actin, or F actin. Each microfilament is made up of two helical helix , interlaced strands of subunits ... ref Microfilament associated proteins In non muscle cells, actin filaments are formed proximal to membrane ... MeshName Microfilament proteins eMedicineDictionary Microfilament DorlandsDict five 000066329 Microfilament ... ca Microfilament cs Mikrofilamentum cy Microffilament de Mikrofilamente et Aktiinifilamendid el ... it Microfilamento jv Mikrofilam n lt Mikrofilamentas ja oc Microfilament pl Mikrofilament ... more details
Wikify date January 2012 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 Cells ... more details
Actinin is a microfilament protein. ACTN1 Actinin is necessary for the attachment of actin filaments to the Sarcomere Z line s in skeletal muscle cells, and to the Smooth muscle tissue 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 cs Aktinin es Actinina alfa sk Aktin n ... more details
Actin depolymerizing factors are a family of microfilament protein s. 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
Taxobox name Arthracanthida domain Eukaryote Eukaryota unranked phylum Rhizaria phylum Radiolarian Radiolaria classis Acantharea subclassis Arthracanthida subclassis authority Schewiakoff, 1926 ref cite web author WoRMS year 2010 title Arthracanthida publisher World Register of Marine Species url http www.marinespecies.org aphia.php?p taxdetails&id 367301 accessdate July 17, 2011 ref synonyms Acanthometrida Arthracanthida , a sub class of Acantharea , is a group of marine protozoan s. They consist mainly of a gelatinous sheath filled with cytoplasm and a skeleton of up to 20 radially placed spicule s made of celestite . While mostly found in the upper areas of the ocean, they are able to move vertically by using microfilament s attached to the spicules to expand and contract the sheath. They are plentiful in the Gulf Stream during the summer months, but little is known about their overall distribution. References reflist L. H. Hyman, The Invertebrates, vol. 1, McGraw Hill, 1940 T. Cavalier Smith, Kingdom Protozoa and its 18 phyla, Microbiol. Rev., 57 4 953 994, 1993 K. Hausmann and N. Hulsmann, Protozoology, Georg Thieme Verlag, New York, 1996 Category Radiolarians ... 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 The cytoplasm of the extreme apex is occupied almost exclusively by secretory vesicles and microvesicles. In the higher fungi Asco and Basidiomycota , the former are arranged as a spherical shell around the latter, and the entire formation is called the Spitzenkorper or apical body . The Spitzenkorper may be seen in growing hyphae even with the light microscope. Hyphae of the Oomycota and some lower Eumycota notably the Zygomycota do not contain a recognizable Spitzenkorper, and the vesicles are instead distributed more loosely in the apical dome. ref John Webster and R. W. S. Weber. 2007 . Introduction to Fungi.United States of America by Cambridge University Press, New York.PP 841. ref References reflist DEFAULTSORT Spitzenkorper Category Cell biology Category Fungal morphology and anatomy Cell biology stub fungus stub gl Spitzenk rper it Spitzenkorper pt Spitzenk rper ... more details
The LINC complex Linker of Nucleoskeleton and Cytoskeleton is a protein complex associated with both inner and outer membranes of the cell nucleus nucleus and actin in the microfilament cytoskeleton. The LINC complex is involved in the anchoring of both nuclear membranes and nuclear lamina to the actin cytoskeleton via transmembrane proteins. The LINC complex consists of SUN2 and Samp1 of the inner nuclear membrane proteins inner nuclear membrane and nesprin 2G of the outer nuclear membrane. SUN2 anchors to the nuclear lamina aided by Samp1, whilst nesprin 2G associates with the actin microfilaments. Alternatively Generally In the outer nuclear membrane KASH domain proteins connect the nucleus to the actin cytoskeleton, at the inner nuclear membrane SUN domain proteins connect KASH domain proteins to typeA lamins. Therefore KASH SUN protein complex is another name for the LINC complex. ref J.Borrego Pinto et al. 2012 Samp1 is a component of TAN lines and is required for nuclear movement Journal of Cell Science 125, 1 7 doi 10.1242 jcs.087049 ref ref V.C.Padmakumar et al. 2005 The inner nuclear membrane protein Sun1 mediates the anchorage of Nesprin 2 to the nuclear envelope Journal of Cell Science 118, 3419 3430 doi 10.1242 jcs.02741 ref Function The function of the LINC complex appears to be in nuclear relocation movement. On the dorsal surface of the nucleus the LINC complexes form linnear arrays corresponding to the localization of F actin. The structures are called TAN lines Transmembrane actin associated nuclear are thought to transmitt the force from retrograde flow of actin to the nucleus.. ref J.Borrego Pinto et al. 2012 Samp1 is a component of TAN lines and is required for nuclear movement Journal of Cell Science 125, 1 7 doi 10.1242 jcs.087049 ref Reflist Category Protein complexes ... more details
ref Actin is found in both smooth and rough endoplasmic reticulums. Functions Actin forms microfilament ... . In turn, this gives actin major functions in cells To form microfilament s to give mechanical ... To allow cell motility in cells which undergo amoeboid motion using pseudopods see MicrofilamentMicrofilament based motility by actoclampin molecular motors actoclampin molecular motors and phagocytosis ... for import. Directionality The polarity of an actin filament can be determined by decorating the microfilament ... diphosphate ADP and inorganic phosphate which remain bound in the microfilament . Straub suggested ... 