these issues by studying a quantitative model of organelle dynamics that includes: de-novo compartment generation, inter-compartment vesicular exchange, and biochemical conversion of membrane components. We show that anterograde or retrograde vesicular transports are asymptotic behaviors of a much richer dynamical system. Indeed, the structure and composition of cellular compartments and the directionality of vesicular exchange are intimately linked. They are emergent properties that can be tuned by varying the relative rates of vesicle budding, fusion and biochemical conversion.
Topics: Biological Transport; Golgi Apparatus; Models, Biological; Transport Vesicles
PubMed: 32755543
DOI: 10.7554/eLife.47318 -
Cold Spring Harbor Symposia on... 1995
Review
Topics: Animals; Capsid; Carrier Proteins; Golgi Apparatus; Golgi Matrix Proteins; Membrane Proteins; Microscopy, Electron; Mitosis; Models, Biological; Prophase; SNARE Proteins; Soluble N-Ethylmaleimide-Sensitive Factor Attachment Proteins; Vesicular Transport Proteins
PubMed: 8824427
DOI: 10.1101/sqb.1995.060.01.058 -
Histochemistry and Cell Biology 1998The secretory apparatus within all eukaryotic cells comprises a dynamic membrane system with bidirectional membrane transport pathways and overlapping compartmental... (Review)
Review
The secretory apparatus within all eukaryotic cells comprises a dynamic membrane system with bidirectional membrane transport pathways and overlapping compartmental boundaries. Membrane traffic and organelle biogenesis/maintenance are fundamentally linked within this system, with perturbations in membrane traffic quickly leading to changes in organelle structure and identity. Dissection of the molecular basis of these properties in yeast and mammalian cells has revealed a crucial role for the cytoplasmic protein complex ARF1/COPI, which undergoes regulated assembly and disassembly with membranes. ARF1/COPI appears to be involved in the formation and maintenance of the Golgi complex, which is the receiving and delivery station for all secretory traffic. ARF1-GTP, through assembly of COPI to membranes and, possibly, through activation of PLD, is likely to promote the formation and maturation of pre-Golgi intermediates into Golgi elements, whereas ARF-GDP causes COPI dissociation and stimulates the formation of retrograde transport structures that recycle Golgi membrane back to the ER. These processes are appear to underlie the coupling of organelle biogenesis and membrane trafficking within cells, allowing the size and shape of secretory organelles to be altered in response to changing cellular needs. Future work needs to address how the activation and localization of ARF1/COPI to membranes as well as other related factors are temporally and spatially regulated, and by what mechanism they transform membrane shape and dynamics to facilitate protein transport and compartmental functioning.
Topics: ADP-Ribosylation Factor 1; ADP-Ribosylation Factors; Animals; Biological Transport; Carrier Proteins; Coatomer Protein; GTP-Binding Proteins; Golgi Apparatus; Humans; Membrane Proteins
PubMed: 9681627
DOI: 10.1007/s004180050247 -
Histochemistry and Cell Biology Feb 2002Wheat germ agglutinin labelled with horseradish peroxidase (WGA) was used for analyses of endosomal compartments and Golgi apparatus in HepG(2) hepatoma cells during...
Wheat germ agglutinin labelled with horseradish peroxidase (WGA) was used for analyses of endosomal compartments and Golgi apparatus in HepG(2) hepatoma cells during early and late periods of endocytosis. WGA was rapidly transferred into the Golgi region. Transport of internalised WGA into the Golgi apparatus could be classified in three stages. A short stage I, characterised by predominance of vesicular endosomes, was followed by stage II showing new formations of extended endocytic trans Golgi networks (TGNs); the endocytic TGNs comprised reticular and globular parts, showed intimate associations with segments of the endoplasmic reticulum and budding of multiple coated vesicles. Parts of the endocytic TGNs associated with trans Golgi cisternae and became integrated into Golgi stacks. During stage III, concomitantly with integration into the stacks, the endocytic TGNs decreased in size and stacked Golgi cisternae became prominent endocytic compartments. Our results show that endocytosis of WGA is connected with extensive membrane dynamics at the trans Golgi side: an endocytic TGN is newly formed, increases in size and is consumed again. The findings suggest that incorporation of TGN elements into Golgi stacks provides a mechanism for uptake of internalised WGA into the Golgi apparatus.
