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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 -
Current Biology : CB Jul 2019In 1955, the biologist and Nobel Prize laureate Christian de Duve discovered that cells possess specialized organelles filled with hydrolytic enzymes and he called these...
In 1955, the biologist and Nobel Prize laureate Christian de Duve discovered that cells possess specialized organelles filled with hydrolytic enzymes and he called these organelles lysosomes. At the same time, electron microscopy studies by Novikoff and colleagues showed that intracellular dense bodies, which later turned out to be lysosomes, contain cytoplasmic components. Together, these groundbreaking observations revealed that cells can deliver cytoplasmic components to lysosomes for degradation. The hallmark of this degradative process, which de Duve called autophagy, is the formation of double-membrane-limited vesicles. Further morphological characterization of these vesicles (autophagosomes) revealed that they mainly contain bulk cytoplasm. Although this suggested that autophagy leads to a non-selective degradation of cytoplasmic material, de Duve anticipated that a regulated and selective type of this pathway must also exist. Today we know that, under normal conditions, macroautophagy is a highly selective pathway that sequesters damaged or superfluous material from the cytoplasm through the formation of double-membrane-limited autophagosomes. Upon fusion with lysosomes, the content of autophagosomes is degraded and the resulting building blocks are released into the cytoplasm. However, in response to cytotoxic stress or starvation, cells start to produce autophagosomes that capture bulk cytoplasm non-selectively. This stress response is essential for cells to survive adverse environmental conditions, whereas the selective sequestration of cargo is important to maintain cellular homeostasis.
Topics: Autophagosomes; Autophagy; Cytosol; Lysosomes; Macroautophagy
PubMed: 31336079
DOI: 10.1016/j.cub.2019.06.014 -
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 -
Heredity Jul 2022Most heritable information in eukaryotic cells is encoded in the nuclear genome, with inheritance patterns following classic Mendelian segregation. Genomes residing in... (Review)
Review
Most heritable information in eukaryotic cells is encoded in the nuclear genome, with inheritance patterns following classic Mendelian segregation. Genomes residing in the cytoplasm, however, prove to be a peculiar exception to this rule. Cytoplasmic genetic elements are generally maternally inherited, although there are several exceptions where these are paternally, biparentally or doubly-uniparentally inherited. In this review, we examine the diversity and peculiarities of cytoplasmically inherited genomes, and the broad evolutionary consequences that non-Mendelian inheritance brings. We first explore the origins of vertical transmission and uniparental inheritance, before detailing the vast diversity of cytoplasmic inheritance systems across Eukaryota. We then describe the evolution of genomic organisation across lineages, how this process has been shaped by interactions with the nuclear genome and population genetics dynamics. Finally, we discuss how both nuclear and cytoplasmic genomes have evolved to co-inhabit the same host cell via one of the longest symbiotic processes, and all the opportunities for intergenomic conflict that arise due to divergence in inheritance patterns. In sum, we cannot understand the evolution of eukaryotes without understanding hereditary symbiosis.
Topics: Cytoplasm; Eukaryota; Genome; Inheritance Patterns; Symbiosis
PubMed: 35525886
DOI: 10.1038/s41437-022-00540-2 -
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 -
The Journal of Physiology Jun 2014It is widely accepted that the crosstalk between naive nucleus and maternal factors deposited in the egg cytoplasm before zygotic genome activation is crucial for early... (Review)
Review
It is widely accepted that the crosstalk between naive nucleus and maternal factors deposited in the egg cytoplasm before zygotic genome activation is crucial for early development. This crosstalk may also exert some influence on later development. It is interesting to clarify the relative roles of the zygotic genome and the cytoplasmic factors in development. Cross-species nuclear transfer (NT) between two distantly related species provides a unique system to study the relative role and crosstalk between egg cytoplasm and zygotic nucleus in development. In this review, we will summarize the recent progress of cross-species NT, with emphasis on the cross-species NT in fish and the influence of cytoplasmic factors on development. Finally, we conclude that the developmental process and its evolution should be interpreted in a systemic way, rather than in a way that solely focuses on the role of the nuclear genome.
