Lifestyle and Horizontal Gene Transfer- Mediated Evolution of \u3ci\u3eMucispirillum schaedleri\u3c/i\u3e, a Core Member of the Murine Gut Microbiota

Mucispirillum schaedleri is an abundant inhabitant of the intestinal mucus layer of rodents and other animals and has been suggested to be a pathobiont, a commensal that plays a role in disease. In order to gain insights into its lifestyle, we analyzed the genome and transcriptome of M. schaedleri ASF 457 and performed physiological experiments to test traits predicted by its genome. Although described as a mucus inhabitant, M. schaedleri has limited capacity for degrading host-derived mucosal glycans and other complex polysaccharides. Additionally, M. schaedleri reduces nitrate and expresses systems for scavenging oxygen and reactive oxygen species in vivo, which may account for its localization close to the mucosal tissue and expansion during inflammation. Also of note, M. schaedleri harbors a type VI secretion system and putative effector proteins and can modify gene expression in mucosal tissue, suggesting intimate interactions with its host and a possible role in inflammation. The M. schaedleri genome has been shaped by extensive horizontal gene transfer, primarily from intestinal Epsilon- and Deltaproteobacteria, indicating that horizontal gene transfer has played a key role in defining its niche in the gut ecosystem

Lifestyle and Horizontal Gene Transfer- Mediated Evolution of Mucispirillum schaedleri, a Core Member of the Murine Gut Microbiota

Mucispirillum schaedleri is an abundant inhabitant of the intestinal mucus layer of rodents and other animals and has been suggested to be a pathobiont, a commensal that plays a role in disease. In order to gain insights into its lifestyle, we analyzed the genome and transcriptome of M. schaedleri ASF 457 and performed physiological experiments to test traits predicted by its genome. Although described as a mucus inhabitant, M. schaedleri has limited capacity for degrading host-derived mucosal glycans and other complex polysaccharides. Additionally, M. schaedleri reduces nitrate and expresses systems for scavenging oxygen and reactive oxygen species in vivo, which may account for its localization close to the mucosal tissue and expansion during inflammation. Also of note, M. schaedleri harbors a type VI secretion system and putative effector proteins and can modify gene expression in mucosal tissue, suggesting intimate interactions with its host and a possible role in inflammation. The M. schaedleri genome has been shaped by extensive horizontal gene transfer, primarily from intestinal Epsilon- and Deltaproteobacteria, indicating that horizontal gene transfer has played a key role in defining its niche in the gut ecosystem

Nouvelles données sur la séquence aurignacienne de la grotte d'Isturitz (communes d'Isturitz et de Saint-Martin-d'Arberoue. Pyrénées-Atlantiques)

Isturitz Cave is located in the western Pyrenees in the heart of the zone of passage and contact between the Aquitaine region and the Vasco-Cantabrian ledge. Excavations during the first half of the 20th century yielded a remarkable archaeological sequence covering the Middle Palaeolithic and the entire Upper Palaeolithic. New research conducted in the Saint-Martin chamber has revealed intensive Aurignacian occupations attributed to the archaic and early phases of this techno-complex. In this paper, we present a synthesis of the principal data that make Isturitz a key site in the study of this period.Située dans les Pyrénées occidentales, au coeur de la zone de passage et de contact entre l'Aquitaine et la corniche vasco-cantabrique, la grotte d'Isturitz a fait l'objet, dans la première moitié du XXe siècle, de fouilles qui ont livré un remarquable ensemble archéologique couvrant le Paléolithique moyen et la quasi-totalité du Paléolithique supérieur. De nouvelles recherches menées dans la salle de Saint-Martin ont mis en évidence d'importantes occupations aurignaciennes attribuées aux phases archaïques et anciennes de ce technocomplexe. Nous ferons dans cet article une synthèse des principales données qui font de la grotte d'Isturitz un site clef pour l'étude de celles-ci

Upstream ORF affects MYCN translation depending on exon 1b alternative splicing

<p>Abstract</p> <p>Background</p> <p>The <it>MYCN </it>gene is transcribed into two major mRNAs: one full-length (<it>MYCN) </it>and one exon 1b-spliced (<it>MYCN</it>^{Δ1<it>b</it>}) mRNA. But nothing is known about their respective ability to translate the MYCN protein.</p> <p>Methods</p> <p>Plasmids were prepared to enable translation from the upstream (uORF) and major ORF of the two <it>MYCN </it>transcripts. Translation was studied after transfection in neuroblastoma SH-EP cell line. Impact of the upstream AUG on translation was evaluated after directed mutagenesis. Functional study with the two <it>MYCN </it>mRNAs was conducted by a cell viability assay. Existence of a new protein encoded by the <it>MYCN</it>^{Δ1<it>b </it>}uORF was explored by designing a rabbit polyclonal antibody against a specific epitope of this protein.</p> <p>Results</p> <p>Both are translated, but higher levels of protein were seen with <it>MYCN</it>^{Δ1<it>b </it>}mRNA. An upstream ORF was shown to have positive cis-regulatory activity on translation from <it>MYCN </it>but not from <it>MYCN</it>^{Δ1<it>b </it>}mRNA. In transfected SH-EP neuroblastoma cells, high MYCN dosage obtained with <it>MYCN</it>^{Δ1<it>b </it>}mRNA translation induces an antiapoptotic effect after serum deprivation that was not observed with low MYCN expression obtained with <it>MYCN </it>mRNA. Here, we showed that MYCNOT: <it>MYCN </it>Overlap Transcript, a new protein of unknown function is translated from the upstream AUG of <it>MYCN</it>^{Δ1<it>b </it>}mRNA.</p> <p>Conclusions</p> <p>Existence of upstream ORF in <it>MYCN </it>transcripts leads to a new level of MYCN regulation. The resulting MYCN dosage has a weak but significant anti-apoptotic activity after intrinsic apoptosis induction.</p

