-
Results and Problems in Cell... 2019The Golgi apparatus is a central intracellular membrane-bound organelle with key functions in trafficking, processing, and sorting of newly synthesized membrane and... (Review)
Review
The Golgi apparatus is a central intracellular membrane-bound organelle with key functions in trafficking, processing, and sorting of newly synthesized membrane and secretory proteins and lipids. To best perform these functions, Golgi membranes form a unique stacked structure. The Golgi structure is dynamic but tightly regulated; it undergoes rapid disassembly and reassembly during the cell cycle of mammalian cells and is disrupted under certain stress and pathological conditions. In the past decade, significant amount of effort has been made to reveal the molecular mechanisms that regulate the Golgi membrane architecture and function. Here we review the major discoveries in the mechanisms of Golgi structure formation, regulation, and alteration in relation to its functions in physiological and pathological conditions to further our understanding of Golgi structure and function in health and diseases.
Topics: Animals; Biological Transport; Cell Cycle; Disease; Golgi Apparatus; Health; Humans; Intracellular Membranes; Stress, Physiological
PubMed: 31435807
DOI: 10.1007/978-3-030-23173-6_19 -
Seminars in Cell & Developmental Biology Nov 2020In eukaryotic cells, protein sorting is a highly regulated mechanism important for many physiological events. After synthesis in the endoplasmic reticulum and... (Review)
Review
In eukaryotic cells, protein sorting is a highly regulated mechanism important for many physiological events. After synthesis in the endoplasmic reticulum and trafficking to the Golgi apparatus, proteins sort to many different cellular destinations including the endolysosomal system and the extracellular space. Secreted proteins need to be delivered directly to the cell surface. Sorting of secreted proteins from the Golgi apparatus has been a topic of interest for over thirty years, yet there is still no clear understanding of the machinery that forms the post-Golgi carriers. Most evidence points to these post-Golgi carriers being tubular pleomorphic structures that bud from the -face of the Golgi. In this review, we present the background studies and highlight the key components of this pathway, we then discuss the machinery implicated in the formation of these carriers, their translocation across the cytosol, and their fusion at the plasma membrane.
Topics: Animals; Cell Membrane; Golgi Apparatus; Humans; Lipid Metabolism; Membrane Fusion; Protein Transport; Secretory Pathway
PubMed: 32317144
DOI: 10.1016/j.semcdb.2020.04.001 -
ELife Apr 2024Mapping proteins in and associated with the Golgi apparatus reveals how this cellular compartment emerges in budding yeast and progresses over time.
Mapping proteins in and associated with the Golgi apparatus reveals how this cellular compartment emerges in budding yeast and progresses over time.
Topics: Golgi Apparatus; Saccharomycetales
PubMed: 38629949
DOI: 10.7554/eLife.97430 -
Cell Structure and Function Aug 2019In research on cell biology, organelles have been a major unit of such analyses. Researchers have assumed that the inside of an organelle is almost uniform in regards to... (Review)
Review
In research on cell biology, organelles have been a major unit of such analyses. Researchers have assumed that the inside of an organelle is almost uniform in regards to its function, even though each organelle has multiple functions. However, we are now facing conundrums that cannot be resolved so long as we regard organelles as functionally uniform units. For instance, how can cells control the diverse patterns of glycosylation of various secretory proteins in the endoplasmic reticulum and Golgi in an orderly manner with high accuracy? Here, we introduce the novel concept of organelle zones as a solution; each organelle has functionally distinct zones, and zones in different organelles closely interact each other in order to perform complex cellular functions. This Copernican Revolution from organelle biology to organelle zone biology will drastically change and advance our thoughts about cells.Key words: organelle zone, contact site, ER stress, Golgi stress, organelle autoregulation.
Topics: Animals; Endoplasmic Reticulum; Golgi Apparatus; Humans; Organelles
PubMed: 31308351
DOI: 10.1247/csf.19010 -
Methods in Molecular Biology (Clifton,... 2023Sorting and transport of secretory and membrane proteins occur at the trans-Golgi network (TGN). Carriers of the TGN to the cell surface (CARTS) are one of the carriers...