Topics: Animals; Cell Nucleus; Cloning, Organism; Cytoplasm; Genetic Engineering; Hybridization, Genetic; Ovum
PubMed: 24882819
DOI: 10.1113/jphysiol.2014.272138 -
Frontiers in Immunology 2023Eukaryotic cells are stimulated by external pressure such as that derived from heat shock, oxidative stress, nutrient deficiencies, or infections, which induce the... (Review)
Review
Eukaryotic cells are stimulated by external pressure such as that derived from heat shock, oxidative stress, nutrient deficiencies, or infections, which induce the formation of stress granules (SGs) that facilitates cellular adaptation to environmental pressures. As aggregated products of the translation initiation complex in the cytoplasm, SGs play important roles in cell gene expression and homeostasis. Infection induces SGs formation. Specifically, a pathogen that invades a host cell leverages the host cell translation machinery to complete the pathogen life cycle. In response, the host cell suspends translation, which leads to SGs formation, to resist pathogen invasion. This article reviews the production and function of SGs, the interaction between SGs and pathogens, and the relationship between SGs and pathogen-induced innate immunity to provide directions for further research into anti-infection and anti-inflammatory disease strategies.
Topics: Cytoplasmic Granules; Stress Granules; Cytoplasm; Oxidative Stress; Heat-Shock Response
PubMed: 37205103
DOI: 10.3389/fimmu.2023.1145346 -
Methods (San Diego, Calif.) Mar 2019The sequestration of DNA within the membrane-bound nucleus is a defining characteristic of eukaryotic cells. Replication and transcription are therefore restricted to...
The sequestration of DNA within the membrane-bound nucleus is a defining characteristic of eukaryotic cells. Replication and transcription are therefore restricted to the nucleus, however, the regulation of these events relies on cytoplasmic processes including protein synthesis and signal transduction pathways. Because a variety of cellular activities depend on nuclear transport, researchers from diverse fields have found it useful to examine the nuclear localization of proteins of interest. Here we present some important technical considerations for studying nuclear and cytoplasmic localization, and provide guidance for quantifying protein levels using fluorescence microscopy and ImageJ software. We include discussion of the use of regions of interest and image segmentation for quantification of protein localization. Nucleocytoplasmic transport is fundamentally important for controlling protein levels and activity in the nucleus or cytoplasm, and quantitative analysis can provide insight into how biological output is achieved.
Topics: Active Transport, Cell Nucleus; Cell Nucleus; Cytoplasm; Fluorescence; Humans; Microscopy, Fluorescence; Protein Transport; Signal Transduction
PubMed: 30419335
DOI: 10.1016/j.ymeth.2018.11.002 -
Blood Sep 2022
Topics: Cytoplasm; Cytosol; Ubiquitin-Activating Enzymes
PubMed: 36173661
DOI: 10.1182/blood.2022017560 -
Molecular Plant-microbe Interactions :... Jan 2020RNA granules are dynamic cellular foci that are widely spread in eukaryotic cells and play essential roles in cell growth and development, and immune and stress... (Review)
Review
RNA granules are dynamic cellular foci that are widely spread in eukaryotic cells and play essential roles in cell growth and development, and immune and stress responses. Different types of granules can be distinguished, each with a specific function and playing a role in, for example, RNA transcription, modification, processing, decay, translation, and arrest. By means of communication and exchange of (shared) components, they form a large regulatory network in cells. Viruses have been reported to interact with one or more of these either cytoplasmic or nuclear granules, and act either proviral, to enable and support viral infection and facilitate viral movement, or antiviral, protecting or clearing hosts from viral infection. This review describes an overview and recent progress on cytoplasmic and nuclear RNA granules and their interplay with virus infection, first in animal systems and as a prelude to the status and current developments on plant viruses, which have been less well studied on this thus far.
Topics: Animals; Cytoplasm; Cytoplasmic Granules; Plant Viruses; RNA
PubMed: 31415225
DOI: 10.1094/MPMI-06-19-0161-FI