43 research outputs found
Evaluation of pet animals involved in assisted interventions (AAI) as potential carriers of bacteria resistant to antimicrobials: Preliminary data
open8noopenDotto, G.; Pasotto, D.; Poser, H.; Menandro, M.L.; Berlanda, M.; Falomo, M.E.; Mondin, A.; Martini, M.Dotto, Giorgia; Pasotto, Daniela; Poser, Helen; Menandro, MARIA LUISA; Berlanda, Michele; Falomo, MARIA ELENA; Mondin, Alessandra; Martini, Marc
Sorcin is an early marker of neurodegeneration, Ca2+ dysregulation and endoplasmic reticulum stress associated to neurodegenerative diseases
Dysregulation of calcium signaling is emerging as a key feature in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD), and targeting this process may be therapeutically beneficial. Under this perspective, it is important to study proteins that regulate calcium homeostasis in the cell. Sorcin is one of the most expressed calcium-binding proteins in the human brain; its overexpression increases endoplasmic reticulum (ER) calcium concentration and decreases ER stress in the heart and in other cellular types. Sorcin has been hypothesized to be involved in neurodegenerative diseases, since it may counteract the increased cytosolic calcium levels associated with neurodegeneration. In the present work, we show that Sorcin expression levels are strongly increased in cellular, animal, and human models of AD, PD, and HD, vs. normal cells. Sorcin partially colocalizes with RyRs in neurons and microglia cells; functional experiments with microsomes containing high amounts of RyR2 and RyR3, respectively, show that Sorcin is able to regulate these ER calcium channels. The molecular basis of the interaction of Sorcin with RyR2 and RyR3 is demonstrated by SPR. Sorcin also interacts with other ER proteins as SERCA2 and Sigma-1 receptor in a calcium-dependent fashion. We also show that Sorcin regulates ER calcium transients: Sorcin increases the velocity of ER calcium uptake (increasing SERCA activity). The data presented here demonstrate that Sorcin may represent both a novel early marker of neurodegenerative diseases and a response to cellular stress dependent on neurodegeneration
DRB1*03:01 Haplotypes: Differential Contribution to Multiple Sclerosis Risk and Specific Association with the Presence of Intrathecal IgM Bands
BACKGROUND: Multiple sclerosis (MS) is a multifactorial disease with a genetic basis. The strongest associations with the disease lie in the Human Leukocyte Antigen (HLA) region. However, except for the DRB1*15:01 allele, the main risk factor associated to MS so far, no consistent effect has been described for any other variant. One example is HLA-DRB1*03:01, with a heterogeneous effect across populations and studies. We postulate that those discrepancies could be due to differences in the diverse haplotypes bearing that allele. Thus, we aimed at studying the association of DRB1*03:01 with MS susceptibility considering this allele globally and stratified by haplotypes. We also evaluated the association with the presence of oligoclonal IgM bands against myelin lipids (OCMB) in cerebrospinal fluid. METHODS: Genotyping of HLA-B, -DRB1 and -DQA1 was performed in 1068 MS patients and 624 ethnically matched healthy controls. One hundred and thirty-nine MS patients were classified according to the presence (M+, 58 patients)/absence (M-, 81 patients) of OCMB. Comparisons between groups (MS patients vs. controls and M+ vs. M-) were performed with the chi-square test or the Fisher exact test. RESULTS: Association of DRB1*03:01 with MS susceptibility was observed but with different haplotypic contribution, being the ancestral haplotype (AH) 18.2 the one causing the highest risk. Comparisons between M+, M- and controls showed that the AH 18.2 was affecting only M+ individuals, conferring a risk similar to that caused by DRB1*15:01. CONCLUSIONS: The diverse DRB1*03:01-containing haplotypes contribute with different risk to MS susceptibility. The AH 18.2 causes the highest risk and affects only to individuals showing OCMB
The isolated carboxy-terminal domain of human mitochondrial leucyl-tRNA synthetase rescues the pathological phenotype of mitochondrial tRNA mutations in human cells.
