title: A new model to study spinal muscular atrophy: neurite degeneration and cell death is counteracted by BCL-X(L) Overexpression in motoneurons.
abstract: Spinal muscular atrophy (SMA) is a motoneuron disorder characterized by deletions or specific mutations in the Survival Motor Neuron gene (SMN). SMN is ubiquitously expressed and has a general role in the assembly of small nuclear ribonucleoprotein (snRNP) and pre-mRNA splicing requirements. However, in motoneuron axons SMN deficiency results in inappropriate levels of certain transcripts in the distal axon, suggesting that the specific susceptibility of motoneurons to SMN deficiency is related to a specialized function in these cells. Although mouse models of SMA have been generated and are useful for in vivo and in vitro studies, the limited number of isolated MNs that could be obtained from them makes it difficult to perform biochemical, genetic and pharmacological approaches. We describe here an in vitro model of isolated embryonic mouse motoneurons in which the cellular levels of endogenous SMN are reduced. These cells show neurite degeneration and cell death after several days of SMN knockdown. We found that the over-expression of the anti-apoptotic protein Bcl-x(L) into motoneurons rescues these cells from the phenotypic changes observed. This result demonstrates that Bcl-x(L) signaling could be a possible pharmacological target of SMA therapeutics.
authors.affiliation: Unitat de Senyalització Neuronal, Departament de Ciències Mèdiques Bàsiques, Universitat de Lleida-IRBLLEIDA, Montserrat Roig, 2. 25008-Lleida, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Garcera
authors.forename: Stefka
authors.initials: S
authors.lastname: Mincheva
authors.forename: Myriam
authors.initials: M
authors.lastname: Gou-Fabregas
authors.forename: Víctor
authors.initials: V
authors.lastname: Caraballo-Miralles
authors.forename: Jerònia
authors.initials: J
authors.lastname: Lladó
authors.forename: Joan X
authors.initials: JX
authors.lastname: Comella
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Soler
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D016923:Cell Death; D002478:Cells, Cultured; D004195:Disease Models, Animal; D051379:Mice; D009046:Motor Neurons / Q000378:metabolism* / Q000473:pathology; D009134:Muscular Atrophy, Spinal / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D009410:Nerve Degeneration / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D016501:Neurites / Q000378:metabolism* / Q000473:pathology; D051381:Rats; D055533:Survival of Motor Neuron 1 Protein / Q000235:genetics / Q000378:metabolism*; D051020:bcl-X Protein / Q000235:genetics / Q000378:metabolism*
chemical_list: C526472:Smn1 protein, mouse; D055533:Survival of Motor Neuron 1 Protein; D051020:bcl-X Protein