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Microfilament
Microfilaments, also called actin filaments, are protein filaments in the cytoplasm of eukaryotic cells that form part of the cytoskeleton. They are primarily composed of polymers of actin, but are modified by and interact with numerous other proteins in the cell. Microfilaments are usually about 7 nm in diameter and made up of two strands of actin. Microfilament functions include cytokinesis, amoeboid movement, cell motility, changes in cell shape, endocytosis and exocytosis, cell contractility, and mechanical stability. Microfilaments are flexible and relatively strong, resisting buckling by multi-piconewton compressive forces and filament fracture by nanonewton tensile forces. In inducing cell motility, one end of the actin filament elongates while the other end contracts, presumably by myosin II molecular motors. Additionally, they function as part of actomyosin-driven contractile molecular motors, wherein the thin filaments serve as tensile platforms for myosin's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Filament
In biology, a protein filament is a long chain of protein monomers, such as those found in hair, muscle, or in flagella. Protein filaments form together to make the cytoskeleton of the cell. They are often bundled together to provide support, strength, and rigidity to the cell. When the filaments are packed up together, they are able to form three different cellular parts. The three major classes of protein filaments that make up the cytoskeleton include: actin filaments, microtubules and intermediate filaments. Cellular types Microfilaments Compared to the other parts of the cytoskeletons, the microfilaments contain the thinnest filaments, with a diameter of approximately 7 nm. Microfilaments are part of the cytoskeleton that are composed of protein called actin. Two strands of actin intertwined together form a filamentous structure allowing for the movement of motor proteins. Microfilaments can either occur in the monomeric G-actin or filamentous F-actin. Microfilament ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoskeleton
The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is composed of similar proteins in the various organisms. It is composed of three main components: microfilaments, intermediate filaments, and microtubules, and these are all capable of rapid growth and or disassembly depending on the cell's requirements. Cytoskeleton can perform many functions. Its primary function is to give the cell its shape and mechanical resistance to deformation, and through association with extracellular connective tissue and other cells it stabilizes entire tissues. The cytoskeleton can also contract, thereby deforming the cell and the cell's environment and allowing cells to migrate. Moreover, it is involved in many cell signaling pathways and in the uptake of extracellular material ( endocytosis), the segregation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actin
Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of over 100 μM; its mass is roughly 42 kDa, with a diameter of 4 to 7 nm. An actin protein is the monomeric subunit of two types of filaments in cells: microfilaments, one of the three major components of the cytoskeleton, and thin filaments, part of the contractile apparatus in muscle cells. It can be present as either a free monomer called G-actin (globular) or as part of a linear polymer microfilament called F-actin (filamentous), both of which are essential for such important cellular functions as the mobility and contraction of cells during cell division. Actin participates in many important cellular processes, including muscle contraction, cell motility, cell division and cytokinesis, vesicle and organelle mov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exocytosis
Exocytosis is a term for the active transport process that transports large molecules from cell to the extracellular area. Hormones, proteins and neurotransmitters are examples of large molecules that can be transported out of the cell. Exocytosis is a crucial transport mechanism that enables polar molecules to flow through the cell membranes’ hydrophobic lipid bilayer. The transport process is essential to hormone secretion, immune response and neurotransmission. Both prokaryotes and eukaryotes undergo exocytosis. Prokaryotes secrete molecules and cellular waste through translocons that are localized to the cell membrane. In addition, they secrete molecules to other cells through specialized organs. Eukaryotes rely on multiple cellular processes to perform the exocytosis process. Eukaryotes have several organelles and a nucleus in the cytoplasm that are connected through multiple transport routes, that is formally known as the secretory pathway. This is a complex pathway with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diameter
In geometry, a diameter of a circle is any straight line segment that passes through the centre of the circle and whose endpoints lie on the circle. It can also be defined as the longest Chord (geometry), chord of the circle. Both definitions are also valid for the diameter of a sphere. In more modern usage, the length d of a diameter is also called the diameter. In this sense one speaks of diameter rather than diameter (which refers to the line segment itself), because all diameters of a circle or sphere have the same length, this being twice the radius r. :d = 2r \qquad\text\qquad r = \frac. The word "diameter" is derived from (), "diameter of a circle", from (), "across, through" and (), "measure". It is often abbreviated \text, \text, d, or \varnothing. Constructions With straightedge and compass, a diameter of a given circle can be constructed as the perpendicular bisector of an arbitrary chord. Drawing two diameters in this way can be used to locate the center of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brunó Ferenc Straub