Topics: Endocytosis; Golgi Apparatus; Horseradish Peroxidase; Humans; Microscopy, Electron; Tumor Cells, Cultured; Wheat Germ Agglutinins
PubMed: 11935290
DOI: 10.1007/s00418-001-0371-1 -
Histochemistry and Cell Biology 1998Cell-free systems for the analysis of Golgi apparatus membrane traffic rely either on highly purified cell fractions or analysis by specific trafficking markers or both.... (Review)
Review
Cell-free systems for the analysis of Golgi apparatus membrane traffic rely either on highly purified cell fractions or analysis by specific trafficking markers or both. Our work has employed a cell-free transfer system from rat liver based on purified fractions. Transfer of any constituent present in the donor fraction that can be labeled (protein, phospholipid, neutral lipid, sterol, or glycoconjugate) may be investigated in a manner not requiring a processing assay. Transition vesicles were purified and Golgi apparatus cisternae were subfractionated by means of preparative free-flow electrophoresis. Using these transition vesicles and Golgi apparatus subfractions, transfer between transitional endoplasmic reticulum and cis Golgi apparatus was investigated and the process subdivided into vesicle formation and vesicle fusion steps. In liver, vesicle formation exhibited both ATP-independent and ATP-dependent components whereas vesicle fusion was ATP-independent. The ATP-dependent component of transfer was donor and acceptor specific and appeared to be largely unidirectional, i.e., ATP-dependent retrograde (cis Golgi apparatus to transitional endoplasmic reticulum) traffic was not observed. ATP-dependent transfer in the liver system and coatomer-driven ATP-independent transfer in more refined yeast and cultured cell systems are compared and discussed in regard to the liver system. A model mechanism developed for ATP-dependent budding is proposed where a retinol-stimulated and brefeldin A-inhibited NADH protein disulfide oxidoreductase (NADH oxidase) with protein disulfide-thiol interchange activity and an ATP-requiring protein capable of driving physical membrane displacement are involved. It has been suggested that this mechanism drives both the cell enlargement and the vesicle budding that may be associated with the dynamic flow of membranes along the endoplasmic reticulum-vesicle-Golgi apparatus-plasma membrane pathway.
Topics: Animals; Biological Transport; Cell Membrane; Cell-Free System; Golgi Apparatus; Humans; Liver; Rats
PubMed: 9681630
DOI: 10.1007/s004180050250 -
Histochemistry and Cell Biology Nov 2021The three-dimensional morphology of the Golgi apparatus in osteoclasts was investigated by computer-aided reconstruction. Rat femora were treated for nicotinamide...
The three-dimensional morphology of the Golgi apparatus in osteoclasts was investigated by computer-aided reconstruction. Rat femora were treated for nicotinamide adenine dinucleotide phosphatase (NADPase) cytochemistry, and light microscopy was used to select several osteoclasts in serial semi-thin sections to investigate the Golgi apparatus by backscattered electron-mode scanning electron microscopy. Lace-like structures with strong backscattered electron signals were observed around the nuclei. These structures, observed within the Golgi apparatus, were attributed to the reaction products (i.e., lead precipitates) of NADPase cytochemistry. Features on the images corresponding to the Golgi apparatus, nuclei, and ruffled border were manually traced and three-dimensionally reconstructed using ImageJ/Fiji (an open-source image processing package). In the reconstructed model, the Golgi apparatus formed an almost-continuous structure with a basket-like configuration, which surrounded all the nuclei and also partitioned them. This peculiar three-dimensional morphology of the Golgi apparatus was discovered for the first time in this study. On the basis of the location of the cis- and trans-sides of the Golgi apparatus and the reported results of previous studies, we postulated that the nuclear membrane synthesized specific proteins in the osteoclasts and, accordingly, the Golgi apparatus accumulated around the nuclei as a receptacle.
