myofibrils

..microtubules associate transiently with sarcomeric myosin and later with A-band titin when non-striated myofibrils differentiate into mature sarcomeres...

In the heart, the energy supplied by mitochondria to myofibrils is continuously and finely tuned to the contraction requirement over a wide range of cardiac loads...

..The dual interactions of MURF-1 with titin and GMEB-1 may link myofibril signaling pathways (perhaps including titin's kinase domain) with muscle gene expression...

..Together, these data indicate that SmyD1a and SmyD1b are histone methyltransferases and play a critical role in myofibril organization during myofiber maturation...

..This review focuses on the clinical and myopathological aspects of genetically defined MFMs, and shall provide a diagnostic guide for this numerically significant group of protein aggregate myopathies...

..These data raise the possibility that MURF-1 may coordinately regulate the energy metabolism of mitochondrial and cytoplasmic compartments...

The transverse stiffness of single myofibrils of skeletal and cardiac muscles was examined by atomic force microscopy...

..The effects of unc-45b knockdown on other sarcomeric structures and the phenotype of Unc-45b overexpression, however, are poorly understood in vertebrates...

..Striated staining of minK was observed in non-washed, membrane-intact cardiac myofibrils, but not in well-washed, membrane-removed cardiac myofibrils, suggesting that minK localizes on T-tubular ..

..These results show that integration of the M-band region of titin is required for myosin filament assembly, M-band formation and maturation of the Z-disk...

..determine whether PKG can phosphorylate titin and affect titin-based stiffness in skinned myofibers and isolated myofibrils. PKG in the presence of 8-pCPT-cGMP (cGMP) phosphorylated the 2 main cardiac titin isoforms, N2BA and N2B, in ..

..antibodies (mAbs) against a 165-kd fraction, we also obtained mAbs that bound to the M line of isolated myofibrils as detected by indirect immunofluorescence, but recognized a protein band of 185 kd in immunoblotting ..

..To probe the interaction in a more physiological environment, nonactivated cardiac myofibrils were stretched quickly, and force was measured during the subsequent hold period...

..The mechanisms that mediate the structural organization of the sarcoplasmic reticulum with respect to the myofibrils are, however, not known. We report here that ank1...

..Titin kinase phosphorylates the muscle protein telethonin in early differentiating myocytes, indicating that this kinase may act in myofibrillogenesis...

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..These data suggest that physical constrainment of muscle cells by extracellular matrix may be an important regulator of myofibrillar organization...

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..is dependent upon the proper alignment and coordinated activities of several cytoskeletal networks including myofibrils, microtubules, and intermediate filaments...

..The association of these damages accelerates the progression of diastolic heart failure progression in diabetic-banded animals...

..techniques that analyse the chemical and mechanical kinetics of small components of a muscle fibre, subcellular myofibrils isolated from skeletal and cardiac muscle...

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De novo assembly of myofibrils was investigated in explants of precardiac mesoderm from quail embryos to address a controversy about different models of myofibrillogenesis...

..However, in the majority of the myofibrillar myopathy patients the disease gene awaits discovery...

We review some of the problems in determining how myofibrils may be assembled and just as importantly how this contractile structure may be renewed by sarcomeric proteins moving between the sarcomere and the cytoplasm...

..In the presence of calcium, myofibrillar ATPase is activated and myofibrils either shorten with no external load (native myofibrils) or contract isometrically (cross-linked myofibrils)...

The high stiffness of relaxed cardiac myofibrils is explainable mainly by the expression of a short-length titin (connectin), the giant elastic protein of the vertebrate myofibrillar cytoskeleton...

..In summary, our data indicates that zebrafish are a valuable in vivo model for studying both myofibrillogenesis and sarcomere-based cardiac diseases...

..of cell shape and the composition and aggregation of contractile proteins into filaments, the sarcomere, and myofibrils. We examine how mechanical activity regulates the turnover and exchange of contraction proteins...

