RESUMO
Alterations of Ca2+ homeostasis have been implicated in a wide range of neurodegenerative diseases. Ca2+ efflux from the endoplasmic reticulum into the cytoplasm is controlled by binding of inositol 1,4,5-trisphosphate to its receptor. Activated inositol 1,4,5-trisphosphate receptors are then rapidly degraded by the endoplasmic reticulum-associated degradation pathway. Mutations in genes encoding the neuronal isoform of the inositol 1,4,5-trisphosphate receptor (ITPR1) and genes involved in inositol 1,4,5-trisphosphate receptor degradation (ERLIN1, ERLIN2) are known to cause hereditary spastic paraplegia (HSP) and cerebellar ataxia. We provide evidence that mutations in the ubiquitin E3 ligase gene RNF170, which targets inositol 1,4,5-trisphosphate receptors for degradation, are the likely cause of autosomal recessive HSP in four unrelated families and functionally evaluate the consequences of mutations in patient fibroblasts, mutant SH-SY5Y cells and by gene knockdown in zebrafish. Our findings highlight inositol 1,4,5-trisphosphate signaling as a candidate key pathway for hereditary spastic paraplegias and cerebellar ataxias and thus prioritize this pathway for therapeutic interventions.
Assuntos
Degradação Associada com o Retículo Endoplasmático/genética , Fibroblastos/metabolismo , Neurônios/metabolismo , Paraplegia Espástica Hereditária/genética , Ubiquitina-Proteína Ligases/genética , Adolescente , Adulto , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Criança , Pré-Escolar , Retículo Endoplasmático/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Transdução de Sinais , Pele/citologia , Paraplegia Espástica Hereditária/metabolismo , Peixe-ZebraRESUMO
Gaucher disease is the most common autosomal recessive lysosomal storage disorder, caused by mutations in the ß-glucocerebrosidase gene GBA. Here we describe generation of iPSC from skin-derived fibroblasts from two unrelated individuals with neuronopathic forms of Gaucher disease. The donor for line iPSC-GBA-1, a 21â¯month old girl, carried the recurring GBA mutation c.1448â¯Tâ¯>â¯C, p.Leu483Pro at homozygous state; fibroblasts for line iPS-GBA-2 were obtained from a 4â¯year old girl compound heterozygous for the GBA mutations c.667â¯Tâ¯>â¯C, p.Trp223Arg and c.1226Aâ¯>â¯G, p.Asn409Ser. iPSCs were developed using integration free episomal vectors (OCT4, KLF4; L-MYC, SOX2 (OSKM) and LIN28). Resource table.
