Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.22.54 (calpain 3)
 430 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The autosomal recessive limb-girdle muscular dystrophies (AR-LGMDs) are a heterogeneous group of disorders of progressive weakness of the pelvic and shoulder girdle musculature. The clinical course is characterized by great variability, ranging from severe forms with onset in the first decade and rapid progression resembling clinically Xp21 Duchenne muscular dystrophy (DMD) to milder forms with later onset and slower course. Eight genes are mapped for the AR-LGMDs; they are: LGMD2A (CAPN3) at 15q, LGMD2B (dysferlin) at 2p, LGMD2C (gamma-SG) at 13q, LGMD2D (alpha-SG) at 17q, LGMD2E (beta-SG) at 4q, LGMD2F (6-SG) at 5q, LGMD2G at 17q, and more recently LGMD2H at 9q. The LGMD2F (delta-SG) and LGMD2G genes were mapped in Brazilian AR-LGMD families. Linkage analysis in two unlinked families excluded the eight AR-LGMD genes, indicating that there is at least one more gene responsible for AR-LGMD. We have analyzed 140 patients (from 40 families) affected with one of seven autosomal recessive LGMD loci, that is, from LGMD2A to LGMD2G. The main observations were: 1) all LGMD2E and LGMD2F patients had a severe condition, but considerable inter- and intra-familial clinical variability was observed among patients from all other groups; 2) serum CK activities showed the highest values in LGMD2D (alpha-SG) patients among sarcoglycanopathies and LGMD2B (dysferlin) patients among nonsarcoglycanopathies; 3) comparison between LGMD2A (CAPN3) and LGMD2B (dysferlin) showed that the first have on average a more severe course and have calf hypertrophy more frequently (86% versus 13%); and 4) inability to walk on toes was observed in approximately 70% of LGMD2B patients.
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PMID:Seven autosomal recessive limb-girdle muscular dystrophies in the Brazilian population: from LGMD2A to LGMD2G. 1006 10

Autosomal recessive limb-girdle muscular dystrophies (AR LGMDs) are a genetically heterogeneous group of disorders that affect mainly the proximal musculature. There are eight genetically distinct forms of AR LGMD, LGMD 2A-H (refs 2-10), and the genetic lesions underlying these forms, except for LGMD 2G and 2H, have been identified. LGMD 2A and LGMD 2B are caused by mutations in the genes encoding calpain 3 (ref. 11) and dysferlin, respectively, and are usually associated with a mild phenotype. Mutations in the genes encoding gamma-(ref. 14), alpha-(ref. 5), beta-(refs 6,7) and delta (ref. 15)-sarcoglycans are responsible for LGMD 2C to 2F, respectively. Sarcoglycans, together with sarcospan, dystroglycans, syntrophins and dystrobrevin, constitute the dystrophin-glycoprotein complex (DGC). Patients with LGMD 2C-F predominantly have a severe clinical course. The LGMD 2G locus maps to a 3-cM interval in 17q11-12 in two Brazilian families with a relatively mild form of AR LGMD (ref. 9). To positionally clone the LGMD 2G gene, we constructed a physical map of the 17q11-12 region and refined its localization to an interval of 1.2 Mb. The gene encoding telethonin, a sarcomeric protein, lies within this candidate region. We have found that mutations in the telethonin gene cause LGMD 2G, identifying a new molecular mechanism for AR LGMD.
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PMID:Limb-girdle muscular dystrophy type 2G is caused by mutations in the gene encoding the sarcomeric protein telethonin. 1065 62

