Dataset Information

Biochemical effects of mutations in the gene encoding the alpha subunit of eukaryotic initiation factor (eIF) 2B associated with Vanishing White Matter disease.

ABSTRACT: Leukoencephalopathy with Vanishing White Matter (VWM) is an autosomal recessive disorder caused by germline mutations in the genes EIF2B1-5, which encode the 5 subunits of the eukaryotic translation initiation factor eIF2B. To date, analysis of the biochemical effects of mutations in the EIF2B2-5 genes has been carried out, but no study has been performed on mutations in the EIF2B1 gene. This gene encodes eIF2B?, the smallest subunit in eIF2B which has an important role in both the structure and regulation of the eIF2B complex.eIF2B subunits were overexpressed in HEK293 cells and isolated from the resulting cell lysates by affinity chromatography. Formation of the eIF2B complex and binding of its substrate, eIF2, was assessed by western blot. Assays of the guanine nucleotide exchange (GEF) activity were also carried out.Of the 5 eIF2B? mutations studied, we found 3 that showed loss or reduction of binding of eIF2B? to the rest of the complex, one with increased GEF activity, and one where no effects on activity or complex formation were observed.This is the first study on eIF2B? VWM mutations. We show that some mutations cause expected decreases in GEF activity or complex formation, similar to a majority of observed VWM mutations. However, we also observe some unexpected changes which hint at other effects of these mutations on as yet undescribed functions of eIF2B.

SUBMITTER: Wortham NC

PROVIDER: S-EPMC4593227 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Biochemical effects of mutations in the gene encoding the alpha subunit of eukaryotic initiation factor (eIF) 2B associated with Vanishing White Matter disease.

Wortham Noel C NC Proud Christopher G CG

BMC medical genetics 20150819

<h4>Background</h4>Leukoencephalopathy with Vanishing White Matter (VWM) is an autosomal recessive disorder caused by germline mutations in the genes EIF2B1-5, which encode the 5 subunits of the eukaryotic translation initiation factor eIF2B. To date, analysis of the biochemical effects of mutations in the EIF2B2-5 genes has been carried out, but no study has been performed on mutations in the EIF2B1 gene. This gene encodes eIF2Bα, the smallest subunit in eIF2B which has an important role in bot ...[more]

PMID: 26285592

Similar Datasets

Project description:Vanishing white matter (VWM) is a leukodystrophy caused by biallelic pathogenic variants in eukaryotic translation initiation factor 2B. Neuropathology includes lack of reactive gliosis, paucity of myelin, and axonal abnormalities. Alteration in proteins involved in cellular metabolism has also been implicated in the disease. It, however, remains unclear which factors contribute to VWM pathogenesis. Here, we aimed at gaining insight into the basis of VWM pathogenesis using the 2b5ho mouse model of VWM. We first investigated the temporal proteome in the cerebellum, corpus callosum, cortex, and brainstem of 2b5ho and wild type (WT) mice. Protein changes observed in 2b5ho mice were then cross-referenced with published proteomic datasets from post mortem VWM patient brain tissue to define alterations relevant to the human disease. By comparing 2b5ho mice with their region- and age-matched WT counterparts, we identified region-specific protein changes associated with disease development and progression. We showed that the proteome in the cerebellum and cortex of 2b5ho mice was already deregulated prior to pathology development, whereas proteome changes in the corpus callosum only occurred after onset of pathology. Remarkably, protein changes in the brainstem were transient, indicating that a compensatory mechanism might occur in this region throughout the disease course. Gene ontology overrepresentation analysis revealed that proteome changes observed in 2b5ho mouse brains reflect alterations in features well-known in VWM. Side-by-side comparison of the 2b5ho mouse and VWM patient brain proteomes revealed that part of protein changes were the same as in VWM patients. These could represent relevant changes that contribute to the disease or even drive its progression in VWM patients. Taken together, we show that the proteome in the brain of 2b5ho mice is affected in a region-specific and time-dependent manner. We found that the 2b5ho mouse model partly replicates the human disease at the protein level, and provides a spatiotemporal proteome resource to study aspects of VWM pathogenesis. This resource highlights alterations presenting from early to late disease stages, and those that possibly drive disease progression.

Dataset Information

Biochemical effects of mutations in the gene encoding the alpha subunit of eukaryotic initiation factor (eIF) 2B associated with Vanishing White Matter disease.

Publications

Biochemical effects of mutations in the gene encoding the alpha subunit of eukaryotic initiation factor (eIF) 2B associated with Vanishing White Matter disease.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure