subunits, which as part of the fiber are referred to as filamentous actin, or F actin. Each microfilament ... filament network. Microfilament associated proteins In non muscle cells, actin filaments are formed ... MeshName Microfilament proteins eMedicineDictionary Microfilament DorlandsDict five 000066329 Microfilament Cytoskeletal Proteins Category Cell biology Category Actin based structures bg ca Microfilament cs Mikrofilamentum cy Microffilament de Mikrofilamente es Microfilamento ... ja oc Microfilament pl Mikrofilamenty ru fi Mikrofilamentti ... more details
Actin depolymerizing factors are a family of microfilament proteins. ref MeshName Actin Depolymerizing Factors ref They are used to regulate actin assembly. ref name pmid9748225 cite journal author Didry D, Carlier MF, Pantaloni D title Synergy between actin depolymerizing factor cofilin and profilin in increasing actin filament turnover journal J. Biol. Chem. volume 273 issue 40 pages 25602 11 year 1998 month October pmid 9748225 doi 10.1074 jbc.273.40.25602 url http www.jbc.org cgi pmidlookup?view long&pmid 9748225 ref References reflist Cytoskeletal Proteins Category Proteins biochem stub ... more details
Tropomodulin is a protein which binds and caps the pointed end of actin minus end where there is Actin Adenosine diphosphate ADP , regulating the length of actin filaments in muscle and non muscle cells. It functions in the presence of tropomyosin and nebulin to inhibit microfilament elongation. Inhibition of tropomodulin capping activity leads to dramatic increase in thin filament length from its pointed end. ref Citation url http www.nature.com nature journal v377 n6544 abs 377083a0.html title Requirement of pointed end capping by tropomodulin to maintain actin filament length in embryonic accessdate 2009 04 10 ref Genes TMOD1 TMOD2 TMOD3 TMOD4 References reflist External links MeshName Tropomodulin Cytoskeletal Proteins Category Proteins protein stub es Tropomodulina ... more details
Actinin is a microfilament protein. ACTN1 Actinin is necessary for the attachment of actin filaments to the Z line s in skeletal muscle cells, and to the dense bodies in smooth muscle cells . The functional protein is an anti parallel protein dimer dimer , which cross links the thin filaments in adjacent sarcomeres , and therefore coordinated contractions between sarcomeres in the horizontal axis. The non sarcomeric actinins ACTN1 and ACTN4 are widely expressed. Both ends of the rod shaped actinin dimer contain actin binding domains. Mutations in ACTN4 can cause the kidney disease focal segmental glomerulosclerosis . Genes ACTN1 , ACTN2 , ACTN3 , ACTN4 See also actin External links MeshName Actinin Cytoskeletal Proteins Category Proteins protein stub es Actinina alfa ... more details
Stress fibers are high order structures in cells consisting of actin filaments aka microfilaments , crosslinking proteins proteins that bind two or more filaments together , and myosin II motors. Actin is a globular protein 43 kDa . It polymerizes, forms into an ordered filament structure which has two protofilaments wrapping around each other, to form a single actin filament also known as a microfilament . Microfilament is an old term that originated before protein composition of the filaments was understood. Actin filament is the typically accepted terminology in scientific circles now. The myosin motors in the stress fibers move, sliding actin filaments past one another, so the fiber can contract. The process of stress fiber dynamics is currently being rigorously studied and is not yet well understood. In order for contraction to generate forces the fibers must be anchored to something. Stress fibers can anchor to the cell membrane, and frequently the sites where this anchoring occurs are also connected to structures outside the cell the matrix or some other substrate . These connection sites are called focal adhesions. Many proteins are required for proper focal adhesion production and maintenance. Contraction against these fixed external substrates is what allows the force generated by myosin motors and filament growth and rearrangement to move and reshape the cell. Category Biology Category Cells External links http manual.blueprint.org Home stress fibers The Manual of Cellular and Molecular Function Stress fibers ... more details