..We propose that the M-band is in fact a dynamic structure that monitors the stress appearing in the thick filament lattice during contraction and quickly reorganizes to meet new physiological requirements...

..C2-dihydroceramide enhanced apoptosis of cardiomyocytes by 50%, accompanied by detrimental effects on the myofibrils. The palmitic acid-induced effects were impaired by fumonisin B1, an inhibitor of ceramide synthase...

..This review summarizes current knowledge of this rapidly developing area with focus on how the heart adjusts physiological remodeling process to meet with mechanical demands and how this process fails in cardiac pathologies...

..5. Confocal microscopy of hearts of E8-8.5 Tmod1 null embryos revealed structures resembling nascent myofibrils with continuous F-actin staining and periodic dots of alpha-actinin, indicating that I-Z-I complexes assembled ..

..The functional importance of nebulin in skeletal muscle function was revealed by isometric contractility assays, which demonstrated a dramatic reduction in force production in nebulin-deficient skeletal muscle...

Tropomodulin (Tmod)1 caps the pointed ends of actin filaments in sarcomeres of striated muscle myofibrils and in the erythrocyte membrane skeleton...

..Both myosin and troponin isoforms contribute to the differences in the resistance to fatigue of muscle fibers...

..independent morpholino antisense oligonucleotides resulted in diminished numbers and marked disarray of skeletal myofibrils, impaired lateral alignment of adjacent myofibrils, disorganization of the sarcoplasmic reticulum, somite ..

..Further advances in defining the molecular causes of MFM will probably come from linkage studies of informative kinships or from systematic search for mutations in proteins participating in the intricate network supporting the Z-disk...

..model of myofibrillogenesis, based on observations in cultured avian muscle cells, proposes that mature myofibrils are preceded by two intermediary structures: premyofibrils and nascent myofibrils...

..Our data suggest Drosophila is a valuable system for identifying and modeling mutations analogous to those associated with specific human muscle disorders...

How proteins assemble into sarcomeric arrays to form myofibrils is controversial...

..The models hypothesize: (a) stress fiber-like structures as templates for the assembly of myofibrils, (b) assembly in which the actin filaments and Z-bands form subunits independently from A-band subunits, with ..

..proteins, we purified a combination of two uncommonly large proteins, designated as titin, from chicken breast myofibrils. Chemical and immunological studies indicated that titin is distinct from myosin, actin, and filamin...

..in myocardial ischemia reperfusion, calpain inhibitors decreased the level of cTnT-ND in Triton-extracted myofibrils. Mu-calpain treatment of the cardiac myofibril and troponin complex specifically reproduced cTnT-ND...

..The indirect flight muscle of flltH was also examined, and it was found that sarcomere length and diameter of myofibrils were abnormal...

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..Our data suggest that R448H and D705G mutations affect both CAPN3s anchorage to titin and its stability. These studies reveal a novel mechanism by which mutations that spare enzymatic activity can still lead to calpainopathy...

..In conclusion, our data suggested that an initial decrease of PKA signaling and subsequent changes in myofilament protein expression may contribute to the development of dilated cardiomyopathy in Tgalphaq*44 hearts...

In this study we investigated the molecular mechanism of glutathionylation on isolated human cardiac myofibrils using several pro-glutathionylating agents...

..a group of heterogeneous muscle disorders morphologically defined by the presence of foci of dissolution of the myofibrils, accumulation of the products of myofibrillar degradation and ectopic expression of multiple proteins...

..The aim of this communication is to provide an up-to-date overview of myofibrillar myopathies...

..Oxidative stress has been shown to increase late inward sodium current (I(Na)), reducing the net cytosolic Ca(2+) efflux...

Fast solution switching techniques in single myofibrils offer the opportunity to dissect and directly examine the sarcomeric mechanisms responsible for force generation and relaxation...

..of the mutation hcTnI(R145G) on crossbridge kinetics, force kinetics were analysed in murine cardiac myofibrils carrying either the mutant or the wild-type protein...

