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Current Opinion in Cell Biology Aug 2018Eukaryotic cells are organized into membrane-bound organelles. These organelles communicate with one another through vesicular trafficking pathways and membrane contact... (Review)
Review
Eukaryotic cells are organized into membrane-bound organelles. These organelles communicate with one another through vesicular trafficking pathways and membrane contact sites (MCSs). MCSs are sites of close apposition between two or more organelles that play diverse roles in the exchange of metabolites, lipids and proteins. Organelle interactions at MCSs also are important for organelle division and biogenesis. For example, the division of several organelles, including mitochondria and endosomes, seem to be regulated by contacts with the endoplasmic reticulum (ER). Moreover, the biogenesis of autophagosomes and peroxisomes involves contributions from the ER and multiple other cellular compartments. Thus, organelle-organelle interactions allow cells to alter the shape and activities of their membrane-bound compartments, allowing them to cope with different developmental and environmental conditions.
Topics: Animals; Eukaryotic Cells; Humans; Intracellular Membranes; Organelles; Protein Transport
PubMed: 30006038
DOI: 10.1016/j.ceb.2018.06.003 -
The FEBS Journal Nov 2022The migrasome is a newly discovered organelle produced by migrating cells. As cells migrate, long and thin retraction fibers are left in their wake. On these fibers, we... (Review)
Review
The migrasome is a newly discovered organelle produced by migrating cells. As cells migrate, long and thin retraction fibers are left in their wake. On these fibers, we discovered the production of a pomegranate-like structure, which we named migrasomes. The production of migrasomes is highly correlated with the migration of cells. Currently, it has been demonstrated the migrasomes exhibit three modes of action: release of signaling molecules through rupturing or leaking, carriers of damaged mitochondria, and lateral transfer of mRNA or proteins. In this review, we would like to discuss, in detail, the functions, mechanisms, and potential applications of this newly discovered cell organelle.
Topics: Cell Movement; Organelles; Mitochondria; Signal Transduction; Organelle Biogenesis
PubMed: 34492154
DOI: 10.1111/febs.16183 -
The Journal of Biological Chemistry May 2019Eukaryotic cells organize their intracellular components into organelles that can be membrane-bound or membraneless. A large number of membraneless organelles, including... (Review)
Review
Eukaryotic cells organize their intracellular components into organelles that can be membrane-bound or membraneless. A large number of membraneless organelles, including nucleoli, Cajal bodies, P-bodies, and stress granules, exist as liquid droplets within the cell and arise from the condensation of cellular material in a process termed liquid-liquid phase separation (LLPS). Beyond a mere organizational tool, concentrating cellular components into membraneless organelles tunes biochemical reactions and improves cellular fitness during stress. In this review, we provide an overview of the molecular underpinnings of the formation and regulation of these membraneless organelles. This molecular understanding explains emergent properties of these membraneless organelles and shines new light on neurodegenerative diseases, which may originate from disturbances in LLPS and membraneless organelles.
Topics: Cell Physiological Phenomena; Cytoplasm; Humans; Organelles
PubMed: 30045872
DOI: 10.1074/jbc.TM118.001192 -
Nature Jan 2014Mitochondria are one of the major ancient endomembrane systems in eukaryotic cells. Owing to their ability to produce ATP through respiration, they became a driving... (Review)
Review
Mitochondria are one of the major ancient endomembrane systems in eukaryotic cells. Owing to their ability to produce ATP through respiration, they became a driving force in evolution. As an essential step in the process of eukaryotic evolution, the size of the mitochondrial chromosome was drastically reduced, and the behaviour of mitochondria within eukaryotic cells radically changed. Recent advances have revealed how the organelle's behaviour has evolved to allow the accurate transmission of its genome and to become responsive to the needs of the cell and its own dysfunction.
