title: Human spastin has multiple microtubule-related functions.
abstract: 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.
authors.affiliation: Molecular NeuroPathobiology Laboratories, Cancer Research UK London Research Institute, Lincoln's Inn Fields Laboratories, London, UK.
authors.forename: Sara
authors.initials: S
authors.lastname: Salinas
authors.forename: Rafael E
authors.initials: RE
authors.lastname: Carazo-Salas
authors.forename: Christos
authors.initials: C
authors.lastname: Proukakis
authors.forename: J Mark
authors.initials: JM
authors.lastname: Cooper
authors.forename: Anne E
authors.initials: AE
authors.lastname: Weston
authors.forename: Giampietro
authors.initials: G
authors.lastname: Schiavo
authors.forename: Thomas T
authors.initials: TT
authors.lastname: Warner
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000266:Adenylyl Imidodiphosphate / Q000494:pharmacology; D002460:Cell Line; D004252:DNA Mutational Analysis / Q000379:methods; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005434:Flow Cytometry / Q000379:methods; D005455:Fluorescent Antibody Technique / Q000379:methods; D015870:Gene Expression / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000494:pharmacology; D006639:Histidine / Q000378:metabolism; D006801:Humans; D000074201:Katanin; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008870:Microtubules / Q000502:physiology* / Q000648:ultrastructure; D008954:Models, Biological; D008967:Molecular Biology / Q000379:methods; D016296:Mutagenesis / Q000502:physiology; D009447:Neuroblastoma; D017239:Paclitaxel / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects / Q000502:physiology; D000074181:Spastin; D013997:Time Factors; D014162:Transfection / Q000379:methods; D014404:Tubulin / Q000494:pharmacology
chemical_list: D014404:Tubulin; D049452:Green Fluorescent Proteins; D000266:Adenylyl Imidodiphosphate; C022571:adenosine 5'-O-(3-thiotriphosphate); D006639:Histidine; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D000074181:Spastin; D000074201:Katanin; C400283:SPAST protein, human; D017239:Paclitaxel