The Spitzenk rper is a structure found in fungal hyphae which is the organizing center for hyphal growth and morphogenesis . It consists of many small vesicle biology vesicles and is present in growing hyphal tips, during spore germination and where branch formation occurs. Its position in the hyphal tip correlates with the direction of hyphal growth. The spitzenk rper is a part of the endomembrane system system in fungi. ref name Steinberg cite journal last Steinberg first G. year 2007 url http ec.asm.org cgi content full 6 3 351 title Hyphal growth a tale of motors, lipids, and the spitzenk rper journal Eukaryotic Cell volume 6 issue 3 pages 351 360 doi 10.1128 EC.00381 06 pmid 17259546 pmc 1828937 ref The vesicles are organized around a central area that contains a dense meshwork of microfilament s. Polysome s are often found closely to the posterior boundary of the Spitzenk rper core, microtubules extend into and often through the Spitzenk rper and Woronin body Woronin bodies are found in the apical region near the Spitzenk rper. ref cite doi 10.1128 EC.4.2.225 229.2005 ref References reflist category Cell biology category Fungal morphology and anatomy Cell biology stub fungus stub it Spitzenkorper pt Spitzenk rper ... more details
The three letter abbreviations three letter abbreviation ADF may refer to Computing and technology Advanced Format , a hard disk technology where sectors are over the 512 bytes limit Application Development Facility , a programming language Application Development Framework , a software framework in computer programming Oracle Application Development Framework Automatically Defined Functions, in genetic programming computer science Amiga Disk File Amsterdam Density Functional , a computer program to assist calculations in the field of chemistry Auto lead Data Format , an XML based standard for dealing in vehicles Automated Document Factory , a Gartner architecture for printing and mailing Automatic Document Feeder , in printers and scanners Music A Dozen Furies , the band who won the 2004 Battle for Ozzfest Asian Dub Foundation , a British band Organizations African Development Foundation , an Independent United States Government Agency Alliance Defense Fund , a US organization that engages in litigation on behalf of conservative Christian principles. Allied Democratic Forces , a Ugandan rebel group America s Development Foundation redlink refer Moscow Research Center for Human Rights r nDra ocht F in , a Neopagan druid organization Arab Democracy Foundation , an Arab civil society organization based in Qatar School debating in Australia Australian Debating Federation ADF Australian Debating Federation Australian Defence Force Azerbaijan Democratic Party ADF Other Actin depolymerizing factor s are a family of microfilament proteins African dwarf frog Aircraft Deicing fluid Deicing Fluid Albert Daly Field , a sports stadium in Williamsburg, Virginia Alternate day fasting, a diet that involves intermittent fasting on alternate days Alternative display facility , a type of financial exchange American Dance Festival , a modern dance summer event in the United States of America AnDan FOSSIL redlink Anders Danielson FOSSIL driver Andorran franc, ISO 4217 Code for a 1 1 p ... more details
Image MreB.png thumb Procaryotic MreB Protein Data Bank PDB code 1jce in cartoon representation. The fold of the protein is similar to its eukaryotic counterpart actin . MreB is a protein found in bacteria that has been identified as a homology biology homologue of actin , as indicated by similarities in tertiary structure and conservation of active site amino acid sequence peptide sequence . The conservation of protein structure suggests the common descent common ancestry of the cytoskeleton cytoskeletal elements formed by actin, found in eukaryote s, and MreB, found in prokaryote s. Indeed, recent studies have found that MreB proteins polymerization polymerize to form filaments that are similar to actin microfilament s. Function MreB controls the width of rod shaped bacteria , such as Escherichia coli . A mutant E. coli that creates defective MreB proteins will be spherical instead of rod like. Also, bacteria that are naturally spherical do not have the gene encoding MreB. Prokaryotes carrying the mreB gene can also be helix helical in shape. MreB forms a helical filament underneath the cytoplasmic membrane cell membrane and it has been shown to interact with several proteins that are proven to be involved in length growth for instance PBP2 . Therefore, it probably directs the synthesis of the insertion of new peptidoglycan building units into the existing peptidoglycan layer to allow length growth of the bacteria. Sources cite journal author Erickson H title Cytoskeleton. Evolution in bacteria journal Nature volume 413 issue 6851 pages 30 year 2001 pmid 11544510 url http www.nature.com nature journal v413 n6851 full 413030a0.html doi 10.1038 35092655 source of information added to this entry as of February 20, 2006 Cytoskeletal Proteins DEFAULTSORT Mreb Category Proteins bacteria stub protein stub es MreB ru MreB uk MreB ... more details
