Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
65,361 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The interaction of caldesmon with certain Ca-binding proteins was investigated by means of electrophoresis under non-denaturating conditions. In the presence of Ca2+ calmodulin, troponin C and S-100 protein form a complex with caldesmon. No complex formation takes place in the absence of Ca2+. Lactalbumin and pike parvalbumin (pI4.2) do not interact with caldesmon independently of Ca-concentration. Both S-100 protein and calmodulin effectively inhibit phosphorylation of caldesmon by Ca-phospholipid-dependent protein kinase. At low ionic strength S-100 protein reverses the inhibitory action of caldesmon on the skeletal muscle acto-heavy meromyosin ATPase more effectively than calmodulin. It is supposed that in certain tissues and cell compartments the proteins belonging to the S-100 family are able to substitute for calmodulin in the caldesmon-dependent regulation of actin and myosin interaction.
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PMID:Interaction of smooth muscle caldesmon with S-100 protein. 253 Oct 95

This study compares changes in contractile properties, parvalbumin content, and Ca2+-uptake by the sarcoplasmic reticulum (SR) of low-frequency stimulated rat and rabbit tibialis anterior (TA) muscles. Time to peak tension increased 1.8-fold in 35-day stimulated rabbit TA, while no change occurred in rat TA. Isometric twitch tension increased 2-fold in rabbit TA, but was unaltered in rat TA. Parvalbumin (PA) content was more than 90% reduced in rabbit TA, but only 60% in rat TA after 35 days. At this time, PA content of the stimulated rat TA was still higher than that of normal rabbit TA. Taking into account the suggested role of PA as a cytosolic Ca2+ buffer, its decrease could lead to an impaired free Ca2+-decay with a prolonged active state and a higher tension output during a single twitch. This would explain why chronic stimulation led to an increase in isometric twitch tension in rabbit TA, but not in rat TA. The 1.6-fold rise in half-relaxation time of 35-day stimulated rat and rabbit TA most likely resulted from a 50% reduced Ca2+-uptake by the SR, due to a still unknown modification of the Ca2+-transport ATPase.
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PMID:Relations between chronic stimulation-induced changes in contractile properties and the Ca2+-sequestering system of rat and rabbit fast-twitch muscles. 281 40

The inhibitory effects of Ca2+-binding proteins on tyrosine phosphorylation of p36 protein isolated from bovine intestinal epithelium by immunoprecipitated p130fps were investigated. S-100 protein dose dependently inhibited the p36 phosphorylation, and calmodulin weakly depressed the phosphorylation, whereas parvalbumin and troponin C had no significant effects. The S-100 preparation purified from bovine brain did not contain phosphatase activity or ATPase activity. The concentration of ATP did not affect the S-100-mediated inhibition of phosphorylation but the substrate protein, p36, reversed the inhibition. S-100 similarly inhibited the tyrosine phosphorylation of p36 by p60src but did not affect the p36 phosphorylation by protein kinase C. S-100 inhibited the tyrosine kinase activity of p130fps using the other substrates tested as well. These results suggest that S-100 interacts with the substrate binding site of retroviral tyrosine-specific protein kinases and may play a regulatory role in the tyrosine phosphorylation.
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PMID:Modulation of tyrosine phosphorylation of p36 and other substrates by the S-100 protein. 283 78

Tissue contents of the sarcoplasmic-reticulum Ca2+-ATPase (Ca2+ +Mg2+-dependent ATPase), of calsequestrin and of parvalbumin were immunochemically quantified in homogenates of fast- and slow-twitch muscles of embryonic, maturing and adult rabbits. Unlike parvalbumin, Ca2+-ATPase and calsequestrin were expressed in embryonic muscles. Presumptive fast-twitch muscles displayed higher contents of these two proteins than did presumptive slow-twitch muscles. Calsequestrin steeply increased before birth and reached adult values in the two muscle types 4 days after birth. The main increase in Ca2+-ATPase occurred during the first 2 weeks after birth. Denervation of postnatal fast- and slow-twitch muscles decreased calsequestrin to amounts typical of embryonic muscle and suppressed further increases of Ca2+-ATPase. Denervation caused slight decreases in Ca2+-ATPase in adult fast-twitch, but not in slow-twitch, muscles, whereas calsequestrin was greatly decreased in both. Chronic low-frequency stimulation induced a rapid decrease in parvalbumin in fast-twitch muscle, which was preceded by a drastic decrease in the amount of its polyadenylated RNA translatable in vitro. Tissue amounts of Ca2+-ATPase and calsequestrin were essentially unaltered up to periods of 52 days stimulation. These results indicate that in fast- and slow-twitch muscles different basal amounts of Ca2+-ATPase and calsequestrin are expressed independent of innervation, but that neuromuscular activity has a modulatory effect. Conversely, the expression of parvalbumin is greatly enhanced by phasic, and drastically decreased by tonic, motor-neuron activity.
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PMID:Neural control of gene expression in skeletal muscle. Calcium-sequestering proteins in developing and chronically stimulated rabbit skeletal muscles. 288 May 79