Topics: Animals; Chromosome Segregation; Chromosomes; DNA, Mitochondrial; Dynamins; Endoplasmic Reticulum; Eukaryotic Cells; Genome, Mitochondrial; Humans; Mitochondria; Organelle Shape; Stress, Physiological
PubMed: 24429632
DOI: 10.1038/nature12985 -
Science (New York, N.Y.) Aug 2018Our textbook image of organelles has changed. Instead of revealing isolated cellular compartments, the picture now emerging shows organelles as largely interdependent... (Review)
Review
Our textbook image of organelles has changed. Instead of revealing isolated cellular compartments, the picture now emerging shows organelles as largely interdependent structures that can communicate through membrane contact sites (MCSs). MCSs are sites where opposing organelles are tethered but do not fuse. MCSs provide a hybrid location where the tool kits of two different organelles can work together to perform vital cellular functions, such as lipid and ion transfer, signaling, and organelle division. Here, we focus on MCSs involving the endoplasmic reticulum (ER), an organelle forming an extensive network of cisternae and tubules. We highlight how the dynamic ER network regulates a plethora of cellular processes through MCSs with various organelles and with the plasma membrane.
Topics: Animals; Calcium; Cell Membrane; Endoplasmic Reticulum; Endosomes; Humans; Lipid Droplets; Lipid Metabolism; Metabolic Networks and Pathways; Microscopy, Fluorescence; Mitochondria; Neurodegenerative Diseases; Peroxisomes; Vesicular Transport Proteins
PubMed: 30072511
DOI: 10.1126/science.aan5835 -
The Journal of Cell Biology Dec 2020Diverse pathogen- and damage-associated stresses drive inflammation via activation of the multimolecular NLRP3-inflammasome complex. How the effects of diverse stimuli... (Review)
Review
Diverse pathogen- and damage-associated stresses drive inflammation via activation of the multimolecular NLRP3-inflammasome complex. How the effects of diverse stimuli are integrated by the cell to regulate NLRP3 has been the subject of intense research, and yet an accepted unifying hypothesis for the control of NLRP3 remains elusive. Here, we review the literature on the effects of NLRP3-activating stimuli on subcellular organelles and conclude that a shared feature of NLRP3-activating stresses is an organelle dysfunction. In particular, we propose that the endosome may be more important than previously recognized as a signal-integrating hub for NLRP3 activation in response to many stimuli and may also link to the dysfunction of other organelles. In addition, NLRP3-inflammasome-activating stimuli trigger diverse posttranslational modifications of NLRP3 that are important in controlling its activation. Future research should focus on how organelles respond to specific NLRP3-activating stimuli, and how this relates to posttranslational modifications, to delineate the organellar control of NLRP3.
Topics: Animals; Humans; Inflammasomes; NLR Family, Pyrin Domain-Containing 3 Protein; Organelles; Protein Processing, Post-Translational; Signal Transduction; Stress, Physiological
PubMed: 33044555
DOI: 10.1083/jcb.202006194 -
The Yale Journal of Biology and Medicine Sep 2019Lipid droplets are cytosolic fat storage organelles present in most eukaryotic cells. Long regarded merely as inert fat reservoirs, they are now emerging as major... (Review)
Review
Lipid droplets are cytosolic fat storage organelles present in most eukaryotic cells. Long regarded merely as inert fat reservoirs, they are now emerging as major regulators of cellular metabolism. They act as hubs that coordinate the pathways of lipid uptake, distribution, storage, and use in the cell. Recent studies have revealed that they are also essential components of the cellular stress response. One of the hallmark characteristics of lipid droplets is their capacity to buffer excess lipids and to finely tune their subsequent release based on specific cellular requirements. This simple feature of lipid droplet biology, buffering and delayed release of lipids, forms the basis for their pleiotropic roles in the cellular stress response. In stressed cells, lipid droplets maintain energy and redox homeostasis and protect against lipotoxicity by sequestering toxic lipids into their neutral lipid core. Their mobility and dynamic interactions with mitochondria enable an efficient delivery of fatty acids for optimal energy production. Lipid droplets are also involved in the maintenance of membrane and organelle homeostasis by regulating membrane composition, preventing lipid peroxidation and removing damaged proteins and lipids. Finally, they also engage in a symbiotic relationship with autophagy and act as reservoirs of bioactive lipids that regulate inflammation and immunity. Thus, lipid droplets are central managers of lipid metabolism that function as safeguards against various types of cellular stress.
