actin, a protein abundantly present in many cells, especially muscle cells, that significantly contributes to the cell's structure and motility. Actin can very quickly assemble into long polymer rods called microfilaments. These microfilaments have a variety of roles—they form part of the cell's cytoskeleton, they interact with myosin myosin , one of the two major protein constituents responsible for contraction of muscle. In muscle cells myosin is arranged in long filaments called thick filaments that lie parallel to the microfilaments of actin.
..... Click the link for more information. to permit movement of the cell, and they pinch the cell into two during cell division. In muscle contraction, filaments of actin and myosin alternately unlink and chemically link in a sliding action. The energy for this reaction is supplied by adenosine triphosphate adenosine triphosphate (ATP) , organic compound composed of adenine, the sugar ribose, and three phosphate groups. ATP serves as the major energy source within the cell to drive a number of biological processes such as photosynthesis, muscle contraction, and the
..... Click the link for more information. .

actin

One of two proteins responsible for contraction of muscle cells and the motility of other cells. It occurs as a monomer, G-actin, a globular protein, and in living cells as a polymer, F-actin, which resembles two strings of beads twisted around each other into thin filaments. The filaments occur in regular structures, alternated and interwoven with thick filaments that contain myosin, the other major muscle protein. The thick and thin filaments slide past each other, under the control of calcium ions, resulting in contraction (shortening) and relaxation (lengthening) of the muscle cells.

actin [′ak·tən]

(biochemistry)

A muscle protein that is the chief constituent of the Z-band myofilaments of each sarcomere.

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No references found	Fyodor III Fyr-BÜl Fest Fyt, Jan g G center g constant G display G drift g factor g file g force G indicator G line g load g parameter G parity G protein G scan G scope g service G space G star G string g suit G value G-actin g-bell g-cal g-cm G-Code g-completeness G-cramp g-incompleteness G-list G-man G-protein-linked receptor G-string G-suit G. standards G.711 G.721 G.722 G.723 G.723.1 G.726 G.727 G.728 G.729 G.729.A G.bond G.I. Bill WWII U.S.	G-24 G-3 G-3 G-3 G-3 G-30 G-30 G-33 G-4 G-4 G-5 G-5 G-5 G-5 G-6 G-6 G-7 G-7 G-7 G-7 G-77 G-77 G-8 G-8 G-8 G-8 G-8 Finance Ministers G-8 Summit G-9 G-A G-actin G-ADCAP G-agent G-ALWT G-BA G-banding G-banding stain g-bell G-BMC G-BOAA G-Box Regulatory Element G-BW G-byte G-byte G-byte G-C g-cal G-CAS G-CASE G-CCS G-CDR G-cells G-cGH G-clamp G-clamp g-cm G-code g-completeness

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actin (redirected from G-actin)

actin

actin
(redirected from G-actin)