Topics: Animals; Golgi Apparatus; Histocytochemistry; Imaging, Three-Dimensional; Male; Microscopy, Electron, Scanning; NADP; Osteoclasts; Rats; Rats, Wistar
PubMed: 34436644
DOI: 10.1007/s00418-021-02024-6 -
Trends in Cell Biology Jan 1998For the Golgi apparatus to perform its various unique roles it must maintain a population of resident proteins. These residents include the enzymes that modify the... (Review)
Review
For the Golgi apparatus to perform its various unique roles it must maintain a population of resident proteins. These residents include the enzymes that modify the proteins and lipids passing through the Golgi, as well as the proteins involved in vesicle formation and protein sorting. For several of these residents, it has been possible to identify regions that are crucial for specifying a Golgi localization. Consideration of how these targeting domains could function has provided insights into the organization of the Golgi and its protein and lipid content.
Topics: Animals; Biological Transport; Golgi Apparatus; Humans; Membrane Proteins
PubMed: 9695801
DOI: 10.1016/s0962-8924(97)01197-5 -
FEBS Letters Dec 2009Plant Golgi bodies possess unique morphological and functional characteristics that are key to several biological and biotechnological processes, such as transport of... (Review)
Review
Plant Golgi bodies possess unique morphological and functional characteristics that are key to several biological and biotechnological processes, such as transport of the cell's building blocks to energy-rich compartments, including chloroplasts, storage vacuoles and a cellulosic cell wall. During the last decade it has become apparent that the plant Golgi apparatus has features that are remarkably different from other systems. Here we summarize the most recent findings on this organelle and we highlight pressing questions that are likely to drive the next 10 years of research on the plant Golgi apparatus.
Topics: Cell Division; Endoplasmic Reticulum; Golgi Apparatus; Plant Cells; Plant Proteins; Plants
PubMed: 19800330
DOI: 10.1016/j.febslet.2009.09.046 -
Traffic (Copenhagen, Denmark) Nov 2010The Golgi apparatus lies at the heart of the secretory pathway where it receives, modifies and sorts protein cargo to the proper intracellular or extracellular location.... (Review)
Review
The Golgi apparatus lies at the heart of the secretory pathway where it receives, modifies and sorts protein cargo to the proper intracellular or extracellular location. Although this secretory function is highly conserved throughout the eukaryotic kingdom, the structure of the Golgi complex is arranged very differently among species. In particular, Golgi membranes in vertebrate cells are integrated into a single compact entity termed the Golgi ribbon that is normally localized in the perinuclear area and in close vicinity to the centrosomes. This organization poses a challenge for cell division when the single Golgi ribbon needs to be partitioned into the two daughter cells. To ensure faithful inheritance in the progeny, the Golgi ribbon is divided in three consecutive steps in mitosis, namely disassembly, partitioning and reassembly. However, the structure of the Golgi ribbon is only present in higher animals and Golgi disassembly during mitosis is not ubiquitous in all organisms. Therefore, there must be unique reasons to build up the Golgi in this particular conformation and to preserve it over generations. In this review, we first highlight the diversity of the Golgi architecture in different organisms and revisit the concept of the Golgi ribbon. Following on, we discuss why the ribbon is needed and how it forms in vertebrate cells. Lastly, we conclude with likely purposes of mitotic ribbon disassembly and further propose mechanisms by which it regulates mitosis.
Topics: Animals; Golgi Apparatus; Humans; Interphase; Mitosis
PubMed: 21040294
DOI: 10.1111/j.1600-0854.2010.01114.x