Topics: Animals; Energy Metabolism; Homeostasis; Humans; Lipid Droplets; Lipids; Organelles; Stress, Physiological
PubMed: 31543707
DOI: No ID Found -
Cell Research Jan 2015Cells communicate with each other through secreting and releasing proteins and vesicles. Many cells can migrate. In this study, we report the discovery of migracytosis,...
Cells communicate with each other through secreting and releasing proteins and vesicles. Many cells can migrate. In this study, we report the discovery of migracytosis, a cell migration-dependent mechanism for releasing cellular contents, and migrasomes, the vesicular structures that mediate migracytosis. As migrating cells move, they leave long tubular strands, called retraction fibers, behind them. Large vesicles, which contain numerous smaller vesicles, grow on the tips and intersections of retraction fibers. These fibers, which connect the vesicles with the main cell body, eventually break, and the vesicles are released into the extracellular space or directly taken up by surrounding cells. Since the formation of these vesicles is migration-dependent, we named them "migrasomes". We also found that cytosolic contents can be transported into migrasomes and released from the cell through migrasomes. We named this migration-dependent release mechanism "migracytosis".
Topics: Actins; Animals; Biological Transport; Cell Line; Cell Line, Tumor; Cell Movement; Cytoplasm; Humans; Mice; Organelles
PubMed: 25342562
DOI: 10.1038/cr.2014.135 -
Cell Jan 2004Genetic and biochemical analyses of the secretory pathway have produced a detailed picture of the molecular mechanisms involved in selective cargo transport between... (Review)
Review
Genetic and biochemical analyses of the secretory pathway have produced a detailed picture of the molecular mechanisms involved in selective cargo transport between organelles. This transport occurs by means of vesicular intermediates that bud from a donor compartment and fuse with an acceptor compartment. Vesicle budding and cargo selection are mediated by protein coats, while vesicle targeting and fusion depend on a machinery that includes the SNARE proteins. Precise regulation of these two aspects of vesicular transport ensures efficient cargo transfer while preserving organelle identity.
Topics: Animals; Biological Transport; Endoplasmic Reticulum; Golgi Apparatus; Humans; Membrane Fusion; Membrane Proteins; Models, Biological; Models, Molecular; Organelles; SNARE Proteins; Saccharomyces cerevisiae; Temperature; Vesicular Transport Proteins
PubMed: 14744428
DOI: 10.1016/s0092-8674(03)01079-1 -
Developmental Cell Oct 2020In eukaryotic cells, various membrane-bound organelles compartmentalize diverse cellular activities in a spatially and temporally controlled manner. Numerous... (Review)
Review
In eukaryotic cells, various membrane-bound organelles compartmentalize diverse cellular activities in a spatially and temporally controlled manner. Numerous membraneless organelles assembled via liquid-liquid phase separation (LLPS), known as condensates, also facilitate compartmentalization of cellular functions. Emerging evidence shows that these two organelle types interact in many biological processes. Membranes modulate the biogenesis and dynamics of phase-separated condensates by serving as assembly platforms or by forming direct contacts. Phase separation of membrane-associated proteins participates in various trafficking events, such as clustering of vesicles for temporally controlled fusion and storage, and transport of membraneless condensates on membrane-bound organelles. Phase separation also acts in cargo trafficking pathways by sorting and docking cargos for translocon-mediated transport across membranes, by shuttling cargos through the nuclear pore complex, and by triggering the formation of surrounding autophagosomes for delivery to lysosomes. The coordinated actions of membrane-bound and membraneless organelles ensure spatiotemporal control of various cellular functions.
Topics: Autophagosomes; Biology; Biophysical Phenomena; Cell Physiological Phenomena; Humans; Membranes; Organelles
PubMed: 32726575
DOI: 10.1016/j.devcel.2020.06.033