831 research outputs found

    The Emergence of Alternative 3′ and 5′ Splice Site Exons from Constitutive Exons

    Get PDF
    Alternative 3′ and 5′ splice site (ss) events constitute a significant part of all alternative splicing events. These events were also found to be related to several aberrant splicing diseases. However, only few of the characteristics that distinguish these events from alternative cassette exons are known currently. In this study, we compared the characteristics of constitutive exons, alternative cassette exons, and alternative 3′ss and 5′ss exons. The results revealed that alternative 3′ss and 5′ss exons are an intermediate state between constitutive and alternative cassette exons, where the constitutive side resembles constitutive exons, and the alternative side resembles alternative cassette exons. The results also show that alternative 3′ss and 5′ss exons exhibit low levels of symmetry (frame-preserving), similar to constitutive exons, whereas the sequence between the two alternative splice sites shows high symmetry levels, similar to alternative cassette exons. In addition, flanking intronic conservation analysis revealed that exons whose alternative splice sites are at least nine nucleotides apart show a high conservation level, indicating intronic participation in the regulation of their splicing, whereas exons whose alternative splice sites are fewer than nine nucleotides apart show a low conservation level. Further examination of these exons, spanning seven vertebrate species, suggests an evolutionary model in which the alternative state is a derivative of an ancestral constitutive exon, where a mutation inside the exon or along the flanking intron resulted in the creation of a new splice site that competes with the original one, leading to alternative splice site selection. This model was validated experimentally on four exons, showing that they indeed originated from constitutive exons that acquired a new competing splice site during evolution

    RNA-editing-mediated exon evolution

    Get PDF
    BACKGROUND: Alu retroelements are specific to primates and abundant in the human genome. Through mutations that create functional splice sites within intronic Alus, these elements can become new exons in a process denoted exonization. It was recently shown that Alu elements are also heavily changed by RNA editing in the human genome. RESULTS: Here we show that the human nuclear prelamin A recognition factor contains a primate-specific Alu-exon that exclusively depends on RNA editing for its exonization. We demonstrate that RNA editing regulates the exonization in a tissue-dependent manner, through both the creation of a functional AG 3' splice site, and alteration of functional exonic splicing enhancers within the exon. Furthermore, a premature stop codon within the Alu-exon is eliminated by an exceptionally efficient RNA editing event. The sequence surrounding this editing site is important not only for editing of that site but also for editing in other neighboring sites as well. CONCLUSION: Our results show that the abundant RNA editing of Alu sequences can be recruited as a mechanism supporting the birth of new exons in the human genome

    MTADV 5-MER peptide suppresses chronic inflammations as well as autoimmune pathologies and unveils a new potential target-Serum Amyloid A.

    Get PDF
    Despite the existence of potent anti-inflammatory biological drugs e.g., anti-TNF and anti IL-6 receptor antibodies, for treating chronic inflammatory and autoimmune diseases, these are costly and not specific. Cheaper oral available drugs remain an unmet need. Expression of the acute phase protein Serum Amyloid A (SAA) is dependent on release of pro-inflammatory cytokines IL-1, IL-6 and TNF-α during inflammation. Conversely, SAA induces pro-inflammatory cytokine secretion, including Th17, leading to a pathogenic vicious cycle and chronic inflammation. 5- MER peptide (5-MP) MTADV (methionine-threonine-alanine-aspartic acid-valine), also called Amilo-5MER, was originally derived from a sequence of a pro-inflammatory CD44 variant isolated from synovial fluid of a Rheumatoid Arthritis (RA) patient. This human peptide displays an efficient anti-inflammatory effects to ameliorate pathology and clinical symptoms in mouse models of RA, Inflammatory Bowel Disease (IBD) and Multiple Sclerosis (MS). Bioinformatics and qRT-PCR revealed that 5-MP, administrated to encephalomyelytic mice, up-regulates genes contributing to chronic inflammation resistance. Mass spectrometry of proteins that were pulled down from an RA synovial cell extract with biotinylated 5-MP, showed that it binds SAA. 5-MP disrupted SAA assembly, which is correlated with its pro-inflammatory activity. The peptide MTADV (but not scrambled TMVAD) significantly inhibited the release of pro-inflammatory cytokines IL-6 and IL-1β from SAA-activated human fibroblasts, THP-1 monocytes and peripheral blood mononuclear cells. 5-MP suppresses the pro-inflammatory IL-6 release from SAA-activated cells, but not from non-activated cells. 5-MP could not display therapeutic activity in rats, which are SAA deficient, but does inhibit inflammations in animal models of IBD and MS, both are SAA-dependent, as shown by others in SAA knockout mice. In conclusion, 5-MP suppresses chronic inflammation in animal models of RA, IBD and MS, which are SAA-dependent, but not in animal models, which are SAA-independent

    External applicability of the Effect of ticagrelor on Health Outcomes in diabEtes Mellitus patients Intervention Study (THEMIS) trial: An analysis of patients with diabetes and coronary artery disease in the REduction of Atherothrombosis for Continued Health (REACH) registry.