Mitochondrial (mt) diseases are multisystem disorders due to mutations in nuclear or mtDNA genes. Among the latter, more than 50% are located in transfer RNA (tRNA) genes and are responsible for a wide range of syndromes, for which no effective treatment is available at present. We show that three human mt aminoacyl-tRNA syntethases, namely leucyl-, valyl-, and isoleucyl-tRNA synthetase are able to improve both viability and bioenergetic proficiency of human transmitochondrial cybrid cells carrying pathogenic mutations in the mt-tRNA(Ile) gene. Importantly, we further demonstrate that the carboxy-terminal domain of human mt leucyl-tRNA synthetase is both necessary and sufficient to improve the pathologic phenotype associated either with these "mild" mutations or with the "severe" m.3243A>G mutation in the mt-tRNA(L)(eu(UUR)) gene. Furthermore, we provide evidence that this small, non-catalytic domain is able to directly and specifically interact in vitro with human mt-tRNA(Leu(UUR)) with high affinity and stability and, with lower affinity, with mt-tRNA(Ile). Taken together, our results sustain the hypothesis that the carboxy-terminal domain of human mt leucyl-tRNA synthetase can be used to correct mt dysfunctions caused by mt-tRNA mutations
CD40: Novel Association with Crohn's Disease and Replication in Multiple Sclerosis Susceptibility
Background: A functional polymorphism located at 21 from the start codon of the CD40 gene, rs1883832, was previously
reported to disrupt a Kozak sequence essential for translation. It has been consistently associated with Graves’ disease risk in
populations of different ethnicity and genetic proxies of this variant evaluated in genome-wide association studies have
shown evidence of an effect in rheumatoid arthritis and multiple sclerosis (MS) susceptibility. However, the protective allele
associated with Graves’ disease or rheumatoid arthritis has shown a risk role in MS, an effect that we aimed to replicate in
the present work. We hypothesized that this functional polymorphism might also show an association with other complex
autoimmune condition such as inflammatory bowel disease, given the CD40 overexpression previously observed in Crohn’s
disease (CD) lesions.
Methodology: Genotyping of rs1883832C.T was performed in 1564 MS, 1102 CD and 969 ulcerative colitis (UC) Spanish
patients and in 2948 ethnically matched controls by TaqMan chemistry.
Principal Findings: The observed effect of the minor allele rs1883832T was replicated in our independent Spanish MS
cohort [p= 0.025; OR (95% CI)= 1.12 (1.01–1.23)]. The frequency of the minor allele was also significantly higher in CD
patients than in controls [p= 0.002; OR (95% CI)= 1.19 (1.06–1.33)]. This increased predisposition was not detected in UC
patients [p= 0.5; OR (95% CI)= 1.04 (0.93–1.17)].
