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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 -
Science (New York, N.Y.) Aug 2018Apoptosis is an evolutionarily conserved form of programmed cell death critical for development and tissue homeostasis in animals. The apoptotic control network includes...
Apoptosis is an evolutionarily conserved form of programmed cell death critical for development and tissue homeostasis in animals. The apoptotic control network includes several positive feedback loops that may allow apoptosis to spread through the cytoplasm in self-regenerating trigger waves. We tested this possibility in cell-free egg extracts and observed apoptotic trigger waves with speeds of ~30 micrometers per minute. Fractionation and inhibitor studies implicated multiple feedback loops in generating the waves. Apoptotic oocytes and eggs exhibited surface waves with speeds of ~30 micrometers per minute, which were tightly correlated with caspase activation. Thus, apoptosis spreads through trigger waves in both extracts and intact cells. Our findings show how apoptosis can spread over large distances within a cell and emphasize the general importance of trigger waves in cell signaling.
Topics: Animals; Apoptosis; Cell-Free System; Cytoplasm; Oocytes; Signal Transduction; Xenopus laevis
PubMed: 30093599
DOI: 10.1126/science.aah4065 -
Developmental Cell Jan 2021Cytoplasm is a gel-like crowded environment composed of various macromolecules, organelles, cytoskeletal networks, and cytosol. The structure of the cytoplasm is highly... (Review)
Review
Cytoplasm is a gel-like crowded environment composed of various macromolecules, organelles, cytoskeletal networks, and cytosol. The structure of the cytoplasm is highly organized and heterogeneous due to the crowding of its constituents and their effective compartmentalization. In such an environment, the diffusive dynamics of the molecules are restricted, an effect that is further amplified by clustering and anchoring of molecules. Despite the crowded nature of the cytoplasm at the microscopic scale, large-scale reorganization of the cytoplasm is essential for important cellular functions, such as cell division and polarization. How such mesoscale reorganization of the cytoplasm is achieved, especially for large cells such as oocytes or syncytial tissues that can span hundreds of micrometers in size, is only beginning to be understood. In this review, we will discuss recent advances in elucidating the molecular, cellular, and biophysical mechanisms by which the cytoskeleton drives cytoplasmic reorganization across different scales, structures, and species.
Topics: Animals; Cytoplasm; Cytoskeleton; Cytosol; Humans; Mechanotransduction, Cellular; Multiprotein Complexes; Organelles
PubMed: 33321104
DOI: 10.1016/j.devcel.2020.12.002 -
Molecular Cell Mar 2023Mitochondria have emerged as signaling organelles with roles beyond their well-established function in generating ATP and metabolites for macromolecule synthesis....
Mitochondria have emerged as signaling organelles with roles beyond their well-established function in generating ATP and metabolites for macromolecule synthesis. Healthy mitochondria integrate various physiologic inputs and communicate signals that control cell function or fate as well as adaptation to stress. Dysregulation of these mitochondrial signaling networks are linked to pathology. Here we outline a few modes of signaling between the mitochondrion and the cytoplasm. To view this SnapShot, open or download the PDF.
Topics: Mitochondria; Signal Transduction; Cytoplasm; Organelles; Acclimatization
PubMed: 36931250
DOI: 10.1016/j.molcel.2023.01.008 -
Nature Reviews. Molecular Cell Biology Mar 2021Biomolecular condensates are found throughout eukaryotic cells, including in the nucleus, in the cytoplasm and on membranes. They are also implicated in a wide range of... (Review)
Review
Biomolecular condensates are found throughout eukaryotic cells, including in the nucleus, in the cytoplasm and on membranes. They are also implicated in a wide range of cellular functions, organizing molecules that act in processes ranging from RNA metabolism to signalling to gene regulation. Early work in the field focused on identifying condensates and understanding how their physical properties and regulation arise from molecular constituents. Recent years have brought a focus on understanding condensate functions. Studies have revealed functions that span different length scales: from molecular (modulating the rates of chemical reactions) to mesoscale (organizing large structures within cells) to cellular (facilitating localization of cellular materials and homeostatic responses). In this Roadmap, we discuss representative examples of biochemical and cellular functions of biomolecular condensates from the recent literature and organize these functions into a series of non-exclusive classes across the different length scales. We conclude with a discussion of areas of current interest and challenges in the field, and thoughts about how progress may be made to further our understanding of the widespread roles of condensates in cell biology.