focal adhesion and microfilament protein VASP is a ligand for profilins journal EMBO J. volume 14 issue ... related protein that binds the focal adhesion and microfilament protein VASP vasodilator stimulated ... al. title The proline rich focal adhesion and microfilament protein VASP is a ligand for profilins ... expression of the proline rich focal adhesion and microfilament associated protein VASP. journal ... more details
functions in cells To form microfilament s, the most dynamic of the three subclasses of the cytoskeleton ... signal transduction. To allow cell motility see MicrofilamentMicrofilament based motility ... filament can be determined by decorating the microfilament with myosin S1 fragments, creating ... which remain bound in the microfilament . Straub suggested that the transformation of ATP bound ... more details
Image Pipe cleaner white.jpg thumb 350px A plain white pipe cleaner. A pipe cleaner is a type of brush originally intended for cleaning smoking pipe tobacco smoking pipe s. Besides cleaning pipes, they can be used for any application that calls for cleaning out small bores or tight places. Special pipe cleaners are manufactured specifically for cleaning out medical apparatus ref cite web url http www.clinipak.co.uk flexistem.aspx title medical pipe cleaners year 2009 ref and for engineering applications. ref cite web url http www.hewittandbooth.com title engineering year 2009 ref They are popular for catching drips, bundling things together, colour coding, and applying paints, oils, solvents, greases, and similar substances. Description Smoking pipe cleaners normally use some absorbent material, usually cotton or sometimes viscose . Bristles of stiffer material, normally monofilament nylon or polypropylene are sometimes added to better scrub out what is being cleaned. Microfilament polyester is used in some technical pipe cleaners because polyester wicks liquid away rather than absorbing it as cotton does. Some smoking pipe cleaners are made cone geometry conical or tapered so that one end is thick and one end thin. The thin end is for cleaning the small bore of the pipe stem and then the thick end for the bowl or the wider part of the stem. When cleaning a pipe, pipe cleaners are normally discarded after one or two uses. Children Many children enjoy bending pipe cleaners into various shapes. ref cite web url http www.marthastewart.com article pipe cleaner creatures title Pipe Cleaner Creatures year 2006 accessdate 2008 11 10 ref Craft pipe cleaners are usually made with polyester or nylon pile and are often longer and thicker than the smoking type, and available in many different colors. Craft pipe cleaners are not very useful for cleaning purposes, because the polyester does not absorb liquids, and the thicker versions may not even fit down the stem of a normal pi ... more details
protein Name Destrin actin binding protein caption Protein nuclear magnetic resonance spectroscopy Nuclear magnetic resonance determined configuration of the tertiary structure of Destrin. ref name pmid8674111 PDB 1AK6 cite journal author Hatanaka H, Ogura K, Moriyama K, Ichikawa S, Yahara I, Inagaki F title Tertiary structure of destrin and structural similarity between two actin regulating protein families journal Cell volume 85 issue 7 pages 1047 55 year 1996 month June pmid 8674111 doi 10.1016 S0092 8674 00 81305 7 url issn ref image Destrin.png width HGNCid 15750 Symbol DSTN AltSymbols ADF EntrezGene 11034 OMIM 609114 RefSeq NM 006870 UniProt P60981 PDB ECnumber Chromosome 20 Arm p Band 12.1 LocusSupplementaryData Destrin or DSTN also known as actin depolymerizing factor or ADF is a protein which in humans is encoded by the DSTN gene . ref name entrez cite web title Entrez Gene Destrin url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 11034 accessdate ref ref name pmid8399167 cite journal author Hawkins M, Pope B, Maciver SK, Weeds AG title Human actin depolymerizing factor mediates a pH sensitive destruction of actin filaments journal Biochemistry volume 32 issue 38 pages 9985 93 year 1993 month September pmid 8399167 