actin


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actin

 [ak´tin]
a muscle protein localized in the I band of myofibrils; acting along with myosin particles, it is responsible for the contraction and relaxation of muscle fibers.

ac·tin

(ak'tin),
One of the protein components into which actomyosin can be split; it can exist in a fibrous form (F-actin) or a globular form (G-actin).

actin

/ac·tin/ (ak´tin) a muscle protein localized in the I band of the myofibrils; acting along with myosin, it is responsible for contraction and relaxation of muscle. It occurs in globular (G-actin) and fibrous (F-actin) forms.

actin

(ăk′tĭn)
n.
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.

actin

a protein forming the thin filaments in muscle fibers that are pulled on by myosin cross-bridges to cause a muscle contraction. Some bacteria forms actin tails to use for motility. See also myosin.

Actin

One of two major muscle proteins—the other is myosin—which is an ATPase that binds to adenine nucleotides. In concert with myosin, actin is a filamentous protein responsible for muscle contraction, and has an active mechanicochemical role in cell function; it is divided into a 46-kD monomeric form, G-actin and a mature contractile form, F-actin, formed from G-actin polymers, capable of functioning in absence of myosin.

ac·tin

(ak'tin)
One of the protein components into which actomyosin can be split; it can exist in a fibrous form (F-actin) or a globular form (G-actin).

actin

A contractile protein in muscle, found in the thin filaments, to which the myosin cross-bridges bind. Actin filaments are also abundant inside all nucleated cells where they form the cytoskeleton, determining cell shape and, in the case of amoebic cells, cell movement. An actin contractile ring forms around the equator of a dividing cell at the end of MITOSIS and tightens so as to pinch the two daughter cells apart.

actin

a contractile protein found in the muscles of all animals from protozoa to vertebrates and in the MICROFILAMENTS of all cells. The energy for contraction is derived from ATP; See MYOSIN.
Figure 1: The autonomic nervous system. Actions on secretory functions (heart diagrams indicate release into the circulation). Sympathetic actions on the left and parasympathetic actions on the right. Solid arrows: stimulation (contraction or secretion); broken arrows: inhibition.

actin

globular protein molecule which readily links with others (with consumption of ATP) to form long, double-helical strands. Such actin filaments are found in a wide variety of animal and plant cells, as well as forming the structural core and main (but not only) component of the thin filaments in the myofibrils of all animal muscles. Actin is thus a protein of great evolutionary antiquity and vertebrate striated muscles are unusual only in having a very high content of it (80% of total protein), and in its highly ordered locations within the cells, where thin filaments alternate with thick filaments containing actin's partner protein myosin, to form the cross-striated pattern. See also muscle, muscle fibres; Figure 1.

actin (akˑ·tin),

n one of a pair of myofilaments involved in muscle contractions. See also myosin.

actin

a muscle protein localized in the I band of myofibrils; acting along with myosin particles, it is responsible for the contraction and relaxation of muscle.

actin F
assembly of actin G monomers into filaments.
actin filaments
smallest filamentous proteins involved in a static role in cell structure and a dynamic role in cell movement.
actin G
monomeric globular protein which assembles into actin filaments.
References in periodicals archive ?
Diminished adhesion and spreading of cells is indicated by diffuse presence of actin and absence of focal contacts.
The concentration of gelsolin seems to be rate limiting in the actin removal system and depends on the rates of formation, dissociation, and clearance of the actin-gelsolin complex.
The levels of actin were not affected by treatment with wortmannin (Figure 5).
Inhibition of Rho, Rac, and Cdc42 by compactin and Clostridium difficile ToxB, as well as dominant negative alleles, had no effect on pedestal formation by EPEC, which suggests that this pathogen uses a nontraditional mechanism to rearrange actin.
Scientists already knew that actin tails propel the intestinal disease bacteria Shigella and Listeria.
Actin provides many optimized control strategies that can be cascaded to build control systems quickly and easily.
We developed Actin for NASA robots," said Neil Tardella, COO at Energid, "for the harsh environment of space.
CEA licensed Energid's Actin software to be the brains of the AIA robot.
Fibers composed of a protein called actin are responsible for human cells' ability to tell right from left, researchers report in the April Nature Cell Biology.
The predicted HvRGAl protein has the typical NBS-LRR R-gene structure and the HvAdf3 gene is predicted to encode an actin depolymerization factor.
ACTIN accused the breeders of "selfishly bleating about the animals that they sold" and said they were "concerned only for themselves".
ACTIN said when they first visited the premises there were even more animals there than they eventually rescued.