The extensor digitorum longus (EDL) muscle was cross-reinnervated by the soleus (SOL) nerve, leading to the well-known transformation toward a slow muscle. Nine weeks after the operation, the quantitative analysis of the Ca2+-binding protein, parvalbumin (PV), using high-performance liquid chromatography, showed a threefold reduction of PV in the cross-reinnervated EDL muscle. Denervation of the EDL muscle, which leads to an increase of the half-relaxation time, resulted in a 20% decrease of the PV concentration within 4 days. This significant lower PV level was detectable prior to any change of the myofibrillar adenosine triphosphatase (ATPase). Normal PV concentrations were reached after 9 weeks following self-reinnervation of the EDL muscle. The experiments support the view that PV is involved in the relaxation of rat fast skeletal muscles and that its expression is dependent on nerve-muscle interaction. Since PV changes preceded histochemical changes after denervation, this protein may be a sensitive marker for early stages of neuromuscular disturbances.
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PMID:Parvalbumin in cross-reinnervated and denervated muscles. 293 37

Antibodies directed against purified Ca-ATPase from sarcoplasmic reticulum, calsequestrin and parvalbumin from rabbit fast-twitch muscle were raised in sheep. The specificity of the antibodies was shown by immunoblot analysis and by enzyme-linked immunoadsorbent assays (ELISAs). IgG against the sarcoplasmic reticulum Ca-ATPase inhibited the catalytic activities of Ca-ATPase from fast-twitch (psoas, tibialis anterior) and slow-twitch (soleus) muscles to the same degree. In non-equilibrium competitive ELISAs the anti(Ca-ATPase) IgG displayed a slightly higher affinity for the Ca-ATPase from fast-twitch muscle than for that from slow-twitch muscle. This suggests a fiber-type-specific polymorphism of the sarcoplasmic reticulum Ca-ATPase. Quantification of Ca-ATPase, calsequestrin and parvalbumin in various rabbit skeletal muscles of histochemically determined fiber composition was achieved by sandwich ELISA. Ca-ATPase was found to be 6-7 times higher in fast than in slow-twitch muscles. A slightly higher concentration was found in fast-twitch muscles with a higher percentage of IIb fibers when compared with fast-twitch muscles with a higher percentage of IIa fibers. Thus Ca-ATPase is distributed as follows, IIb greater than or equal to IIa much greater than I. Calsequestrin was uniformly distributed in fast-twitch muscles independently of their IIa/IIb fiber ratio and displayed 50% lower concentrations in slow than in fast-twitch muscles (IIb = IIa greater than I). Parvalbumin contents were 200-300-fold higher in fast than in slow-twitch muscles. Significantly lower parvalbumin concentrations were found in fast-twitch muscles with a higher percentage of IIa fibers than in fast-twitch muscles with a higher percentage of IIb fibers (IIb greater than IIa much greater than I).
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PMID:Immunochemical quantification of sarcoplasmic reticulum Ca-ATPase, of calsequestrin and of parvalbumin in rabbit skeletal muscles of defined fiber composition. 293 50

Ca2+ and Mg2+ movements across the sarcoplasmic reticulum (SR) of frog skeletal muscle fibers were measured in situ by electron probe microanalysis of muscles rapidly frozen following a tetanus. At 400 ms following a 1.2-s tetanus at room temperature, the force had relaxed to base-line, and 0.3 mmol of Ca2+/liter of cytoplasmic H2O had been pumped by the SR, indicating that the in situ pumping of the SR Ca-ATPase is sufficiently high to account for the removal of Ca2+ from the Ca2+-specific sites of troponin (0.18 mmol of Ca2+-specific sites/liter of cytoplasmic H2O) and for the rate of relaxation from a tetanus at room temperature. The half-time of the return of the total 1.0 mmol of Ca2+/liter of cytoplasmic H2O released during a tetanus was 1.1 s, comparable to the slow Koff rate of Ca2+ from (carp) parvalbumin (1.0 s-1) and consistent with the hypothesis that the return of this Ca2+ to the terminal cisternae is rate-limited by the Ca2+ off-rate from parvalbumin. The return of the Mg2+ taken up by the terminal cisternae during a tetanus to resting levels was significantly slower than the time course of the Ca2+ movements, suggesting that the Mg2+ permeability of the SR in situ is low and may be transiently increased during tetanic stimulation.
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PMID:Electron probe X-ray microanalysis of post-tetanic Ca2+ and Mg2+ movements across the sarcoplasmic reticulum in situ. 315 52