Conclusion: The impact of CD40 rs1883832 on MS and CD risk points to a common signaling shared by these autoimmune
conditions.Peer reviewe
Genome-Wide Association Study of Multiple Sclerosis Confirms a Novel Locus at 5p13.1
Multiple Sclerosis (MS) is the most common progressive and disabling neurological condition affecting young adults in the world today. From a genetic point of view, MS is a complex disorder resulting from the combination of genetic and non-genetic factors. We aimed to identify previously unidentified loci conducting a new GWAS of Multiple Sclerosis (MS) in a sample of 296 MS cases and 801 controls from the Spanish population. Meta-analysis of our data in combination with previous GWAS was done. A total of 17 GWAS-significant SNPs, corresponding to three different loci were identified:HLA, IL2RA, and 5p13.1. All three have been previously reported as GWAS-significant. We confirmed our observation in 5p13.1 for rs9292777 using two additional independent Spanish samples to make a total of 4912 MS cases and 7498 controls (ORpooled = 0.84; 95%CI: 0.80–0.89; p = 1.36×10-9). This SNP differs from the one reported within this locus in a recent GWAS. Although it is unclear whether both signals are tapping the same genetic association, it seems clear that this locus plays an important role in the pathogenesis of MS
Early B-cell Factor gene association with multiple sclerosis in the Spanish population
BACKGROUND: The etiology of multiple sclerosis (MS) is at present not fully elucidated, although it is considered to result from the interaction of environmental and genetic susceptibility factors. In this work we aimed at testing the Early B-cell Factor (EBF1) gene as a functional and positional candidate risk factor for this neurological disease. Axonal damage is a hallmark for multiple sclerosis clinical disability and EBF plays an evolutionarily conserved role in the expression of proteins essential for axonal pathfinding. Failure of B-cell differentiation was found in EBF-deficient mice and involvement of B-lymphocytes in MS has been suggested from their presence in cerebrospinal fluid and lesions of patients. METHODS: The role of the EBF1 gene in multiple sclerosis susceptibility was analyzed by performing a case-control study with 356 multiple sclerosis patients and 540 ethnically matched controls comparing the EBF1 polymorphism rs1368297 and the microsatellite D5S2038. RESULTS: Significant association of an EBF1-intronic polymorphism (rs1368297, A vs. T: p = 0.02; OR = 1.26 and AA vs. [TA+TT]: p = 0.02; OR = 1.39) was discovered. This association was even stronger after stratification for the well-established risk factor of multiple sclerosis in the Major Histocompatibility Complex, DRB1*1501 (AA vs. [TA+TT]: p = 0.005; OR = 1.78). A trend for association in the case-control study of another EBF1 marker, the allele 5 of the very informative microsatellite D5S2038, was corroborated by Transmission Disequilibrium Test of 53 trios (p = 0.03). CONCLUSION: Our data support EBF1 gene association with MS pathogenesis in the Spanish white population. Two genetic markers within the EBF1 gene have been found associated with this neurological disease, indicative either of their causative role or that of some other polymorphism in linkage disequilibrium with them
A PP2A-B55 recognition signal controls substrate dephosphorylation kinetics during mitotic exit
Unravelling sorcin mechanism of action in multi drug resistance tumor cells
Sorcin is a calcium binding protein, mainly known for its role in muscle contraction, where it participates in the termination of the contraction and in the onset of relaxation by modulating calcium channels at the endo/sarcoplamic reticulum (Ryanodine Receptor and SERCA pump) and at the plasma membrane (Na+/Ca2+ exchanger). Since few years ago, sorcin has started to be reported as overexpressed in several different multi drug resistant tumors but little was known about its network of interaction and its behavior in the cell in different stages of the cell cycle. Sorcin overexpression and silencing alter cell morphology and cell fate and protein modifications (mainly phosphorylations) affect sorcin functions. Moreover sorcin binds directly chemotherapics (doxorubicin in particular) giving a partial explanation for the manifestation of Multi Drug Resistance in tumor cells. Sorcin is also abundant in the brain and the neuroblastoma cell line Sh-Sy5y treated with compounds mimicking stimuli that induce neurodegenative manifestations shows even an increased level of expression of sorcin raising the hypothesis that sorcin might be involved in mechanisms linked to neurodegenerative disorders
Surface plasmon resonance: a useful strategy for the identification of small molecule argonaute 2 protein binders
Surface plasmon resonance (SPR) is one of the most important techniques for the detection and the characterization of molecular interactions. SPR technology is a label-free approach for monitoring biomolecular interactions in real time. The binding of analytes to molecules immobilized on a thin metal film (ligand) determines a change in the refractive index and, therefore in the angle of extinction of light, is reflected when polarized light hits the film, monitored in real time as a change in the position of the dip in reflected intensity. Since SPR detects mass, the technique is label-free. Here, we describe the use of SPR techniques to study the interaction between Argonaute 2 and small molecular compounds selected by means of high-throughput docking screening