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 . Use and variants in fiction An early example of a substance similar to monomolecular wire is shigawire , as described in Frank Herbert s Dune novels. First making its appearance in Dune novel Dune 1965 , shigawire is a metallic extrusion produced naturally from a ground vine found on the planets Salusa Secundus and III Delta Kaising . It varies in diameter from approximately 1.5 cm down to monomolecular micronic diameters, and is notable for its incredible tensile and mechanical strength. Shigawire is able to cut through almost any material cleanly, possessing edges that are incredibly sharp. It is a weapon of choice for assassins, able to both garrote and decapitate in one swift motion. It finds widespread use in the Dune universe, not only as a weapon system, but as an information recording material shigawire is able to accept magnetic fields imprinted along its length in the style of magnetic tape, giving rise to the wire projector, which displays holographic images and films whose data is imprinted on a shigawire reel. Minimic film is monomolecular shigawire which has been used to record data great care is needed while handling this material, as carelessness will result in the film cutting through its canister, playback recorder machine, and the hapless user if the film is moving at a velocity greater than 1 metre per second. Shigawire also has application in art, including that of mobile sculpture. A notable piece of the latter, called Being Unknown , was taken by Honored Matres during their invasion of the Old Empire, and retained at the captured palace ... more details
The three letter abbreviations three letter abbreviation ADF may refer to Computing and related technology Advanced Format , a hard disk technology where sectors are over the 512 bytes limit Amiga Disk File Amsterdam Density Functional , a computer program for performing density functional theory electronic structure calculations AnDan FOSSIL, a FOSSIL driver by AnDan Software Application Development Facility , a programming language Application Development Framework , a software framework in computer programming Oracle Application Development Framework 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 Automatically defined functions, in genetic programming computer science 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, refer to 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 Australian Drug Foundation Azerbaijan Democratic Firgue Other Actin depolymerizing factor s are a family of microfilament proteins African dwarf frog Aircraft 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 Andor ... 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 citation needed date December 2011 . 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 has long been thought to form a helical filament underneath the cytoplasmic membrane, however, this model has been brought into question by three recent publications showing that filaments cannot be seen by electron cryotomography and that GFP MreB can be seen as patches moving around the cell circumference. 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 and 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 Februa ... more details
Image Pipe cleaner white.jpg thumb 350px A plain white pipe cleaner. A pipe cleaner or chenille stem is a type of brush originally intended for cleaning dottle from 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 Clarify date April 2011 , 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 ... 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 mit ... more details
and microfilament protein VASP is a ligand for profilins journal EMBO J. volume 14 issue 8 pages ..., and characterization of a zyxin related protein that binds the focal adhesion and microfilament ... Reinhard M, Giehl K, Abel K, et al. title The proline rich focal adhesion and microfilament protein ..., structural analysis and functional expression of the proline rich focal adhesion and microfilament ... 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
protein Name CTNNA1 catenin cadherin associated protein , alpha 1, 102kDa caption image width HGNCid 2509 Symbol CTNNA1 AltSymbols EntrezGene 1495 OMIM 116805 RefSeq NM 001903 UniProt P35221 PDB ECnumber Chromosome 5 Arm q Band 31.2 LocusSupplementaryData protein Name catenin cadherin associated protein , alpha 2 caption image width HGNCid 2510 Symbol CTNNA2 AltSymbols EntrezGene 1496 OMIM 114025 RefSeq NM 004389 UniProt P26232 PDB ECnumber Chromosome 2 Arm p Band 12 LocusSupplementaryData p11.1 protein Name catenin cadherin associated protein , alpha 3 caption image width HGNCid 2511 Symbol CTNNA3 AltSymbols EntrezGene 29119 OMIM 607667 RefSeq NM 013266 UniProt Q9UI47 PDB ECnumber Chromosome 10 Arm q Band 21 LocusSupplementaryData Alpha catenin was suggested to function as a linking protein between cadherin s and Microfilament actin containing filaments of the cytoskeleton . ref cite book author Cooper, Geoffrey M. title The Cell A Molecular Approach publisher Sinauer Associates edition 2nd year 2000 isbn 0 87893 219 4 chapterurl http www.ncbi.nlm.nih.gov books NBK9908 figure A1784 chapter Figure 11.14 Model of attachment of actin filaments to catenin cadherin complexes url http www.ncbi.nlm.nih.gov books n cooper TOC ref It has been reported that the actin binding proteins vinculin ref cite journal author Watabe Uchida M, Uchida N, Imamura Y, et al. title alpha Catenin vinculin interaction functions to organize the apical junctional complex in epithelial cells journal J. Cell Biol. volume 142 issue 3 pages 847 57 year 1998 month August pmid 9700171 pmc 2148175 url http www.jcb.org cgi pmidlookup?view long&pmid 9700171 doi 10.1083 jcb.142.3.847 ref and alpha actinin ref cite journal author Knudsen KA, Soler AP, Johnson KR, Wheelock MJ title Interaction of alpha actinin with the cadherin catenin cell cell adhesion complex via alpha catenin journal J. Cell Biol. volume 130 issue 1 pages 67 77 year 1995 month July pmid 7790378 pmc 2120515 url http www.jcb.org cgi pmid ... more details
Orphan date April 2012 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, bact ... more details
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