..We have put this idea to the test with myofibrils as a model because with these both mechanical and chemical kinetic measurements are possible...

..Skeletal muscle myofibrils were used as an example, because they contain submicron structures conveniently used to define optical ..

..These results are discussed in connection with the mechanism, by which the mechanical activity of the SBM muscle is neurally controlled...

..Chronic atrial fibrillation (cAF) is associated with atrial contractile dysfunction. Sarcomere remodeling may contribute to this contractile disorder...

..To evaluate the tissue-specific expression pattern of the 64kD human autoantigen D1, a tropomodulin-related protein that may be involved in thyroid-associated ophthalmopathy...

..Chaperone proteins specific to sarcomeric myosins have been shown to be necessary in zebrafish and invertebrates for proper muscle assembly and function...

The reorganization of myofibrils and the re-formation of intercalated discs was examined in neonatal rat cardiac muscle cells during the first 72 h of culture...

..Our results suggest that inhibition/alteration of autophagy can contribute to myofiber degeneration and weakness in muscle disorders characterized by accumulation of abnormal mitochondria and inclusions...

..The pathogenesis of this myopathy is not well understood. The morphologic hallmark is myofibrillar destruction with abnormal expression of numerous proteins, most consistently of desmin...

..of force development and relaxation upon rapid application and removal of Ca2+ was measured in bundles of few myofibrils isolated from triton X-100 skinned left ventricular trabeculae of mice (M), guinea pigs (G) and humans (H)...

..addition, immunofluorescence shows that N-RAP remains bound at the ends of isolated, detergent-treated cardiac myofibrils. These results demonstrate that N-RAP remains tightly bound to myofibrils and fasciae adherentes during ..

..changes of individual half-sarcomeres during and after stretch in actively contracting, single rabbit psoas myofibrils containing 10-30 sarcomeres...

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..the exchange of fast skeletal troponin (fsTn) for cardiac troponin (cTn) were measured in rabbit fast skeletal myofibrils. Electrophoretic analysis of myofibril suspensions indicated that replacement of fsTnC or exchange of fsTn with ..

..The myofibroblast cell line BHK-21/C13 was described to assemble myofibrils in culture. We have now characterized the sub-line BHK-21-Bi, which bears a small deletion within the titin gene...

..However, to go through cell division, a disassembly of the contractile elements, the myofibrils, has to take place...

..the heart compensates for myofibril degeneration, transgenic mice were created that undergo progressive loss of myofibrils after birth...

..When sals is knocked down by RNAi, primary muscles display thin myofibrils with shortened sarcomeres and increased sarcomere number...

..The results presented here show that desmin is essential to maintain the structural integrity of highly solicited skeletal muscle...

..It is comparable in its structure to titin, which has been implicated as a scaffold during vertebrate myofibrillogenesis...

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..Although pointed-end capping by Tmod controls thin filament lengths in assembled myofibrils, its role in length specification during de novo myofibril assembly is not established...

..We show that isolated psoas myofibrils respond to a stretch-hold protocol with a characteristic force decay that becomes more pronounced following ..

..alleles have complex myofibrillar defects, whereas Mhc36B-/+; Act88F-/+ double heterozygotes have nearly normal myofibrils. These results imply that most defects observed in single heterozygotes are due to filament imbalances, not ..

Assembly and maintenance of myofibrils require dynamic regulation of the actin cytoskeleton...

..of these proteins, short spaced alpha-actinin dots adjoined each other and aligned with Z bands of neighboring myofibrils. It appears that both the difference in exchangeability between actin and alpha-actinin molecules and the ..

..In contrast, reduced expression of the TnH isoforms has an unexpectedly mild effect on IFM structure and function...

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..We propose that D-Titin is instrumental in the development of the two defining features of striated muscle: the formation of multi-nucleate syncitia and the organization of actin-myosin filaments into striated arrays...

..The ultrastructure of myofibrils also showed disturbed arrangements of myofilaments and a disorganized contractile apparatus in denervated muscle...