The pattern of spontaneous skeletal muscle degeneration and clinical recovery hindlimb muscles of the mdx mutant mouse was examined for functional and metabolic confirmation of apparent structural regeneration. The contractile properties, histochemical staining and myosin light chain and parvalbumin contents of extensor digitorum longus (EDL) and soleus (Sol) muscles of mdx and age-matched control mice were studied at 3-4 and 32 weeks. Histochemical staining (myofibrillar ATPase and NADH-tetrazolium reductase) revealed no significant change in slow-twitch-oxidative (SO) or fast-twitch-oxidative-glycolytic (FOG) fibre type proportions in mdx Sol apart from the normal age-related increase in SO fibres. At 32 weeks mdx EDL, however, showed significantly smaller fast-twitch-glycolytic (FG) and larger FOG proportions than those in control EDL. These fibre type distributions were confirmed by differential staining with antibodies to myosin slow-twitch and fast-twitch heavy chain isozymes. Frequency distribution of cross-sectional area for each fibre type showed a wider than normal range of areas especially in FOG fibres of mdx Sol, and FG fibres of mdx EDL, supporting previous observations using autoradiography of myofibre regeneration. Isometric twitch and tetanic tensions in Sol were significantly less than in controls at 4 weeks, but by 32 weeks, values were not different from age-matched controls. In mdx EDL at 3 weeks, twitch and tetanus tensions were significantly less, and time-to-peak twitch tensions were significantly faster than in control EDL. By 32 weeks, mdx EDL twitch and tetanus tensions expressed relative to muscle weight continued to be significantly lower than in age-matched controls, despite normal absolute tensions. The maximum velocity of shortening in 32-week mdx EDL was significantly lower than in control EDL. Myosin light chain distribution in mdx Sol exhibited significantly less light chain 2-slow (LC2s) and more light chain 1b-slow(LC1bs) at 32 weeks than age-matched control Sol. Gels of EDL from 32-week-old mdx mice showed significantly less light chain 2-fast-phosphorylated (LC2f-P) and light chain 3-fast (LC3f) and significantly more light chain 1-fast (LC1f) and light chain 2-fast (LC2f), but normal parvalbumin content compared to age-matched controls. These observations suggest that mdx hindlimb muscles are differentially affected by the disease process as it occurs in murine models of dystrophy. However, the uniqueness of mdx Sol and to a lesser extent EDL is that they also undergo an important degree of functional regeneration which is able to compensate spontaneously for degenerative influences of genetic origin.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Functional regeneration in the hindlimb skeletal muscle of the mdx mouse. 320 90

Effects of a long-term, high intensity training program upon histochemically assessed myofibrillar actomyosin ATPase, myosin composition, peptide pattern of sarcoplasmic reticulum (SR), and parvalbumin content were analysed in muscles from the same rats which were used in a previous study (Green et al. 1983). Following 15 weeks of extreme training, an increase in type I and type II A fibres and a decrease in type II B fibres occurred both in plantaris and extensor digitorum longus (EDL) muscles. In the deep portion of vastus lateralis (VLD), there was a pronounced increase from 10 +/- 5% to 27 +/- 11% in type I fibres. No type I fibres were detected in the superficial portion of vastus lateralis (VLS) both in control and trained animals. An increase in slow type myosin light chains accompanied the histochemically observed fibre type transition in VLD. Changes in the peptide pattern of SR occurred both in VLS and VLD and suggested a complete transition from type II B to II A in VLS and from type II A to I in VLD. A complete type II A to I transition in the VLD was also suggested by the failure to detect parvalbumin in this muscle after 15 weeks of training. Changes in parvalbumin content and SR tended to precede the transitions in the myosin light chains. Obviously, high intensity endurance training is capable of transforming specific characteristics of muscle fibres beyond the commonly observed changes in the enzyme activity pattern of energy metabolism. The time courses of the various changes which are similar to those in chronic nerve stimulation experiments, indicate that various functional systems of the muscle fibre do not change simultaneously.
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PMID:Exercise-induced fibre type transitions with regard to myosin, parvalbumin, and sarcoplasmic reticulum in muscles of the rat. 623 80

In myotonic ADR mice that are homozygous for a defect in the muscular chloride channel gene adr/Clc-1, the hyperexcitability of fast muscles is associated with secondary changes in gene expression and fibre type composition. cDNA clones derived from a set of genes down regulated in fast muscles of the myotonic ADR mouse were isolated by a subtractive cloning procedure. A total of 1200 clones were analysed for high expression in fast muscle of wild type and low expression in mutant mouse. Differential transcript levels were verified by northern blot hybridizations. The identities of the corresponding transcripts were determined by sequencing as myosin heavy chain IIB, alpha-tropomyosin, troponin C, a Ca2+ ATPase and parvalbumin mRNAs. Of these, mRNAs for parvalbumin and myosin heavy chain IIB were drastically downregulated in myotonic muscle (to < 10% of control). A full length cDNA clone for skeletal muscle alpha-tropomyosin was homologous to the mouse fibroblast tropomyosin isoform 2, except for the portion encoding the alpha-tropomyosin specific amino acids 258-284. A cDNA derived from the 1100 nucleotide parvalbumin transcript was cloned and the sequence for the as yet unknown 3' extended trailer, generated by alternative polyadenylation, was determined.
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PMID:Subtractive cDNA cloning as a tool to analyse secondary effects of a muscle disease. Characterization of affected genes in the myotonic ADR mouse. 752 80


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