Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026850 (muscular dystrophy)
 5,870 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Autosomal dominant Emery-Dreifuss muscular dystrophy is caused by mutations in the LMNA gene, which encodes lamin A and lamin C. Mutations in this gene also give rise to limb girdle muscular dystrophy type 1B, dilated cardiomyopathy with atrioventricular conduction defect and Dunnigan-type partial lipodystrophy. The properties of the mutant lamins that cause muscular dystrophy, lipodystrophy and dilated cardiomyopathy are not known. We transfected C2C12 myoblasts with cDNA encoding wild-type lamin A and 15 mutant forms found in patients affected by these diseases. Immunofluorescence microscopy showed that four mutants, N195K, E358K, M371K and R386K, could have a dramatically aberrant localization, with decreased nuclear rim staining and formation of intranuclear foci. The distributions of endogenous lamin A/C, lamin B1 and lamin B2 were also altered in cells expressing these four mutants and three of them caused a loss of emerin from the nuclear envelope. In the yeast two-hybrid assay, the 15 lamin A mutants studied interacted with themselves and with wild-type lamin A and lamin B1. Pulse-chase experiments showed no decrease in the stability of several representative lamin A mutants compared with wild-type. These results indicate that some lamin A mutants causing disease can be aberrantly localized, partially disrupt the endogenous lamina and alter emerin localization, whereas others localize normally in transfected cells.
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PMID:Properties of lamin A mutants found in Emery-Dreifuss muscular dystrophy, cardiomyopathy and Dunnigan-type partial lipodystrophy. 1179 9

Nuclear lamins are components of the nuclear lamina, a structural scaffolding for the cell nucleus. Defects in lamins A and C cause an array of human diseases, including muscular dystrophy, lipodystrophy, and progeria, but no diseases have been linked to the loss of lamins B1 or B2. To explore the functional relevance of lamin B2, we generated lamin B2-deficient mice and found that they have severe brain abnormalities resembling lissencephaly, with abnormal layering of neurons in the cerebral cortex and cerebellum. This neuronal layering abnormality is due to defective neuronal migration, a process that is dependent on the organized movement of the nucleus within the cell. These studies establish an essential function for lamin B2 in neuronal migration and brain development.
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PMID:Abnormal development of the cerebral cortex and cerebellum in the setting of lamin B2 deficiency. 2036 May 57

Laminopathies are genetic diseases due to mutations or altered post-translational processing of nuclear envelope/lamina proteins. The majority of laminopathies are caused by mutations in the LMNA gene, encoding lamin A/C, but manifest as diverse pathologies including muscular dystrophy, lipodystrophy, neuropathy, and progeroid syndromes. Lamin-binding proteins implicated in laminopathies include lamin B2, nuclear envelope proteins such as emerin, MAN1, LBR, and nesprins, the nuclear matrix protein matrin 3, the lamina-associated polypeptide, LAP2alpha and the transcriptional regulator FHL1. Thus, the altered functionality of a nuclear proteins network appears to be involved in the onset of laminopathic diseases. The functional interplay among different proteins involved in this network implies signaling partners. The signaling effectors may either modify nuclear envelope proteins and their binding properties, or use nuclear envelope/lamina proteins as platforms to regulate signal transduction. In this review, both aspects of lamin-linked signaling are presented and the major pathways so far implicated in laminopathies are summarized.
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PMID:Laminopathies and lamin-associated signaling pathways. 2140 May 69

Neuronal aging involves a progressive decline in cognitive abilities and loss of motor function. Mutations in human Lamin genes (LMNA, LMNB1, LMNB2) lead to a wide-range of diseases including muscular dystrophy, peripheral neuropathy and progeria. Here we investigate the role of neuronal Lamin in regulating age-related phenotypes. Neuronal targeting of Lamin led to shortened lifespan, progressive impairment of motor function and loss of dopaminergic (DA) neurons within the protocerebral anterior medial (PAM) cluster in the Drosophila melanogaster brain. Loss of neuronal Lamin caused an age-related decline in neural physiology, with slower neurotransmission and increased chance of motor circuit failure with age. Unexpectedly, Lamin-dependent decline in motor function was specific for the chemical synapses of the dorsal longitudinal muscle (DLM). Together these findings highlight a central role for Lamin dysfunction in regulating neuronal survival and motor circuit physiology during aging.
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PMID:Neuronal Lamin regulates motor circuit integrity and controls motor function and lifespan. 3122 90