doi 10.1021 bi00089a014 url issn ref ref name pmid11780052 cite journal author Deloukas P, Matthews LH, Ashurst J, et al. title The DNA sequence and comparative analysis of human chromosome 20 journal Nature volume 414 issue 6866 pages 865 71 year 2001 pmid 11780052 doi 10.1038 414865a url issn ref Destrin is a component protein in microfilament s. The product of this gene belongs to the actin binding proteins ADF Actin Depolymerizing Factor cofilin family. This family of proteins is responsible for enhancing the turnover rate of actin in vivo. This gene encodes the actin depolymerizing protein that severs actin filaments F actin and binds to actin monomers G actin . Two transcript variants encoding distinct isofo ... more details
Image Preprophaseband.png thumb The preprophase band predicts the cell division plane 1 Preprophase band formation during preprophase . 2 Metaphase spindle orients with the equator along the plane marked by preprophase band. 3 Phragmoplast and cell plate form along the plane marked by preprophase band. 4 The new cell wall of the daughter cells connects with the parent cell wall along the line of the former preprophase band location. The preprophase band is a microtubule array found in plant cell s that are about to undergo cell division and enter the preprophase stage of the plant cell cycle . Besides the phragmosome , it is the first microscopically visible sign that a plant cell is about to enter mitosis . The preprophase band was first observed and described by Jeremy Pickett Heaps and Donald Northcote at Cambridge University in 1966 . ref name Pickett Heaps cite journal author Pickett Heaps JD, Northcote DH title Organization of microtubules and endoplasmic reticulum during mitosis and cytokinesis in wheat meristems journal Journal of Cell Science year 1966 volume 1 pages 109 120 pmid 5929804 issue 1 ref Just before mitosis starts, the preprophase band forms as a dense band of microtubules around the phragmosome and the future division plane just below the plasma membrane . It encircles the Cell nucleus nucleus at the equatorial plane of the future mitotic spindle when dividing cells enter the G2 phase of the cell cycle after DNA replication is complete. The preprophase band consists mainly of microtubules and microfilament s actin and is generally 2 3 m wide. When stained with fluorescent markers, it can be seen as two bright spots close to the cell wall on either side of the nucleus. Plant cells lack centrosome s as microtubule organizing center s. Instead, the microtubules of the mitotic spindle aggregate on the nuclear surface and are reoriented to form the spindle at the end of prophase. The preprophase band also functions in properly orienting the mi ... more details
Pfam box Symbol Kelch 1 Name Kelch motif image 1gof front.GIF width caption Pfam PF01344 InterPro IPR006652 SMART Prosite SCOP 1gof TCDB OPM family OPM protein PDB PDB3 1u6d X 459 504 PDB3 1zgk A 459 504 PDB3 1goh 311 357 PDB3 1gof 311 357 PDB3 1gog 311 357 Kelch proteins and Kelch like protein s are a widespread group of proteins that contain multiple Kelch motif s. The kelch domain generally occurs as a set of five to seven kelch repeats that form a propeller tertiary structure. Kelch repeat propellers are generally involved in protein protein interactions, though the large diversity of domain architectures and limited sequence identity between kelch motifs make characterisation of the kelch superfamily difficult. Structure The N terminal end N terminus of several Kelch proteins contain other protein domains, including Discoidin, F box, and Broad complex, Tramtrack, Bric a Brac Poxvirus and Zincfinger BTB POZ domains. Kelch proteins may also have only a propeller architecture only. The BTB domain of kelch proteins if present allows the formation of homo or heterodimers that mediate protein protein interaction s. The C terminal end C terminus of Kelch proteins contains kelch repeats. Each kelch repeat is a sequence of 44 55 amino acid s in length, usually occurring in clusters of 4 7 repeats. Each kelch repeat forms a blade of the propeller fold, consisting of a four stranded antiparallel Beta sheet sheet secondary structure , arranged radially around a central axis, packed onto its adjoining repeats via hydrophobic contacts. Kelch repeat propellers undergo a variety of binding interactions with other proteins, notably the Microfilament actin filaments of a cell. Function The function of Kelch proteins is unknown. However they are commonly seen to associate with actin tails. Organisms The first Kelch protein from which this family derives its name was isolated from Drosophila . It has also been isolated in many other animals, bacteria, fungi, and even v ... more details
