Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026838 (spasticity)
 6,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary spongiform dystrophy in young children is characterised by macrocephaly with spasticity, convulsions and ultimately a decerebrate state and diffuse electroencephalographic changes. Histological examination of the brain remains essential for its diagnosis. A review of the ultrastructural studies reported by various authors complements the findings obtained by conventional histology. We have thus endeavoured to determine whether van Bogaert-Bertrand's disease is to be considered as congenital or acquired. The anatomical findings in 3 cases together with the descriptions of other authors lead us to the following conclusions: -that the spongiform changes may be due to an osmolar disequilibrium in which the ATPase-Na/K relation with mitochondrial abnormalities is yet unclear. -that the constant finding of Alzheimer type II cells is certainly an indication of intra-astrocytic malfunction. -that the oedema blocks both myelin synthesis and its coiling into lamellae. Case 1, which showed a long survival compared to others described (about 4 years), enabled us to study terminal lesions. Sub-cortical zones, in both cerebrum and cerebellum, contained neither myelin nor spongiform cavities, but, on the other hand, showed a compact glio-fibrillosis with large vesicles and oligodendroglia of increased density. We have interpreted these lesions, progressively replaced by spongiosis deeper in the cortex, as evidence of retracted scar tissue. Differences found between cerebral weights seem to confirm this hypothesis.
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PMID:[Hereditary spongiform dystrophy in young children (Canavan: van Bogaert-Bertrand)]. 127 Oct 80

Autosomal dominant hereditary spastic paraplegia (AD-HSP) is a genetically heterogeneous neurodegenerative disorder characterized by progressive spasticity of the lower limbs. Among the four loci causing AD-HSP identified so far, the SPG4 locus at chromosome 2p2-1p22 has been shown to account for 40-50% of all AD-HSP families. Using a positional cloning strategy based on obtaining sequence of the entire SPG4 interval, we identified a candidate gene encoding a new member of the AAA protein family, which we named spastin. Sequence analysis of this gene in seven SPG4-linked pedigrees revealed several DNA modifications, including missense, nonsense and splice-site mutations. Both SPG4 and its mouse orthologue were shown to be expressed early and ubiquitously in fetal and adult tissues. The sequence homologies and putative subcellular localization of spastin suggest that this ATPase is involved in the assembly or function of nuclear protein complexes.
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PMID:Spastin, a new AAA protein, is altered in the most frequent form of autosomal dominant spastic paraplegia. 1061 Jan 78

Autosomal dominant hereditary spastic paraplegia (AD-HSP) is a genetically heterogeneous neurodegenerative disorder characterised by progressive spasticity of the lower limbs. The SPG4 locus at 2p21-p22 accounts for 40-50% of all AD-HSP families. The SPG4 gene was recently identified. It is ubiquitously expressed in adult and foetal tissues and encodes spastin, an ATPase of the AAA family. We have now identified four novel SPG4 mutations in German AD-HSP families, including one large family for which anticipation had been proposed. Mutations include one frame-shift and one missense mutation, both affecting the Walker motif B. Two further mutations affect two donor splice sites in introns 12 and 16, respectively. RT-PCR analysis of both donor splice site mutations revealed exon skipping and reduced stability of aberrantly spliced SPG4 mRNA. All mutations are predicted to cause loss of functional protein. In conclusion, we confirm in German families that SPG4 mutations cause AD-HSP. Our data suggest that SPG4 mutations exert their dominant effect not by gain of function but by haploinsufficiency. If a threshold level of spastin were critical for axonal preservation, such threshold dosage effects might explain the variable expressivity and incomplete penetrance of SPG4-linked AD-HSP.
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PMID:Hereditary spastic paraplegia caused by mutations in the SPG4 gene. 1103 77

