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Current Biology : CB Aug 2014
Topics: Actin Cytoskeleton; Cell Biology; France; History, 20th Century; History, 21st Century; Molecular Biology; Morphogenesis; United States
PubMed: 25237695
DOI: 10.1016/j.cub.2014.06.007 -
International Journal of Molecular... Oct 2021The plasma membrane protects the eukaryotic cell from its surroundings and is essential for cell viability; thus, it is crucial that membrane disruptions are repaired... (Review)
Review
The plasma membrane protects the eukaryotic cell from its surroundings and is essential for cell viability; thus, it is crucial that membrane disruptions are repaired quickly to prevent immediate dyshomeostasis and cell death. Accordingly, cells have developed efficient repair mechanisms to rapidly reseal ruptures and reestablish membrane integrity. The cortical actin cytoskeleton plays an instrumental role in both plasma membrane resealing and restructuring in response to damage. Actin directly aids membrane repair or indirectly assists auxiliary repair mechanisms. Studies investigating single-cell wound repair have often focused on the recruitment and activation of specialized repair machinery, despite the undeniable need for rapid and dynamic cortical actin modulation; thus, the role of the cortical actin cytoskeleton during wound repair has received limited attention. This review aims to provide a comprehensive overview of membrane repair mechanisms directly or indirectly involving cortical actin cytoskeletal remodeling.
Topics: Actin Cytoskeleton; Animals; Cell Membrane; Cell Physiological Phenomena; Humans; Single-Cell Analysis; Wound Healing
PubMed: 34639226
DOI: 10.3390/ijms221910886 -
The Journal of Medical Investigation :... 2017The adherens junction (AJ) is a cadherin-based and actin filament associated cell-to-cell junction. AJs can contribute to tissue morphogenesis and homeostasis and their... (Review)
Review
The adherens junction (AJ) is a cadherin-based and actin filament associated cell-to-cell junction. AJs can contribute to tissue morphogenesis and homeostasis and their association with actin filaments is crucial for the functions. There are three types of AJs in terms of the mode of actin filament/AJ association. Among many actin-binding proteins associated with AJs, α-catenin is one of the most important actin filament/AJ linkers that functions in all types of AJs. Although α-catenin in cadherin-catenin complex appears to bind to actin filaments within cells, it fails to bind to actin filaments in vitro mysteriously. Recent report revealed that α-catenin in the complex can bind to actin filaments in vitro when forces are applied to the filament. In addition to force-sensitive vinculin binding, α-catenin has another force-sensitive property of actin filament-binding. Elucidation of its significance and the molecular mechanism is indispensable for understanding AJ formation and maintenance during tissue morphogenesis, function and repair. J. Med. Invest. 64: 14-19, February, 2017.
Topics: Actin Cytoskeleton; Actins; Adherens Junctions; Animals; Humans; Protein Binding; Protein Interaction Domains and Motifs; alpha Catenin
PubMed: 28373611
DOI: 10.2152/jmi.64.14 -
Trends in Cell Biology Oct 2014The actin cytoskeleton assembles into branched networks or bundles to generate mechanical force for critical cellular processes such as establishment of polarity,... (Review)
Review
The actin cytoskeleton assembles into branched networks or bundles to generate mechanical force for critical cellular processes such as establishment of polarity, adhesion, and migration. Stress fibers (SFs) are contractile actomyosin structures that physically couple to the extracellular matrix through integrin-based focal adhesions (FAs), thereby transmitting force into and across the cell. Recently, LIN-11, Isl1, and MEC-3 (LIM) domain proteins have been implicated in mediating this cytoskeletal mechanotransduction. Among the more well-studied LIM domain adapter proteins is zyxin, a dynamic component of both FAs and SFs. Here we discuss recent research detailing the mechanisms by which SFs adjust their structure and composition to balance mechanical forces and suggest ways that zyxin and other LIM domain proteins mediate mechanoresponse.
