Lenzken S.C.,University of Milan Bicocca |
Romeo V.,University of Milan Bicocca |
Zolezzi F.,University of Milan Bicocca |
Cordero F.,University of Turin |
And 13 more authors.
Human Mutation | Year: 2011
Mitochondrial dysfunction has been implicated in the pathogenesis of a number of neurodegenerative disorders including Parkinson, Alzheimer, and Amyotrophic Lateral Sclerosis (ALS). In addition, aberrant mRNA splicing has been documented in neurodegeneration. To characterize the cellular response to mitochondrial perturbations at the level of gene expression and alternative pre-mRNA splicing we used splicing-sensitive microarrays to profile human neuroblastoma SH-SY5Y cells treated with paraquat, a neurotoxic herbicide that induces the formation of reactive oxygen species and causes mitochondrial damage in animal models, and SH-SY5Y cells stably expressing the mutant G93A-SOD1 protein, one of the genetic causes of ALS. In both models we identified a common set of genes whose expression and alternative splicing are deregulated. Pathway analysis of the deregulated genes revealed enrichment in genes involved in neuritogenesis, axon growth and guidance, and synaptogenesis. Alterations in transcription and pre-mRNA splicing of candidate genes were confirmed experimentally in the cell line models as well as in brain and spinal cord of transgenic mice carrying the G93A-SOD1 mutation. Our findings expand the realm of the pathways implicated in neurodegeneration and suggest that alterations of axonal function may descend directly from mitochondrial damage. © 2011 Wiley-Liss, Inc. Source
Vozzi D.,Institute for Maternal and Child Health |
Licastro D.,CBM scrl Genomics |
Martelossi S.,Institute for Maternal and Child Health |
Athanasakis E.,Institute for Maternal and Child Health |
And 2 more authors.
Molecular Syndromology | Year: 2013
Alagille syndrome (ALGS, MIM 118450) is an autosomal dominant, multisystem disorder with high variability. Two genes have been described: JAG1 and NOTCH2. The population prevalence is 1:70,000 based on the presence of neonatal liver disease. The majority of cases (∼97%) are caused by haploinsufficiency of the JAG1 gene on 20p11.2p12, either due to mutations or deletions at the locus. Less than 1% of cases are caused by mutations in NOTCH2. The most widely used methods for mutational screening include denaturing high-performance liquid chromatography (DHPLC) and multiplex ligation-dependent probe amplification (MLPA). Very recently, whole-exome sequencing (WES) has become technically feasible due to the recent advances in next-generation sequencing technologies, therefore offering new opportunities for mutations/genes identification. A proband and its family, negative for the presence of mutations in JAG1 and NOTCH2 genes by neither DHPLC nor MLPA, were analyzed by WES. A missense mutation, not previously described, in JAG1 gene was identified. This result shows an improvement in the mutation detection rate due to novel sequencing technology suggesting the strong need to reanalyze all negative cases. Copyright © 2013 S. Karger AG, Basel. Source
Vozzi D.,University of Trieste |
Aaspollu A.,Asper Biotech |
Athanasakis E.,University of Trieste |
Berto A.,University of Ferrara |
And 11 more authors.