Hereditary spastic paraplegia (HSP) is characterized by progressive weakness and spasticity of the lower limbs, caused by the specific degeneration of the corticospinal tracts, the longest axons in humans. Most cases of the autosomal dominant form of the disease are due to mutations in the SPG4 gene, which encodes spastin, an ATPase belonging to the AAA family. The cellular pathways in which spastin operates and its role in causing degeneration of motor axons are currently unknown. By expressing wild-type or ATPase-defective spastin in several cell types, we now show that spastin interacts dynamically with microtubules. Spastin association with the microtubule cytoskeleton is mediated by the N-terminal region of the protein, and is regulated through the ATPase activity of the AAA domain. Expression of all the missense mutations into the AAA domain, which were previously identified in patients, leads to constitutive binding to microtubules in transfected cells and induces the disappearance of the aster and the formation of thick perinuclear bundles, suggesting a role of spastin in microtubule dynamics. Consistently, wild-type spastin promotes microtubule disassembly in transfected cells. These data suggest that spastin may be involved in microtubule dynamics similarly to the highly homologous microtubule-severing protein, katanin. Impairment of fine regulation of the microtubule cytoskeleton in long axons, due to spastin mutations, may underlie pathogenesis of HSP.
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PMID:Spastin, the protein mutated in autosomal dominant hereditary spastic paraplegia, is involved in microtubule dynamics. 1180 24

Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous condition, characterised principally by progressive spasticity of the lower limbs. Forty percent of autosomal dominant (AD) pedigrees show linkage to the SPG4 locus on chromosome 2, which encodes spastin, an ATPase associated with diverse cellular activities (AAA) protein. We have performed a clinical and genetic study of three AD-HSP families linked to SPG4. Sequencing revealed three novel causative mutations. Two of the mutations were located in exon 5 (a 1-base pair (bp) insertion and a 5-bp deletion), resulting in frameshift and premature termination of translation, with the predicted protein lacking the entire AAA functional domain. The 5-bp deletion was associated with a later onset and mild cerebellar features. The third mutation was a 3-bp deletion in exon 9, resulting in the loss of a highly conserved phenylalanine residue within the AAA cassette and an apparently milder phenotype. This is the first example of a deletion of an amino acid in spastin.
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PMID:Three novel spastin (SPG4) mutations in families with autosomal dominant hereditary spastic paraplegia. 1216 96

Hereditary spastic paraparesis (HSP) belongs to a group of genetically and clinically heterogeneous disorders characterised by progressive spasticity of the legs and hyperreflexia. A further clinical distinction is drawn between pure and complicated HSP depending on the presence of other neurological and non-neurological signs. HSP may be inherited either as autosomal dominant, recessive, or X-linked. Twenty-two loci have been identified and additional ones are envisaged. In autosomal dominant HSP, 11 loci (five genes) have been identified, the most prevalent of which is linked to chromosome 2p, coding for spastin, an ATPase belonging to the AAA family (acronym of 'ATPase associated with diverse cellular activities'). Spastin is a nuclear protein, present in neurons, but not in glial cells, and seems to be involved in microtubule dynamics. Nonsense and frameshift mutations result in a reduced amount of spastin.
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PMID:[From gene to disease; spastin and hereditary spastic paraparesis]. 1497 10

Hereditary spastic paraplegias (HSPs), a group of neurodegenerative disorders characterized by lower-extremity spasticity and weakness, are most commonly caused by mutations in the spastin gene, which encodes a AAA+ ATPase related to the microtubule-severing protein katanin. A Drosophila homolog of spastin (D-spastin) was identified recently, and D-spastin RNAi-treated or genetic null flies show neurological defects, and protein overexpression decreases the density of cellular microtubules. Elucidating spastin's function and disease mechanism will require a more detailed understanding of its structure and biochemical mechanism. Here, we have investigated the effects of D-spastin, individual D-spastin domains, and D-spastin proteins bearing disease mutations on microtubules in cellular and in vitro assays. We show that D-spastin, like katanin, displays ATPase activity and uses energy from ATP hydrolysis to sever and disassemble microtubules; disease mutations abolish or partially interfere with these activities.
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PMID:The Drosophila homologue of the hereditary spastic paraplegia protein, spastin, severs and disassembles microtubules. 1582 37