TOCright Intermediate filaments IFs are a family of related proteins that share common structural and sequence features. Intermediate filaments have an average diameter of 10 nanometer s, which is between that of actin microfilament s and microtubule s, although they were initially designated intermediate because their average diameter is between those of narrower microfilament s actin and wider myosin filaments. ref cite pmid 5664223 cite pmid 17551517 ref Most types of intermediate filaments are cytoplasm ic, but one type, the Type V Nuclear Lamins lamins , are nuclear. Structure File Intermediate filament.svg thumb left 300px Structure of intermediate filament The domain structure of IF molecules is conserved. Each protein has a non alpha helical globular domain at the N and C termini, which surrounds the alpha helical rod domain. The basic building block for IFs is a parallel and in register protein dimer dimer . The dimer is formed through the interaction of the rod domain to form a coiled coil . ref name Qin2009 cite pmid 19806221 ref Cytoplasmic IF assemble into non polar unit length filaments ULF , which then assemble into longer structures. Part of the assembly process includes a compaction step, in which ULF tighten and assume a smaller diameter. The reasons for this compaction are not well understood, and IF are routinely observed to have diameters ranging between 6 and 12 nm. The anti parallel orientation of tetramers means that, unlike microtubules and microfilaments, which have a plus end and a minus end, IFs lack polarity. Also, as opposed to actin or tubulin , intermediate filaments do not contain a binding site for a nucleoside triphosphate . Cytoplasmic IF do not undergo treadmilling like microtubules and actin fibers, but they are dynamic. For a review see http jcs.biologists.org cgi content full 117 2 133 . Biomechanical properties IFs are rather deformable proteins that can be stretched several times their initial length. ref cite pmid 1755 ... more details
Unreferenced date November 2007 misleading fancruft date January 2011 Monomolecular wire or Monofilament is a fictional wire, often used as a weapon, consisting of single strand of strongly bonded molecules, like carbon nanotube s. It has applications in cutting objects and severing adjacent molecules. A similar or identical concept may be called a microfilament wire or, as a weapon, a microfilament whip . Scientific basis The science behind this fictional weapon is fairly simple working from the principle that the thinner the cutting edge the more keen the weapon, but there is no substance that is currently known that will provide such a strong bonding for the creation of monomolecular materials. Furthermore most representations of monomolecular wire fall short in several places and many uses of them are even more fictitious. Some characters are frequently shown as being able to use this wire as garottes but without inflicting any harm on their own hands. Many characters can also throw and control these wires almost telekinetically how is almost never explained . Wire such as this would in reality not have enough weight to fly properly or place much force behind it, unless it had some type of weight on its tip to maintain the wire s rigidity while in motion. Sometimes, they also seem to only cut when the user wants them to, being able to both bind a person without harming him or her and slice hordes of armored enemies with ease. Monocrystalline Metals off topic date January 2011 While a monocrystalline wire is at present a theoretical construct, there are applications for monocrystalline cast metal ingots. These are produced by slowly dropping carbon steel into a steeping bath of very cold water. The resulting steel bars are extremely strong, and chemically uniform monocrystalline, with a regular crystal structure. These have applications in aerospace, typically as the base material for gas turbine hot section blades in jet engines and power station turbines , and ... more details
microfilament s through interaction with actin . Microtubule motors such as dynein and kinesin move ... in cytoplasmic streaming , wherein movement along microfilament networks in the cell allows organelle ... more details
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