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Mechanotaxis
Mechanotaxis refers to the directed movement of cell motility via mechanical cues (e.g., fluidic shear stress, substrate stiffness gradients, etc.). In response to fluidic shear stress, for example, cells have been shown to migrate in the direction of the fluid flow. Mechanotaxis is critical in many normal biological processes in animals, such as gastrulation, inflammation, and repair in response to a wound, as well as in mechanisms of diseases such as tumor metastasis. A subset of mechanotaxis - termed durotaxis - refers specifically to cell migration guided by gradients in substrate rigidity (i.e. stiffness). The observation that certain cell types seeded on a substrate rigidity gradient migrate up the gradient (i.e. in the direction of increasing substrate stiffness) was first reported by Lo et al. The primary method for creating rigidity gradients for cells (e.g., in biomaterials) consists of altering the degree of cross-linking in polymers to adjust substrate stiffness. Alte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plithotaxis
Plithotaxis, from the Greek word "πλήΘος", denotes a crowd, swarm, or throng. In collective cellular migration, plithotaxis is the tendency for each individual cell within a monolayer to migrate along the local orientation of the maximal principal stress, or equivalently, minimal intercellular shear stress.Tambe, D.T., Hardin, C., Angelini, T.E., Rajendran, K., Park, C.Y., Serra-Picamal, X., Zhou, E.H., Zaman, M.H., Butler, J.P., Weitz, D.A., Fredberg JJ, Trepat, X, Collective cell guidance by cooperative intercellular forces. ''Nature Materials'',10(6), 469-475, 2011, .Trepat, X, Fredberg, JJ. Plithotaxis and emergent dynamics in collective cellular migration. ''Trends in Cell Biology'' - 23 July 2011, . Plithotaxis requires force transmission across many cell-cell junctions and therefore is an emergent property of the cell group. Plithotaxis is found to hold at the level of both a subcellular grid point and an individual cell of a confluent monolayer, and the stresses must ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haptotaxis
Haptotaxis (from Greek ἅπτω (hapto, "touch, fasten") and τάξις (taxis, "arrangement, order")) is the directional motility or outgrowth of cells, e.g. in the case of axonal outgrowth, usually up a gradient of cellular adhesion sites or substrate-bound chemoattractants (the gradient of the chemoattractant being expressed or bound on a surface, in contrast to the classical model of chemotaxis, in which the gradient develops in a soluble fluid.). These gradients are naturally present in the extracellular matrix (ECM) of the body during processes such as angiogenesis or artificially present in biomaterials where gradients are established by altering the concentration of adhesion sites on a polymer substrate. Clinical Significance Haptotaxis plays a major role in the efficient healing of wounds. For example, when corneal integrity is compromised, epithelial cells quickly cover the damaged area by proliferation and migration (haptotaxis). In the corneal stroma, keratocytes wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durotaxis
Durotaxis is a form of cell migration in which cells are guided by rigidity gradients, which arise from differential structural properties of the extracellular matrix (ECM). Most normal cells migrate up rigidity gradients (in the direction of greater stiffness). History of durotaxis research The process of durotaxis requires a cell to actively sense the environment, process the mechanical stimulus, and execute a response. Originally, this was believed to be an emergent metazoan property, as the phenomenon requires a complex sensory loop that is dependent on the communication of many different cells. However, as the wealth of relevant scientific literature grew in the late 1980s and throughout the 1990s, it became apparent that single cells possess the ability to do the same. The first observations of durotaxis in isolated cells were that mechanical stimuli could cause the initiation and elongation of axons in the sensory and brain neurons of chicks and induce motility in previousl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemotaxis
Chemotaxis (from '' chemo-'' + ''taxis'') is the movement of an organism or entity in response to a chemical stimulus. Somatic cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemicals in their environment. This is important for bacteria to find food (e.g., glucose) by swimming toward the highest concentration of food molecules, or to flee from poisons (e.g., phenol). In multicellular organisms, chemotaxis is critical to early development (e.g., movement of sperm towards the egg during fertilization) and development (e.g., migration of neurons or lymphocytes) as well as in normal function and health (e.g., migration of leukocytes during injury or infection). In addition, it has been recognized that mechanisms that allow chemotaxis in animals can be subverted during cancer metastasis. The aberrant chemotaxis of leukocytes and lymphocytes also contribute to inflammatory diseases such as atherosclerosis, asthma, and arthr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemotaxis
Chemotaxis (from '' chemo-'' + ''taxis'') is the movement of an organism or entity in response to a chemical stimulus. Somatic cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemicals in their environment. This is important for bacteria to find food (e.g., glucose) by swimming toward the highest concentration of food molecules, or to flee from poisons (e.g., phenol). In multicellular organisms, chemotaxis is critical to early development (e.g., movement of sperm towards the egg during fertilization) and development (e.g., migration of neurons or lymphocytes) as well as in normal function and health (e.g., migration of leukocytes during injury or infection). In addition, it has been recognized that mechanisms that allow chemotaxis in animals can be subverted during cancer metastasis. The aberrant chemotaxis of leukocytes and lymphocytes also contribute to inflammatory diseases such as atherosclerosis, asthma, and arthr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haptotaxis