Topics: Actin Cytoskeleton; Animals; Humans; LIM-Homeodomain Proteins; Mechanotransduction, Cellular; Stress, Mechanical
PubMed: 24933506
DOI: 10.1016/j.tcb.2014.04.009 -
Journal of Molecular and Cellular... May 2010The Frank-Starling law of the heart describes the interrelationship between end-diastolic volume and cardiac ejection volume, a regulatory system that operates on a... (Review)
Review
The Frank-Starling law of the heart describes the interrelationship between end-diastolic volume and cardiac ejection volume, a regulatory system that operates on a beat-to-beat basis. The main cellular mechanism that underlies this phenomenon is an increase in the responsiveness of cardiac myofilaments to activating Ca(2+) ions at a longer sarcomere length, commonly referred to as myofilament length-dependent activation. This review focuses on what molecular mechanisms may underlie myofilament length dependency. Specifically, the roles of inter-filament spacing, thick and thin filament based regulation, as well as sarcomeric regulatory proteins are discussed. Although the "Frank-Starling law of the heart" constitutes a fundamental cardiac property that has been appreciated for well over a century, it is still not known in muscle how the contractile apparatus transduces the information concerning sarcomere length to modulate ventricular pressure development.
Topics: Actin Cytoskeleton; Animals; Heart; Humans; Models, Biological; Myocardial Contraction; Sarcomeres; Troponin I
PubMed: 20053351
DOI: 10.1016/j.yjmcc.2009.12.017 -
Frontiers in Immunology 2020A growing number of monogenic immune-mediated diseases have been related to genes involved in pathways of actin cytoskeleton remodeling. Increasing evidences associate... (Review)
Review
A growing number of monogenic immune-mediated diseases have been related to genes involved in pathways of actin cytoskeleton remodeling. Increasing evidences associate cytoskeleton defects to autoinflammatory diseases and primary immunodeficiencies. We reviewed the pathways of actin cytoskeleton remodeling in order to identify inflammatory and immunological manifestations associated to pathological variants. We list more than twenty monogenic diseases, ranging from pure autoinflammatory conditions as familial Mediterranean fever, mevalonate kinase deficiency and PAPA syndrome, to classic and novel primary immunodeficiencies as Wiskott-Aldrich syndrome and DOCK8 deficiency, characterized by the presence of concomitant inflammatory and autoimmune manifestations, such as vasculitis and cytopenia, to severe and recurrent infections. We classify these disorders according to the role of the mutant gene in actin cytoskeleton remodeling, and in particular as disorders of transcription, elongation, branching and activation of actin. This expanding field of rare immune disorders offers a new perspective to all immunologists to better understand the physiological and pathological role of actin cytoskeleton in cells of innate and adaptive immunity.
Topics: Actin Cytoskeleton; Animals; Autoimmunity; Genetic Predisposition to Disease; Humans; Immunologic Deficiency Syndromes; Inflammation; Mutation; Phenotype; Signal Transduction
PubMed: 33488606
DOI: 10.3389/fimmu.2020.604206 -
International Journal of Molecular... Feb 2022Actin-associated proteins (AAPs) act on monomeric globular actin (G-actin) and polymerized filamentous actin (F-actin) to regulate their dynamics and architectures which... (Review)
Review
Actin-associated proteins (AAPs) act on monomeric globular actin (G-actin) and polymerized filamentous actin (F-actin) to regulate their dynamics and architectures which ultimately control cell movement, shape change, division; organelle localization and trafficking. Actin-binding proteins (ABPs) are a subset of AAPs. Since actin was discovered as a myosin-activating protein (hence named actin) in 1942, the protein has also been found to be expressed in non-muscle cells, and numerous AAPs continue to be discovered. This review article lists all of the AAPs discovered so far while also allowing readers to sort the list based on the names, sizes, functions, related human diseases, and the dates of discovery. The list also contains links to the UniProt and Protein Atlas databases for accessing further, related details such as protein structures, associated proteins, subcellular localization, the expression levels in cells and tissues, mutations, and pathology. Because the actin cytoskeleton is involved in many pathological processes such as tumorigenesis, invasion, and developmental diseases, small molecules that target actin and AAPs which hold potential to treat these diseases are also listed.