Clostridium botulinum, a Gram-positive, anaerobic spore-forming bacteria, is distinguished by its significant clinical applications as well as its potential to be used as bioterror agent. Growing cells secrete botulinum neurotoxin (BoNT), the most poisonous of all known poisons. While BoNT is the causative agent of deadly neuroparalytic botulism, it also serves as a remarkably effective treatment for involuntary muscle disorders such as blepharospasm, strabismus, hemifacial spasm, certain types of spasticity in children, and other ailments. BoNT is also used in cosmetology for the treatment of glabellar lines, and is well-known as the active component of the anti-aging medications Botox and Dysport. In addition, recent reports show that botulinum neurotoxin can be used as a tool for pharmaceutical drug delivery. However, BoNT remains the deadliest of all toxins, and is viewed by biodefense researchers as a possible agent of bioterrorism (BT). Among seven serotypes, C. botulinum type A is responsible for the highest mortality rate in botulism, and thus has the greatest potential to act as biological weapon. Genome sequencing of C. botulinum type A Hall strain (ATCC 3502) is now complete, and has shown the genome size to be 3.89 Mb with a G+C content of approximately 28.2%. The bacterium harbors a 16.3 kb plasmid with a 26.8% G+C content--slightly lower than that of the chromosome. Most of the virulence factors in C. botulinum are chromosomally encoded; bioinformatic analysis of the genome sequence has shown that the plasmid does not harbor toxin genes or genes for related virulence factors. Interestingly, the plasmid does harbor genes essential to replication, including dnaE, which encodes the alpha subunit of DNA polymerase III which has close similarity with its counterpart in C. perfringens strain 13. The plasmid also contains similar genes to those that encode the ABC-type multidrug transport ATPase, and permease. The presence of ABC-type multidrug transport ATPase, and permease suggests putative involvement of efflux pumps in bacteriocin production, modification, and export in C. botulinum. The C. botulinum plasmid additionally harbors genes for LambdaBa04 prophage and site-specific recombinase that are similar to those found in the Ames strain of Bacillus anthracis; these genes and their products may play a role in genomic rearrangement. Completion of genome sequencing for C. botulinum will provide an opportunity to design genomic and proteomic-based systems for detecting different serotypes of C. botulinum strains in the environment. The completed sequence may also facilitate identification of potential virulence factors and drug targets, as well as help characterize neurotoxin-complexing proteins, their polycistronic expression, and phylogenetic relationships between different serotypes.
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PMID:Clostridium botulinum: a bug with beauty and weapon. 1583 1

Hereditary spastic paraplegias (HSPs) are neurodegenerative diseases caused by mutations in more than 20 genes, which lead to progressive spasticity and weakness of the lower limbs. The most frequently mutated gene causing autosomal dominant HSP is SPG4, which encodes spastin, a protein that belongs to the family of ATPases associated with various cellular activities (AAAs). A number of studies have suggested that spastin regulates microtubule dynamics. We have studied the ATPase activity of recombinant human spastin and examined the effect of taxol-stabilized microtubules on this activity. We used spastin translated from the second ATG and provide evidence that this is the physiologically relevant form. We showed that microtubules enhance the ATPase activity of the protein, a property also described for katanin, an AAA of the same spastin subgroup. Furthermore, we demonstrated that human spastin has a microtubule-destabilizing activity and can bundle microtubules in vitro, providing new insights into the molecular pathogenesis of HSP.
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PMID:Human spastin has multiple microtubule-related functions. 1621 33

Hereditary spastic paraplegias (HSPs) are a group of neurodegenerative diseases characterized by progressive weakness and spasticity of the lower limbs. Dominant mutations in the human SPG4 gene, encoding spastin, are responsible for the most frequent form of HSP. Spastin is an ATPase that binds microtubules and localizes to the spindle pole and distal axon in mammalian cell lines. Furthermore, its Drosophila homolog, Drosophila spastin (Dspastin), has been recently shown to regulate microtubule stability and synaptic function at the Drosophila larval neuromuscular junction. Here we report the generation of a spastin-linked HSP animal model and show that in Drosophila, neural knockdown of Dspastin and, conversely, neural overexpression of Dspastin containing a conserved pathogenic mutation both recapitulate some phenotypic aspects of the human disease, including adult onset, locomotor impairment, and neurodegeneration. At the subcellular level, neuronal expression of both Dspastin RNA interference and mutant Dspastin cause an excessive stabilization of microtubules in the neuromuscular junction synapse. In addition, we provide evidence that administration of the microtubule targeting drug vinblastine significantly attenuates these phenotypes in vivo. Our findings demonstrate that loss of spastin function elicits HSP-like phenotypes in Drosophila, provide novel insights into the molecular mechanism of spastin mutations, and raise the possibility that therapy with Vinca alkaloids may be efficacious in spastin-associated HSP and other disorders related to microtubule dysfunction.
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PMID:Disease-related phenotypes in a Drosophila model of hereditary spastic paraplegia are ameliorated by treatment with vinblastine. 1627 9


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