Topics: Animals; Biochemical Phenomena; Cell Physiological Phenomena; Cytoplasm; Eukaryotic Cells; Humans; Macromolecular Substances; Multiprotein Complexes; Organelles; Protein Aggregates
PubMed: 33169001
DOI: 10.1038/s41580-020-00303-z -
Annual Review of Cell and Developmental... Oct 2021The purpose of this review is to explore self-organizing mechanisms that pattern microtubules (MTs) and spatially organize animal cell cytoplasm, inspired by recent... (Review)
Review
The purpose of this review is to explore self-organizing mechanisms that pattern microtubules (MTs) and spatially organize animal cell cytoplasm, inspired by recent experiments in frog egg extract. We start by reviewing conceptual distinctions between self-organizing and templating mechanisms for subcellular organization. We then discuss self-organizing mechanisms that generate radial MT arrays and cell centers in the absence of centrosomes. These include autocatalytic MT nucleation, transport of minus ends, and nucleation from organelles such as melanosomes and Golgi vesicles that are also dynein cargoes. We then discuss mechanisms that partition the cytoplasm in syncytia, in which multiple nuclei share a common cytoplasm, starting with cytokinesis, when all metazoan cells are transiently syncytial. The cytoplasm of frog eggs is partitioned prior to cytokinesis by two self-organizing modules, protein regulator of cytokinesis 1 (PRC1)-kinesin family member 4A (KIF4A) and chromosome passenger complex (CPC)-KIF20A. Similar modules may partition longer-lasting syncytia, such as early embryos. We end by discussing shared mechanisms and principles for the MT-based self-organization of cellular units.
Topics: Animals; Centrosome; Cytokinesis; Cytoskeleton; Golgi Apparatus; Microtubules
PubMed: 34186005
DOI: 10.1146/annurev-cellbio-120319-025356 -
Biomolecules Oct 2022Mitochondria are semi-autonomous, membrane-bound organelles present in the cytoplasm of nearly all eukaryotic cells [...].
Mitochondria are semi-autonomous, membrane-bound organelles present in the cytoplasm of nearly all eukaryotic cells [...].
Topics: Humans; Mitochondria; Organelles; Cytoplasm; Eukaryotic Cells; Central Nervous System Diseases
PubMed: 36291623
DOI: 10.3390/biom12101414 -
Journal of Neuroscience Research Feb 2020Aging is a primary risk factor for fatal neurodegenerative disorders, yet the mechanisms underlying physiological healthy aging and pathological aging, and how these... (Review)
Review
Aging is a primary risk factor for fatal neurodegenerative disorders, yet the mechanisms underlying physiological healthy aging and pathological aging, and how these mechanisms can divert one scenario to the other, are not completely understood. In recent years, reports indicate that alterations in nucleocytoplasmic transport may be a hallmark of both healthy and pathological aging. In this review, I summarize recent evidence supporting this information, specifically focusing on the association between the nucleocytoplasmic transport and aging of the brain, indicating both common and case-specific mechanisms and their interplay, and pointing out alterations of these mechanisms as regulatory "switches" for the fate of the aging brain. Importantly, some of these alterations are intervenable druggable targets, paving the way to a future pharmacotherapeutic intervention.
Topics: Aging; Animals; Brain; Cell Nucleus; Cytoplasm; Humans; Neurodegenerative Diseases
PubMed: 31131478
DOI: 10.1002/jnr.24446 -
Transcription Nov 2023Eukaryotic cells rely upon dynamic, multifaceted regulation at each step of RNA biogenesis to maintain mRNA pools and ensure normal protein synthesis. Studies in budding... (Review)
Review
Eukaryotic cells rely upon dynamic, multifaceted regulation at each step of RNA biogenesis to maintain mRNA pools and ensure normal protein synthesis. Studies in budding yeast indicate a buffering phenomenon that preserves global mRNA levels through the reciprocal balancing of RNA synthesis rates and mRNA decay. In short, changes in transcription impact the efficiency of mRNA degradation and defects in either nuclear or cytoplasmic mRNA degradation are somehow sensed and relayed to control a compensatory change in mRNA transcription rates. Here, we review current views on molecular mechanisms that might explain this apparent bidirectional sensing process that ensures homeostasis of the stable mRNA pool.
Topics: RNA, Messenger; Transcription, Genetic; Cytoplasm; Homeostasis; RNA Stability
PubMed: 36843061
DOI: 10.1080/21541264.2023.2183684 -
FEMS Microbiology Reviews Jul 2023In living cells, the biochemical processes such as energy provision, molecule synthesis, gene expression, and cell division take place in a confined space where the...
In living cells, the biochemical processes such as energy provision, molecule synthesis, gene expression, and cell division take place in a confined space where the internal chemical and physical conditions are different from those in dilute solutions. The concentrations of specific molecules and the specific reactions and interactions vary for different types of cells, but a number of factors are universal and kept within limits, which we refer to as physicochemical homeostasis. For instance, the internal pH of many cell types is kept within the range of 7.0 to 7.5, the fraction of macromolecules occupies 15%-20% of the cell volume (also known as macromolecular crowding) and the ionic strength is kept within limits to prevent salting-in or salting-out effects. In this article we summarize the generic physicochemical properties of the cytoplasm of bacteria, how they are connected to the energy status of the cell, and how they affect biological processes (Fig. 1). We describe how the internal pH and proton motive force are regulated, how the internal ionic strength is kept within limits, what the impact of macromolecular crowding is on the function of enzymes and the interaction between molecules, how cells regulate their volume (and turgor), and how the cytoplasm is structured. Physicochemical homeostasis is best understood in Escherichia coli, but pioneering studies have also been performed in lactic acid bacteria.
Topics: Bacteria; Cytoplasm; Homeostasis; Macromolecular Substances
PubMed: 37336577
DOI: 10.1093/femsre/fuad033