Brunó Ferenc Straub (5 January 1914 in Nagyvárad, Austria-Hungary (now Oradea, Romania) – 15 February 1996) was a biochemist. As a young scholar he was a research assistant of Albert Szent-Györgyi at the University of Szeged, and subsequently worked at the Molteno Institute, Cambridge, UK. He was the first to obtain actin in a relatively pure state. He founded the Biological Research Centre in Szeged Szeged ( , ; see also #Etymology, other alternative names) is List of cities and towns of Hungary#Largest cities in Hungary, the third largest city of Hungary, the largest city and regional centre of the Southern Great Plain and the county seat .... He was the chairman of the Hungarian Presidential Council from 29 June 1988 to 23 October 1989. He proposed the theory of conformational selection in 1964, the same year the Monod–Wyman–Changeux model was proposed. References {{DEFAULTSORT:Straub, Bruno Ferenc 1914 births 1996 deaths People from Oradea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hugh Huxley
Hugh Esmor Huxley (25 February 1924 – 25 July 2013) was a British molecular biologist who made important discoveries in the physiology of muscle. He was a graduate in physics from Christ's College, Cambridge. However, his education was interrupted for five years by the Second World War, during which he served in the Royal Air Force. His contribution to development of radar earned him an MBE. Huxley was the first PhD student of Laboratory of Molecular Biology of the Medical Research Council at Cambridge, where he worked on X-ray diffraction studies on muscle fibres. In the 1950s he was one of the first to use electron microscopy to study biological specimens. During his postdoctoral at Massachusetts Institute of Technology, he, with fellow researcher Jean Hanson, discovered the underlying principle of muscle movement, popularised as the sliding filament theory in 1954. After 15 years of research, he proposed the "swinging cross-bridge hypothesis" in 1969, which became mode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actin-binding Protein
Actin-binding proteins (also known as ABPs) are proteins that bind to actin. This may mean ability to bind actin monomers, or polymers, or both. Many actin-binding proteins, including α-actinin, β-spectrin, dystrophin, utrophin and fimbrin, do this through the actin-binding calponin homology domain. This is a list of actin-binding proteins in alphabetical order. 0–9 * 25kDa * 25kDa ABP from aorta * 30akDA * 30bkDa * 34kDA * 45kDa * 110 kD dimer ABP * 110 kD ( Drebrin) * p53 * p58gag * p185neu * p116rip A * a-actinin * Abl * ABLIM *Actin-Interacting MAPKKK Ssk2p * ABP120 * ABP140 * Abp1p * ABP280 ( Filamin) * ABP50 (EF-1a) * Acan 125 (Carmil) * ActA * Actibind *Actin * Actinfilin * Actinogelin * Actin-regulating kinases * Actin-Related Proteins * Actobindin * Actolinkin * Actopaxin * Actophorin * Acumentin (= L- plastin) * Adducin * ADF/Cofilin * Adseverin (scinderin) * Afadin * AFAP-110 * Affixin * Aginactin * AIP1 * Aldolase * Angiogenin * Anillin * Annexins * Ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanometer
330px, Different lengths as in respect to the Molecule">molecular scale. The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm), or nanometer (American spelling Despite the various list of dialects of English, English dialects spoken from country to country and within different regions of the same country, there are only slight regional variations in English orthography, the two most notable variati ...), is a units of measurement, unit of length in the International System of Units (SI), equal to one billionth (short scale) or one thousand million (long scale) of a metre, meter (0.000000001 m) and to 1000 picometres. One nanometre can be expressed in scientific notation as 1 × 10−9 m and as m. History The nanometre was formerly known as the "''millimicrometre''" – or, more commonly, the "''millimicron''" for short – since it is of a micrometre, micrometer. It was often de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MEF Microfilaments
MEF may stand for: Government * Mission Essential Functions - critical operations of the US government in the face of unexpected disruption Military * Malaita Eagle Force, a militant organization originating in the island of Malaita in the Solomon Islands * Marine Expeditionary Force (MEF), one of the major deployable subdivisions of the United States Marine Corps; see 1st Marine Expeditionary Force, 2nd Marine Expeditionary Force, 3rd Marine Expeditionary Force * Mediterranean Expeditionary Force * Mesopotamian Expeditionary Force during the First World War World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ... Organizations * Mahratta Education Fund, Indian non-profit organisation * Major Economies Forum on Energy and Climate Change * Media Education Foundation * MEF Inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymers
A polymer () is a substance or material that consists of very large molecules, or macromolecules, that are constituted by many repeating subunits derived from one or more species of monomers. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. Polymers are studied in the fields of polymer science (which includes polymer chemistry and polymer p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudopod
A pseudopod or pseudopodium (: pseudopods or pseudopodia) is a temporary arm-like projection of a eukaryotic cell membrane that is emerged in the direction of movement. Filled with cytoplasm, pseudopodia primarily consist of actin filaments and may also contain microtubules and intermediate filaments. Pseudopods are used for motility and ingestion. They are often found in amoebas. Different types of pseudopodia can be classified by their distinct appearances. Lamellipodia are broad and thin. Filopodia are slender, thread-like, and are supported largely by microfilaments. Lobopodia are bulbous and amoebic. Reticulopodia are complex structures bearing individual pseudopodia which form irregular nets. Axopodia are the phagocytosis type with long, thin pseudopods supported by complex microtubule arrays enveloped with cytoplasm; they respond rapidly to physical contact. Generally, several pseudopodia arise from the surface of the body, (''polypodial'', for example, '' Amoeba p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