    Get PDF
    THEMIS is a double-blind, randomized trial of 19,220 patients with diabetes mellitus and stable coronary artery disease (CAD) comparing ticagrelor to placebo, in addition to aspirin. The present study aimed to describe the proportion of patients eligible and reasons for ineligibility for THEMIS within a population of patients with diabetes and CAD included in the Reduction of Atherothrombosis for Continued Health (REACH) registry. The THEMIS eligibility criteria were applied to REACH patients. THEMIS included patients ≥50 years with type 2 diabetes and stable CAD as determined by either a history of previous percutaneous coronary intervention, coronary artery bypass grafting, or documentation of angiographic stenosis of ≥50% of at least one coronary artery. Patients with prior myocardial infarction or stroke were excluded. In REACH, 10,156 patients had stable CAD and diabetes. Of these, 6515 (64.1%) patients had at least one exclusion criteria. From the remaining population, 784 patients did not meet inclusion criteria (7.7%) mainly due to absence of aspirin treatment (7.2%), yielding a 'THEMIS-eligible population' of 2857 patients (28.1% of patients with diabetes and stable CAD). The main reasons for exclusion were a history of myocardial infarction (53.1%), use of oral anticoagulation (14.5%), or history of stroke (12.9%). Among the 4208 patients with diabetes and a previous PCI, 1196 patients (28.4%) were eligible for inclusion in the THEMIS-PCI substudy. In a population of patients with diabetes and stable coronary artery disease, a sizeable proportion appear to be 'THEMIS eligible.' http://www. gov identifier: NCT01991795.The THEMIS trial was funded by AstraZeneca. The REACH registry was sponsored by Sanofi, Bristol-Myers Squibb, and the Waksman Foundation (Tokyo, Japan) and is endorsed by the World Heart Federation.S

    Eukaryotic Initiation Factor 4E (eIF4E) and angiogenesis: prognostic markers for breast cancer

    Get PDF
    BACKGROUND: The overexpression of eukaryotic translation initiation factor 4E (eIF4E), a key regulator of protein synthesis, is involved in the malignant progression of human breast cancer. This study investigates the relationship between eIF4E and angiogenesis, as well as their prognostic impact in patients with human breast cancer. METHODS: Immunohistochemical staining was used to determine protein expression of eIF4E, vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), and CD105 in a set of 122 formalin-fixed, paraffin-embedded primary breast cancer tissues. Expression of eIF4E in positive cells was characterized by cytoplasmic staining. Evaluation of VEGF and IL-8 in the same tissue established the angiogenic profiles, while CD105 was used as an indicator of microvessel density (MVD). RESULTS: A significant relationship was found between the level of eIF4E expression and histological grade (P = 0.016). VEGF, IL-8, and MVD were closely related to tumor grade (P = 0.003, P = 0.022, and P < 0.001, respectively) and clinical stage (P = 0.007, P = 0.048, and P < 0.001, respectively). Expression of eIF4E was also significantly correlated with VEGF (P = 0.007), IL-8 (P = 0.007), and MVD (P = 0.006). Patients overexpressing eIF4E had significantly worse overall (P = 0.01) and disease-free survival (P = 0.006). When eIF4E, histological grade, tumor stage, ER, PR, Her-2 status and the levels of VEGF, IL-8, MVD were included in a multivariate Cox regression analysis, eIF4E emerged as an independent prognostic factor for breast cancer (P = 0.001), along with stage (P = 0.005), node status (P = 0.046), and MVD (P = 0.004). CONCLUSION: These results suggest that higher eIF4E expression correlates with both angiogenesis and vascular invasion of cancer cells, and could therefore serve as a useful histological predictor for less favorable outcome in breast cancer patients, as well as represent a potential therapeutic target

    Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

    Get PDF
    The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of ttt\overline{t}, W+bbW+b\overline{b} and W+ccW+c\overline{c} is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 ±\pm 0.02 \mbox{fb}^{-1}. The WW bosons are reconstructed in the decays WνW\rightarrow\ell\nu, where \ell denotes muon or electron, while the bb and cc quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

    Guidelines for acute ischemic stroke treatment: part I

    Full text link
    corecore