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Related to actin: beta actin


A protein that forms the microfilaments of the eukaryotic cytoskeleton and plays an important role in cell movement, shape, and internal organization. In muscle cells, it functions with myosin to produce contraction.

[Latin āctus, motion; see act + -in.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biochemistry) a protein that participates in many kinds of cell movement, including muscle contraction, during which it interacts with filaments of a second protein, myosin
[C20: from act + -in]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈæk tən)

a protein that functions in muscular contraction by combining with myosin. Compare actomyosin.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.actin - one of the proteins into which actomyosin can be split; can exist in either a globular or a fibrous form
actomyosin - a protein complex in muscle fibers; composed of myosin and actin; shortens when stimulated and causes muscle contractions
simple protein - a protein that yields only amino acids when hydrolyzed
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in classic literature ?
They'll get a good bit o' actin' out of it an' there's nothin' children likes as much as play actin'.
She was quite right, the comfortable wonderful mother creature--and she had never been more so than when she said their "play actin'" would be their joy.
See 'em now, actin' to be genewine moss-backs - every hair a rope- yarn an' blood Stockholm tar." He spoke down the cabin stairs.
Actin is the most abundant protein in eukaryotic cells.
Actin has proven deployments in industrial, commercial, collaborative, and consumer robotic systems such as mobile robots, robots mounted on rails, underwater robots and bin picking.
Actin is especially well suited to solving complex motion control problems, said Neil Tardella, Energid CEO and co-founder.
Actin is important to a number of vital cell functions, including maintenance of the cytoskeleton, which defines cell shape and structure.
Actin control toolkit allows development team to focus on robot hardware and surgeon command center Leveraging Energid's Actin software to tackle the complex motion-control problem freed the SSI team to focus on creating robot hardware and a surgeon command center to address core clinical use cases.
The latter is composed of antiparallel homodimers that crosslink the thin actin filaments of neighboring sarcomeres (Yu et al., 2003).
To better understand the process of the simultaneous formation of the first two polar bodies in an androgenetic clam, the meiotic process was observed by visualizing cytoskeletal elements, such as microtubules and centrosomes, and distribution of actin. In the present study, the detailed process of cytokinesis during the formation of the first two polar bodies in Corbicula fluminea was demonstrated by confocal microscopy.
The functional significance of a-smooth muscle actin staining abnormalities in gastrointestinal disease is still unclear.