..Our data suggest that enhanced diaphragm protein degradation through the ubiquitin-proteasome pathway plays a role in loss of contractile protein and, consequently, failure of the diaphragm to generate force...

..Therefore, there is no effect of menstrual cycle phase, at rest or in response to an acute bout of exercise, on myofibrillar protein synthesis and muscle collagen synthesis in women...

..To address this issue, we examined the effect of heart failure on skeletal muscle myofibrillar protein content, isoform distribution and Ca2+ sensitivity...

..SHG from isolated myofibrils is abolished by extraction of myosin, but is unaffected by removal or addition of actin filaments...

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To study the dynamics of individual half-sarcomeres in striated muscle contraction, myofibrils prepared from rabbit psoas muscle and left ventricles of guinea pig were immunostained with two conjugated antibody complexes consisting of a ..

..We measured passive force enhancement in troponin C (TnC)-depleted myofibrils in which active force production was completely eliminated...

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..We propose a model in which projectin extends from the Z-band to the lateral borders of the A-band. The PEVK-like domain and a series of Ig domains spanning the intervening I-band may provide the elastic properties of projectin...

..skeletal myotubes and non-muscle cells lead to the localization of these cardiac z-repeats in the Z-bands of the myofibrils and the dense bodies of the stress fibers...

..The active component is associated with the cross-bridge kinetics, and the passive component is associated with a calcium-dependent increase in titin stiffness...

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..coupled to chicken TPM1alpha and chicken TPM1kappa and compared their localizations in premyofibrils and mature myofibrils. We used the technique of fluorescence recovery after photobleaching (FRAP) to compare the dynamics of TPM1alpha ..

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..Further preliminary studies show that M-RIP colocalizes with myofibrils in VSMCs, and MRIP itself is a Rho-kinase substrate...

..This truncated slow TnT cannot incorporate into myofibrils and is degraded inside the myocyte...

..This truncated slow TnT cannot incorporate into myofibrils and is degraded inside the myocyte...

..of cTnT selectively removes the N-terminal variable region and keeps the remaining conserved structure in the myofibrils with functional consequences...

..Because intact myofibrils are not degraded by the proteasome, it is possible that actin and myosin are dissociated from the myofibrils ..

..protein at amino acid 179 We have shown that the truncated slow TnT is degraded and not incorporated into the myofibrils, consistent with the recessive inheritance of the disease The ANM phenotypes include tremors, contractures and ..

..and longitudinal mechanical properties of the diaphragm, and the strength of the mechanical linkage between myofibrils and the plasma membrane is determined primarily by these proteins; and (3) the mechanical coupling between ..

Costameres are structures at the surface of striated muscle that align the sarcolemma regularly with nearby myofibrils and transmit contractile force laterally, through the membrane to the extracellular matrix...

..development, because homozygous embryos (c/c) form hearts that are deficient in tropomyosin, lack organized myofibrils, and fail to beat...

..the sarcolemma of FSHD muscle has frequent interruptions in its membrane skeleton, is separated from the nearest myofibrils by a considerable gap, and is organized irregularly, and most closely resembles the sarcolemma of slow twitch ..

..integrity and tensile strength to the myocardium critical to maintaining the alignment of myocytes and myofibrils, and the overall geometry of the left ventricle...

..recessive (c/c) mutant embryos do not beat, as they are deficient in tropomyosin and do not contain organized myofibrils. However, the defect can be corrected by culturing the mutant hearts in the presence of normal anterior endoderm ..

..We have shown that the truncated slow TnT is degraded and not incorporated into the myofibrils, consistent with the recessive inheritance of the disease...

..We have shown that the truncated slow TnT is degraded and not incorporated into the myofibrils, consistent with the recessive inheritance of the disease...

..Phosphorylation of MTJ structural proteins(s) results in dissociation of myofibrils from the MTJ membrane...

..assemblies in striated muscle cells that circumferentially align in register with the Z disk of peripheral myofibrils and physically couple force-generating sarcomeres with the sarcolemma...