Dysferlin is the protein product of the DYSF gene mapped at 2p31, which mutations cause limb-girdle muscular dystrophy type 2B (LGMD2B) and Miyoshi myopathy. To date, nine autosomal recessive forms (AR-LGMD) have been identified: four genes, which code for the sarcoglycan glycoproteins, are associated with both mild and severe forms, the sarcoglycanopathies (LGMD2C, 2D, 2E and 2F). The other five forms, usually causing a milder phenotype are LGMD2A (calpain 3), LGMD2B (dysferlin), LGMD2G (telethonin), LGMD2H (9q31-11), and LGMD21 (19q13.3). We studied dysferlin expression in a total of 176 patients, from 166 LGMD families: 12 LGMD2B patients, 70 with other known forms of muscular dystrophies (LGMD2A, sarcoglycanopathies, LGMD2G), in an attempt to assess the effect of the primary gene-product deficiency on dysferlin. In addition, 94 still unclassified LGMD families were screened for dysferlin deficiency. In eight LGMD2B patients from five families, no dysferlin was observed in muscle biopsies, both through immunofluorescence (IF) and Western blot methodologies, while in two families, a very faint band was detected. Both patterns, negative or very faint bands, were concordant in patients belonging to the same families, suggesting that dysferlin deficiency is specific to LGMD2B. Myoferlin, the newly identified homologue of dysferlin was studied for the first time in LGMD2B patients. Since no difference was observed between patients mildly and severely affected, this protein do not seem to modify the phenotype in the present dysferlin-deficient patients. Dystrophin, sarcoglycans, and telethonin were normal in all LGMD2B patients, while patients with sarcoglycanopathies (2C, 2D, and 2E), LGMD2A, LGMD2G, and DMD showed the presence of a normal dysferlin band by Western blot and a positive pattern on IF. These data suggest that there is no interaction between dysferlin and these proteins. However, calpain analysis showed a weaker band in four patients from two families with intra-familial concordance. Therefore, this secondary deficiency of calpain in LGMD2B families, may indicate an interaction between dysferlin and calpain in muscle. Dysferlin was also present in cultured myotubes, in chorionic villus, and in the skin. Dysferlin deficiency was found in 24 out of a total of 166 Brazilian AR-LGMD families screened for muscle proteins (approximately 14%), thus representing the second most frequent known LGMD form, after calpainopathy, in our population.
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PMID:Dysferlin protein analysis in limb-girdle muscular dystrophies. 1166 64

Telethonin is a 19-kDa sarcomeric protein, localized to the Z-disc of skeletal and cardiac muscles. Mutations in the telethonin gene cause limb-girdle muscular dystrophy type 2G (LGMD2G). We investigated the sarcomeric integrity of muscle fibers in LGMD2G patients, through double immunofluorescence analysis for telethonin with three sarcomeric proteins: titin, alpha-actinin-2, and myotilin and observed the typical cross striation pattern, suggesting that the Z-line of the sarcomere is apparently preserved, despite the absence of telethonin. Ultrastructural analysis confirmed the integrity of the sarcomeric architecture. The possible interaction of telethonin with other proteins responsible for several forms of neuromuscular disorders was also analyzed. Telethonin was clearly present in the rods in nemaline myopathy (NM) muscle fibers, confirming its localization to the Z-line of the sarcomere. Muscle from patients with absent telethonin showed normal expression for the proteins dystrophin, sarcoglycans, dysferlin, and calpain-3. Additionally, telethonin showed normal localization in muscle biopsies from patients with LGMD2A, LGMD2B, sarcoglycanopathies, and Duchenne muscular dystrophy (DMD). Therefore, the primary deficiency of calpain-3, dysferlin, sarcoglycans, and dystrophin do not seem to alter telethonin expression.
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PMID:Telethonin protein expression in neuromuscular disorders. 1237 11

We have performed expression profiling to define the molecular changes in dysferlinopathy using a novel dedicated microarray platform made with 3'-end skeletal muscle cDNAs. Eight dysferlinopathy patients, defined by western blot, immunohistochemistry and mutation analysis, were investigated with this technology. In a first experiment RNAs from different limb-girdle muscular dystrophy type 2B patients were pooled and compared with normal muscle RNA to characterize the general transcription pattern of this muscular disorder. Then the expression profiles of patients with different clinical traits were independently obtained and hierarchical clustering was applied to discover patient-specific gene variations. MHC class I genes and genes involved in protein biosynthesis were up-regulated in relation to muscle histopathological features. Conversely, the expression of genes codifying the sarcomeric proteins titin, nebulin and telethonin was down-regulated. Neither calpain-3 nor caveolin, a sarcolemmal protein interacting with dysferlin, was consistently reduced. There was a major up-regulation of proteins interacting with calcium, namely S100 calcium-binding proteins and sarcolipin, a sarcoplasmic calcium regulator.
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PMID:Gene expression profiling in dysferlinopathies using a dedicated muscle microarray. 1247 Oct 55