Molecular Vision | Year: 2011
Purpose: Usher syndrome is an autosomal recessive disorder characterized by hearing and vision loss. Usher syndrome is divided into three clinical subclasses (type 1, type 2, and type 3), which differ in terms of the severity and progression of hearing loss and the presence or absence of vestibular symptoms. Usher syndrome is defined by significant genetic heterogeneity, with at least 12 distinct loci described and 9 genes identified. This study aims to provide a molecular epidemiology report of Usher syndrome in Italy. Methods: Molecular data have been obtained on 75 unrelated Italian patients using the most up-to date technology available for the screening of Usher syndrome gene mutations, i.e., the genotyping microarray developed by Asper Biotech (Tartu, Estonia), which simultaneously investigates 612 different marker positions using the well established arrayed primer extension methodology (APEX). Results: Using this method, we found that 12% of cases (9 out of 75) harbored homozygous or compound heterozygous mutations in the gene positions analyzed, whereas 20% (15 out of 75) of the patients were characterized by the presence of only one mutated allele based on the positions analyzed. One patient was found to be compound heterozygous for mutations in two different genes and this represents an example of possible digenic inheritance in Usher syndrome. A total of 66.6% of cases (50 out of 75) were found to be completely negative for the presence of Usher syndrome gene mutations in the detected positions. Mutations detected by the array were confirmed by direct sequencing. Conclusions: These findings highlight the efficacy of the APEX-based genotyping approach in the molecular assessment of Usher patients, suggesting the presence of alleles not yet identified and/or the involvement of additional putative genes that may account for the pathogenesis of Usher syndrome. © 2011 Molecular Vision. Source
Cantoni C.,University of Washington |
Bollman B.,University of Washington |
Licastro D.,CBM scrl Genomics |
Xie M.,University of Washington |
And 9 more authors.
Acta Neuropathologica | Year: 2015
Microglia are phagocytic cells that survey the brain and perform neuroprotective functions in response to tissue damage, but their activating receptors are largely unknown. Triggering receptor expressed on myeloid cells 2 (TREM2) is a microglial immunoreceptor whose loss-of-function mutations in humans cause presenile dementia, while genetic variants are associated with increased risk of neurodegenerative diseases. In myeloid cells, TREM2 has been involved in the regulation of phagocytosis, cell proliferation and inflammatory responses in vitro. However, it is unknown how TREM2 contributes to microglia function in vivo. Here, we identify a critical role for TREM2 in the activation and function of microglia during cuprizone (CPZ)-induced demyelination. TREM2-deficient (TREM2−/−) mice had defective clearance of myelin debris and more axonal pathology, resulting in impaired clinical performances compared to wild-type (WT) mice. TREM2−/− microglia proliferated less in areas of demyelination and were less activated, displaying a more resting morphology and decreased expression of the activation markers MHC II and inducible nitric oxide synthase as compared to WT. Mechanistically, gene expression and ultrastructural analysis of microglia suggested a defect in myelin degradation and phagosome processing during CPZ intoxication in TREM2−/− microglia. These findings place TREM2 as a key regulator of microglia activation in vivo in response to tissue damage. © 2015, Springer-Verlag Berlin Heidelberg. Source
Yang L.,Harvard University |
Licastro D.,CBM scrl Genomics |
Cava E.,University of Rome La Sapienza |
Veronese N.,University of Padua |
And 7 more authors.
Cell Reports | Year: 2015
Calorie restriction (CR) retards aging, acts as a hormetic intervention, and increases serum corticosterone and HSP70 expression in rodents. However, less is known regarding the effects of CR on these factors in humans. Serum cortisol and molecular chaperones and autophagic proteins were measured in the skeletal muscle of subjects on CR diets for 3-15 years and in control volunteers. Serum cortisol was higher in the CR group than in age-matched sedentary and endurance athlete groups (15.6 ± 4.6 ng/dl versus 12.3 ± 3.9 ng/dl and 11.2 ± 2.7 ng/dl, respectively; p ≤ 0.001). HSP70, Grp78, beclin-1, and LC3 mRNA and/or protein levels were higher in the skeletal muscle of the CR group compared to controls. Our data indicate that CR in humans is associated with sustained rises in serum cortisol, reduced inflammation, and increases in key molecular chaperones and autophagic mediators involved in cellular protein quality control and removal of dysfunctional proteins and organelles. Yang et al. show that calorie restriction without malnutrition in humans inhibits inflammation, at least in part by elevating serum cortisol concentration, and increases chaperone and autophagy genes and proteins involved in protein quality control and organelle homeostasis in the removal of dysfunctional proteins and organelles from cell. © 2016 The Authors. Source