Haptotaxis (from Greek ἅπτω (hapto, "touch, fasten") and τάξις (taxis, "arrangement, order")) is the directional motility or outgrowth of cells, e.g. in the case of axonal outgrowth, usually up a gradient of cellular adhesion sites or substrate-bound chemoattractants (the gradient of the chemoattractant being expressed or bound on a surface, in contrast to the classical model of chemotaxis, in which the gradient develops in a soluble fluid.). These gradients are naturally present in the extracellular matrix (ECM) of the body during processes such as angiogenesis or artificially present in biomaterials where gradients are established by altering the concentration of adhesion sites on a polymer substrate. Clinical Significance Haptotaxis plays a major role in the efficient healing of wounds. For example, when corneal integrity is compromised, epithelial cells quickly cover the damaged area by proliferation and migration (haptotaxis). In the corneal stroma, keratocytes wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Durotaxis
Durotaxis is a form of cell migration in which cells are guided by rigidity gradients, which arise from differential structural properties of the extracellular matrix (ECM). Most normal cells migrate up rigidity gradients (in the direction of greater stiffness). History of durotaxis research The process of durotaxis requires a cell to actively sense the environment, process the mechanical stimulus, and execute a response. Originally, this was believed to be an emergent metazoan property, as the phenomenon requires a complex sensory loop that is dependent on the communication of many different cells. However, as the wealth of relevant scientific literature grew in the late 1980s and throughout the 1990s, it became apparent that single cells possess the ability to do the same. The first observations of durotaxis in isolated cells were that mechanical stimuli could cause the initiation and elongation of axons in the sensory and brain neurons of chicks and induce motility in previousl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planar Cell Polarity
Planar Cell Polarity (PCP) is the protein mediated signaling that coordinates the orientation of cells in a layer of epithelial tissue. In vertebrates, examples of mature PCP oriented tissue are the stereo-cilia bundles in the inner ear, motile cilia of the epithelium, and cell motility in epidermal wound healing. Additionally, PCP is known to be crucial to major developmental time points including coordinating convergent extension during gastrulation and coordinating cell behavior for neural tube closure. Cells orient themselves and their neighbors by establishing asymmetric expression of PCP components on opposing cell members within cells to establish and maintain the directionality of the cells. Some of these PCP components are transmembrane proteins which can proliferate the orientation signal to the surrounding cells. Table of Contents # Introduction # Table of Contents # History of Planar Cell Polarity (PCP) Research # Core Planar Cell Polarity Components # Canonical Vs. N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Adhesion Kinase
PTK2 protein tyrosine kinase 2 (PTK2), also known as focal adhesion kinase (FAK), is a protein that, in humans, is encoded by the ''PTK2'' gene. PTK2 is a focal adhesion-associated protein kinase involved in cellular adhesion (how cells stick to each other and their surroundings) and spreading processes (how cells move around). It has been shown that when FAK was blocked, breast cancer cells became less metastatic due to decreased mobility. Function The PTK2 gene encodes a cytosolic protein tyrosine kinase that is found concentrated in the focal adhesions that form among cells attaching to extracellular matrix constituents. The encoded protein is a member of the FAK subfamily of protein tyrosine kinases that included PYK2, but lacks significant sequence similarity to kinases from other subfamilies. It also includes a large FERM domain. With the exception of certain types of blood cells, most cells express FAK. FAK tyrosine kinase activity can be activated, which plays a key ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Crest
Neural crest cells are a temporary group of cells unique to vertebrates that arise from the embryonic ectoderm germ layer, and in turn give rise to a diverse cell lineage—including melanocytes, craniofacial cartilage and bone, smooth muscle, peripheral and enteric neurons and glia. After gastrulation, neural crest cells are specified at the border of the neural plate and the non-neural ectoderm. During neurulation, the borders of the neural plate, also known as the neural folds, converge at the dorsal midline to form the neural tube. Subsequently, neural crest cells from the roof plate of the neural tube undergo an epithelial to mesenchymal transition, delaminating from the neuroepithelium and migrating through the periphery where they differentiate into varied cell types. The emergence of neural crest was important in vertebrate evolution because many of its structural derivatives are defining features of the vertebrate clade. Underlying the development of neural crest is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integrin
Integrins are transmembrane receptors that facilitate cell-cell and cell-extracellular matrix (ECM) adhesion. Upon ligand binding, integrins activate signal transduction pathways that mediate cellular signals such as regulation of the cell cycle, organization of the intracellular cytoskeleton, and movement of new receptors to the cell membrane. The presence of integrins allows rapid and flexible responses to events at the cell surface (''e.g''. signal platelets to initiate an interaction with coagulation factors). Several types of integrins exist, and one cell generally has multiple different types on its surface. Integrins are found in all animals while integrin-like receptors are found in plant cells. Integrins work alongside other proteins such as cadherins, the immunoglobulin superfamily cell adhesion molecules, selectins and syndecans, to mediate cell–cell and cell–matrix interaction. Ligands for integrins include fibronectin, vitronectin, collagen and laminin. Stru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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