Muscular dystrophies are a heterogeneous group of genetically determined progressive disorders of the muscle with a primary or predominant involvement of the pelvic or shoulder girdle musculature. The clinical course is highly variable, ranging from severe congenital forms with rapid progression to milder forms with later onset and a slower course. In recent years, several proteins from the sarcolemmal muscle membrane (dystrophin, sarcoglycans, dysferlin, caveolin-3), from the extracellular matrix (alpha2-laminin, collagen VI), from the sarcomere (telethonin, myotilin, titin, nebulin), from the muscle cytosol (calpain 3, TRIM32), from the nucleus (emerin, lamin A/C, survival motor neuron protein), and from the glycosylation pathway (fukutin, fukutin-related protein) have been identified. Mutations in their respective genes are responsible for different forms of neuromuscular diseases. Protein analysis using Western blotting or immunohistochemistry with specific antibodies is of the utmost importance for the differential diagnosis and elucidation of the physiopathology of each genetic disorder involved. Recent molecular studies have shown clinical inter- and intra-familial variability in several genetic disorders highlighting the importance of other factors in determining phenotypic expression and the role of possible modifying genes and protein interactions. Developmental studies can help elucidate the mechanism of normal muscle formation and thus muscle regeneration. In the last fifteen years, our research has focused on muscle protein expression, localization and possible interactions in patients affected by different forms of muscular dystrophies. The main objective of this review is to summarize the most recent findings in the field and our own contribution.
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PMID:Protein defects in neuromuscular diseases. 1271 73

Limb-girdle muscular dystrophies (LGMD) are a heterogeneous group of genetically determined disorders with a primary or predominant involvement of the pelvic or shoulder girdle musculature. The clinical course is characterized by great variability, ranging from severe forms with rapid onset and progression to very mild forms allowing affected people to have fairly normal life spans and activity levels. Sixteen loci have been so far identified, six autosomal dominant and ten autosomal recessive. Linkage analyses indicate that there is further genetic heterogeneity both for dominant as well as for recessive LGMD. The dominant forms (LGMD1) are generally milder and relatively rare, representing less than 10% of all LGMD. The autosomal recessive forms (LGMD2) are much more common, having a cumulative prevalence of 1:15,000 with a number of geographical differences. The product of ten autosomal recessive LGMD genes has so far been identified. They are: calpain-3 (LGMD2A), dysferlin (LGMD2B), alpha-sarcoglycan (LGMD2D), beta-sarcoglycan (LGMD2E), gamma-sarcoglycan (LGMD2C), delta-sarcoglycan (LGMD2F), telethonin (LGMD2G), TRIM32 (LGMD2H), fukutin-related protein (LGMD2I) and titin (LGMD2J). There are, however, at least 25% of families who can be excluded from any known locus. The present review is devoted to outline the present advancements in the molecular bases of autosomal recessive LGMD.
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PMID:Molecular bases of autosomal recessive limb-girdle muscular dystrophies. 1495 61

We report on two siblings with late-onset, limb-girdle muscular dystrophy (LGMD) inherited in an autosomal recessive manner. The LGMD was characterized by many rimmed vacuoles and reduced expression of the laminin beta1 chain in skeletal muscle. Both patients developed a progressive wasting and weakness of limb-girdle muscles in the late forties or early fifties; their facial, ocular, bulbar, and cardiac muscles were not involved. Histopathology of skeletal muscles biopsies showed typical dystrophic changes with many rimmed vacuoles. The immunoreactivity of the laminin beta1 chain was reduced in the muscle fibers, while dystrophin, sarcoglycans, beta-dystroglycan, dysferlin, and other laminin components were normally expressed. A mutation search revealed that no mutation existed in the coding region of the calpain 3, telethonin and UDP-N-acetylglucosamine 2-epimerase/N-acetylmanosamine kinase (GNE) genes. We conclude that this autosomal recessive LGMD is unknown and characterized by its late onset, rimmed vacuoles and reduction of the laminin beta1 chain in muscle fibers.
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PMID:Late-onset autosomal recessive limb-girdle muscular dystrophy with rimmed vacuoles. 1500 3