Topics: Actin Cytoskeleton; Actins; Carcinogenesis; Cell Movement; Humans; Microfilament Proteins; Small Molecule Libraries
PubMed: 35216237
DOI: 10.3390/ijms23042118 -
Annual Review of Biophysics Jul 2016Cells contain elaborate and interconnected networks of protein polymers, which make up the cytoskeleton. The cytoskeleton governs the internal positioning and movement... (Review)
Review
Cells contain elaborate and interconnected networks of protein polymers, which make up the cytoskeleton. The cytoskeleton governs the internal positioning and movement of vesicles and organelles and controls dynamic changes in cell polarity, shape, and movement. Many of these processes require tight control of the size and shape of cytoskeletal structures, which is achieved despite rapid turnover of their molecular components. Here we review mechanisms by which cells control the size of filamentous cytoskeletal structures, from the point of view of simple quantitative models that take into account stochastic dynamics of their assembly and disassembly. Significantly, these models make experimentally testable predictions that distinguish different mechanisms of length control. Although the primary focus of this review is on cytoskeletal structures, we believe that the broader principles and mechanisms discussed herein will apply to a range of other subcellular structures whose sizes are tightly controlled and are linked to their functions.
Topics: Actin Cytoskeleton; Animals; Cytoskeleton; Microtubules
PubMed: 27145876
DOI: 10.1146/annurev-biophys-070915-094206 -
Current Biology : CB Feb 2012The field of mechanobiology has witnessed an explosive growth over the past several years as interest has greatly increased in understanding how mechanical forces are... (Review)
Review
The field of mechanobiology has witnessed an explosive growth over the past several years as interest has greatly increased in understanding how mechanical forces are transduced by cells and how cells migrate, adhere and generate traction. Actin, a highly abundant and anomalously conserved protein, plays a large role in forming the dynamic cytoskeleton that is so essential for cell form, motility and mechanosensitivity. While the actin filament (F-actin) has been viewed as dynamic in terms of polymerization and depolymerization, new results suggest that F-actin itself may function as a highly dynamic tension sensor. This property may help explain the unusual conservation of actin's sequence, as well as shed further light on actin's essential role in structures from sarcomeres to stress fibers.
Topics: Actin Cytoskeleton; Actins; Mechanotransduction, Cellular; Models, Molecular; Protein Structure, Tertiary
PubMed: 22321312
DOI: 10.1016/j.cub.2011.12.010 -
Journal of Biochemistry Apr 2021The nucleus is a very complex organelle present in eukaryotic cells. Having the crucial task to safeguard, organize and manage the genetic information, it must tightly... (Review)
Review
The nucleus is a very complex organelle present in eukaryotic cells. Having the crucial task to safeguard, organize and manage the genetic information, it must tightly control its molecular constituents, its shape and its internal architecture at any given time. Despite our vast knowledge of nuclear cell biology, much is yet to be unravelled. For instance, only recently we came to appreciate the existence of a dynamic nuclear cytoskeleton made of actin filaments that regulates processes such as gene expression, DNA repair and nuclear expansion. This suggests further exciting discoveries ahead of us. Modern cell biologists embrace a new methodology relying on precise perturbations of cellular processes that require a reversible, highly spatially confinable, rapid, inexpensive and tunEable external stimulus: light. In this review, we discuss how optogenetics, the state-of-the-art technology that uses genetically encoded light-sensitive proteins to steer biological processes, can be adopted to specifically investigate nuclear cell biology.
Topics: Actin Cytoskeleton; Animals; Cell Biology; Cell Nucleus; Cytoskeleton; Gene Expression Regulation; Humans; Light; Optogenetics; Protein Engineering; Protein Transport
PubMed: 33245128
DOI: 10.1093/jb/mvaa139