myofibril


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Related to myofibril: myofilament, sarcoplasmic reticulum

myofibril

 [mi″o-fi´bril]
one of the slender threads of a muscle fiber, composed of numerous myofilaments; called also muscle fibril. adj., adj myofi´brillar.
Bundles of myofibrils in a muscle. From Damjanov, 2000.

my·o·fi·bril

(mī'ō-fī'bril),
One of the fine longitudinal fibrils occurring in a skeletal or cardiac muscle fiber comprising many regularly overlapped ultramicroscopic thick and thin myofilaments.
[myo- + Mod. L. fibrilla, fibril]

myofibril

/myo·fi·bril/ (-fi´bril) muscle fibril; one of the slender threads of a muscle fiber, composed of numerous myofilaments. myofi´brillar

myofibril

(mī′ə-fī′brəl, -fĭb′rəl)
n.
Any of the threadlike fibrils that make up the contractile part of a striated muscle fiber and are made up chiefly of actin and myosin filaments.

myofibril

[-fī′bril]
Etymology: Gk, mys + L, fibrilla, small fiber
a slender striated strand within skeletal and cardiac muscle fibers and composed of bundles of myofilaments. Myofibrils occur in groups of branching threads running parallel to the cellular long axis of the fiber.
enlarge picture
Molecular structure of a myofibril

myofibril

A bundle of contractile fibres within muscle cells.

my·o·fi·bril

(mī'ō-fī'bril)
One of the fine longitudinal fibrils occurring in a skeletal or cardiac muscle fiber and consisting of many regularly overlapped ultramicroscopic thick and thin myofilaments.
[myo- + Mod. L. fibrilla, fibril]

myofibril

a microscopic contractile filament of STRIATED MUSCLE, made up of a series of SARCOMERES. The myofibril is made up of numerous longitudinal filaments of two forms, thick (MYOSIN) and thin (ACTIN). See MUSCLE, I-BAND. Relatively little is known of the contraction of smooth muscle, where contractile elements’ are thought to contain both actin and myosin.

myofibril

a longitudinal, multicellular fibre, characteristic of striated (i.e. skeletal and cardiac) muscle, formed of actin and myosin filaments; Ca2+ interaction between actin/myosin causes increasing linear overlap of these protein molecules, with resultant muscle tension/contraction

myofibril

a muscle fibril, one of the slender threads of a muscle fiber, composed of numerous myofilaments.
References in periodicals archive ?
2] was likely related to the disorganization of myofibrils and increase of gaping in fillets, which may lead to the change in color and obvious decrease in chewiness, springiness, and cohesiveness of the flesh during storage (Table 2).
The low molecular weight GTPase Rho regulates myofibril formation and organization in neonatal rat ventricular myocytes.
Both denaturation and melting of the endomysium, and denaturing of myofibrils resulted in fiber swelling.
6D and G) revealed a large number of cells in different stages of necrosis, showing vacuolization of muscle cells and hypercontraction of myofibrils.
When muscle foods are heated, the protein in the myofibrils and the connective tissue undergo changes in configuration, leading to structural changes and contraction of the muscle tissue.
The main role of different isoenzymes of CK in cardiac muscle is to form a 'creatine shuttle', which means that the ATP synthesized in the mitochondrial matrix is used by MtCK for the synthesis of PCr in the mitochondrial intermembrane space to form a new energy-rich phosphoryl product; PCr then enters the cytoplasm and is transported to the myofibril by a facilitated diffusion mechanism.
Additionally, myogenin, a gene involved in mature myofibril differentiation, exhibits elevated expression in the paretic leg.
In addition, a second oral presentation entitled, "Cardiac Myosin Activator, CK-1316719, Increases Myofibril ATPase Activity and Myocyte Contractility in a Rat Model of Heart Failure," provided data further validating the mechanism of another of Cytokinetics' cardiac myosin activators.
This extremely large protein (~ 1 MgDa) has a modular repeated structure, and localizes over the I-Z-I region of the myofibril in insect flight muscles.
Ternary troponin complex, consisting of subunits I, T, and C, is part of the myofibril contractile apparatus in striated muscle cells.
The proteins of the fish can be divided into three classes: myofibril proteins (or structure proteins) (60 to 65%), sarcoplasmic proteins (20 to 30%), extracellular or support proteins (5 to 8%) [5].
Using light microscopy, and image processing and analysis, they found the distance between myofibrils decreased gradually with time, both in longitudinal- and cross-sections of tissue, due to myofibril detachment from the myocommata.