The limb-girdle muscular dystrophies are a diverse group of muscle-wasting disorders characteristically affecting the large muscles of the pelvic and shoulder girdles. Molecular genetic analyses have demonstrated causative mutations in the genes encoding a disparate collection of proteins involved in all aspects of muscle cell biology. Muscular dystrophy includes a spectrum of disorders caused by loss of the linkage between the extracellular matrix and the actin cytoskeleton. Within this are the forms of limb-girdle muscular dystrophy caused by deficiencies of the sarcoglycan complex and by aberrant glycosylation of alpha-dystroglycan caused by mutations in the fukutin-related protein gene. However, other forms of this disease have distinct pathophysiological mechanisms. For example, deficiency of dysferlin disrupts sarcolemmal membrane repair, whilst loss of calpain-3 may exert its pathological influence either by perturbation of the IkappaBalpha/NF-kappaB pathway, or through calpain-dependent cytoskeletal remodelling. Caveolin-3 is implicated in numerous cell-signalling pathways and involved in the biogenesis of the T-tubule system. Alterations in the nuclear lamina caused by mutations in laminA/C, sarcomeric changes in titin, telethonin or myotilin at the Z-disc, and subtle changes in the extracellular matrix proteins laminin-alpha2 or collagen VI can all lead to a limb-girdle muscular dystrophy phenotype, although the specific pathological mechanisms remain obscure. Differential diagnosis of these disorders requires the careful application of a broad range of disciplines: clinical assessment, immunohistochemistry and immunoblotting using a panel of antibodies and extensive molecular genetic analyses.
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PMID:Limb-girdle muscular dystrophies--from genetics to molecular pathology. 1504 7

Ankrd2 may be a link between the sarcomere and the nucleus; a similar role has recently been proposed for CARP that has a high level of structural and functional conservation with Ankrd2. Both Ankrd2 and CARP are involved in striated muscle hypertrophy. The mechanism by which muscle stretch is sensed and signals are transduced is still unknown; however, Ankrd2 and CARP could play similar roles in pathways leading to hypertrophy, the triggering mechanisms being heart pressure overload monitored by CARP and mechanical stretch in skeletal muscle monitored by Ankrd2. Recently Ankrd2 and CARP have been proposed as members of a family of muscle ankyrin repeat proteins (MARPs) that form a complex with titin, myopalladin and calpain protease p94, involved in signaling and regulation of gene expression in response to muscle stress. Here, we show that Ankrd2 is able to interact with the Z-disc protein telethonin as well as being able to interact with three transcription factors: YB-1, PML and p53. Ankrd2 binding to the ubiquitous transcription factor YB-1 can be demonstrated both in vitro and in vivo; this is not very surprising, since a similar interaction was previously described for CARP. However, the interactions with PML and p53 are unexpected new findings, with interesting implications in the Ankrd2 signaling cascade. Ankrd2 co-localizes with the transcriptional co-activator and co-repressor PML in nuclear bodies (NBs) in human myoblasts as detected by confocal immunofluorescence. Interestingly, we show that Ankrd2 not only binds the tumor suppressor protein p53 both in vitro and in vivo but also enhances the up-regulation of the p21(WAFI/CIPI) promoter by p53. Therefore, our findings strengthen the hypothesis that Ankrd2 may be involved in sensing stress signals and linking these to muscle gene regulation.
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PMID:The Ankrd2 protein, a link between the sarcomere and the nucleus in skeletal muscle. 1513 35


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