Sorting and transport of secretory and membrane proteins occur at the trans-Golgi network (TGN). Carriers of the TGN to the cell surface (CARTS) are one of the carriers that mediate the transport of certain proteins from the TGN to the plasma membrane. Recent studies have shown that CARTS formation is dependent on membrane contact sites between the Golgi apparatus and the endoplasmic reticulum (ER). Here, we describe a method to visualize by fluorescence microscopy the formation of CARTS at the TGN. This method combines a reverse dimerization system for synchronized export from the ER of a CARTS-specific cargo, pancreatic adenocarcinoma upregulated factor, together with the halt of export from the TGN by a 20 °C block. Incubation of cells at 37 °C releases the 20 °C block and allows to monitor the formation of CARTS at the TGN. Finally, we also present a workflow to quantify CARTS formation using ImageJ software.
Topics: Humans; Adenocarcinoma; Pancreatic Neoplasms; trans-Golgi Network; Golgi Apparatus; Endoplasmic Reticulum; Protein Transport; Cell Membrane
PubMed: 36512238
DOI: 10.1007/978-1-0716-2639-9_34 -
Cells Sep 2020Conventional protein secretion in eukaryotic cells occurs via vesicular trafficking of proteins that are first targeted to the endoplasmic reticulum (ER), through the...
Conventional protein secretion in eukaryotic cells occurs via vesicular trafficking of proteins that are first targeted to the endoplasmic reticulum (ER), through the Golgi apparatus, and subsequently routed to the plasma membrane (PM), where membrane proteins take up residence while luminal proteins are released extracellularly [...].
Topics: Animals; Cell Membrane; Endoplasmic Reticulum; Fungi; Golgi Apparatus; Humans; Membrane Proteins; Plants; Protein Transport
PubMed: 32882862
DOI: 10.3390/cells9092009 -
Current Biology : CB Apr 2018Muschalik and Munro introduce golgins and their roles as vesicle tethers and scaffolds at the Golgi. (Review)
Review
Muschalik and Munro introduce golgins and their roles as vesicle tethers and scaffolds at the Golgi.
Topics: Animals; Autoantigens; Biological Evolution; Evolution, Molecular; Golgi Apparatus; Golgi Matrix Proteins; Humans; Mammals; Membrane Proteins
PubMed: 29689216
DOI: 10.1016/j.cub.2018.01.006 -
Nature Communications Sep 2023Abnormal distribution of cellular cholesterol is associated with numerous diseases, including cardiovascular and neurodegenerative diseases. Regulated transport of...
Abnormal distribution of cellular cholesterol is associated with numerous diseases, including cardiovascular and neurodegenerative diseases. Regulated transport of cholesterol is critical for maintaining its proper distribution in the cell, yet the underlying mechanisms remain unclear. Here, we show that lipid transfer proteins, namely ORP9, OSBP, and GRAMD1s/Asters (GRAMD1a/GRAMD1b/GRAMD1c), control non-vesicular cholesterol transport at points of contact between the ER and the trans-Golgi network (TGN), thereby maintaining cellular cholesterol distribution. ORP9 localizes to the TGN via interaction between its tandem α-helices and ORP10/ORP11. ORP9 extracts PI4P from the TGN to prevent its overaccumulation and suppresses OSBP-mediated PI4P-driven cholesterol transport to the Golgi. By contrast, GRAMD1s transport excess cholesterol from the Golgi to the ER, thereby preventing its build-up. Cells lacking ORP9 exhibit accumulation of cholesterol at the Golgi, which is further enhanced by additional depletion of GRAMD1s with major accumulation in the plasma membrane. This is accompanied by chronic activation of the SREBP-2 signalling pathway. Our findings reveal the importance of regulated lipid transport at ER-Golgi contacts for maintaining cellular cholesterol distribution and homeostasis.
Topics: Mitochondrial Membranes; Golgi Apparatus; trans-Golgi Network; Biological Transport; Cholesterol
PubMed: 37735529
DOI: 10.1038/s41467-023-41213-w -
ELife Nov 2023A receptor protein called TGN46 has an important role in sorting secretory proteins into vesicles going to different destinations inside cells.
A receptor protein called TGN46 has an important role in sorting secretory proteins into vesicles going to different destinations inside cells.
Topics: trans-Golgi Network; Proteins; Protein Transport; Golgi Apparatus; Secretory Vesicles
PubMed: 37997893
DOI: 10.7554/eLife.93490 -
International Journal of Molecular... Apr 2023Today, the future paradigm of intracellular transport could be based on four competing models, namely the vesicular model, the cisterna maturation-progression model, the...
Today, the future paradigm of intracellular transport could be based on four competing models, namely the vesicular model, the cisterna maturation-progression model, the diffusion model, and the kiss-and-run model [...].
Topics: Golgi Apparatus; Biological Transport; Diffusion; Intracellular Membranes
PubMed: 37108712
DOI: 10.3390/ijms24087549