Isatuximab plus carfilzomib and dexamethasone in patients with early <i>versus</i> late relapsed multiple myeloma: IKEMA subgroup analysis

Patients with multiple myeloma (MM) who experience early relapse within 12 months of therapy initiation are considered functional high-risk and represent an unmet need, needing better therapies to improve outcomes. The final IKEMA (clinicaltrials gov. identifier: NCT03275285) progression-free survival (PFS) analysis confirmed the significant PFS improvement reported at interim analysis with isatuximab (Isa) plus carfilzomib and dexamethasone (Kd; Isa-Kd) versus Kd in patients with relapsed MM (updated median PFS: 35.7 vs. 19.2 months; hazard ratio [HR] =0.58, 95% confidence interval [CI]: 0.42- 0.79). This IKEMA subgroup analysis examined efficacy and safety of Isa-Kd versus Kd in patients who experienced early (n=61 [Isa-Kd], n=46 [Kd]) vs. late relapse (n=104 [Isa-Kd], n=72 [Kd]). As expected, more aggressive features in baseline characteristics were observed in early relapse patients. Consistent with IKEMA overall population results, median PFS (early relapse: 24.7 vs. 17.2 months, HR=0.662, 95% CI: 0.407-1.077; late relapse: 42.7 vs. 21.9 months, HR=0.542, 95% CI: 0.355- 0.826), minimal residual disease negativity (MRD−) (early relapse: 24.6% vs. 15.2%; late relapse: 37.5% vs. 16.7%), and MRD− complete response (≥CR) rates (early relapse: 18.0% vs. 10.9%; late relapse: 30.8% vs. 13.9%) were higher with Isa-Kd versus Kd, respectively, in both early and late relapse patients. Grade ≥3, serious treatment-emergent adverse events, and death rates were higher in the late relapse Isa-Kd arm. However, the numbers of deaths were low and treatment exposure was significantly longer in Isa-Kd versus Kd late relapse patients. These results support the addition of Isa to Kd as standardof- care therapy for relapsed and/or refractory MM regardless of relapse timing

Lifestyle and Horizontal Gene Transfer- Mediated Evolution of \u3ci\u3eMucispirillum schaedleri\u3c/i\u3e, a Core Member of the Murine Gut Microbiota

Mucispirillum schaedleri is an abundant inhabitant of the intestinal mucus layer of rodents and other animals and has been suggested to be a pathobiont, a commensal that plays a role in disease. In order to gain insights into its lifestyle, we analyzed the genome and transcriptome of M. schaedleri ASF 457 and performed physiological experiments to test traits predicted by its genome. Although described as a mucus inhabitant, M. schaedleri has limited capacity for degrading host-derived mucosal glycans and other complex polysaccharides. Additionally, M. schaedleri reduces nitrate and expresses systems for scavenging oxygen and reactive oxygen species in vivo, which may account for its localization close to the mucosal tissue and expansion during inflammation. Also of note, M. schaedleri harbors a type VI secretion system and putative effector proteins and can modify gene expression in mucosal tissue, suggesting intimate interactions with its host and a possible role in inflammation. The M. schaedleri genome has been shaped by extensive horizontal gene transfer, primarily from intestinal Epsilon- and Deltaproteobacteria, indicating that horizontal gene transfer has played a key role in defining its niche in the gut ecosystem

Insight into the prebiotic concept: lessons from an exploratory, double blind intervention study with inulin-type fructans in obese women

Objective To highlight the contribution of the gut microbiota to the modulation of host metabolism by dietary inulin-type fructans (ITF prebiotics) in obese women. Methods A double blind, placebo controlled, intervention study was performed with 30 obese women treated with ITF prebiotics (inulin/oligofructose 50/50 mix; n=15) or placebo (maltodextrin; n=15) for 3 months (16 g/day). Blood, faeces and urine sampling, oral glucose tolerance test, homeostasis model assessment and impedancemetry were performed before and after treatment. The gut microbial composition in faeces was analysed by phylogenetic microarray and qPCR analysis of 16S rDNA. Plasma and urine metabolic profiles were analysed by 1H-NMR spectroscopy. Results Treatment with ITF prebiotics, but not the placebo, led to an increase in Bifidobacterium and Faecalibacterium prausnitzii; both bacteria negatively correlated with serum lipopolysaccharide levels. ITF prebiotics also decreased Bacteroides intestinalis, Bacteroides vulgatus and Propionibacterium, an effect associated with a slight decrease in fat mass and with plasma lactate and phosphatidylcholine levels. No clear treatment clustering could be detected for gut microbial analysis or plasma and urine metabolomic profile analyses. However, ITF prebiotics led to subtle changes in the gut microbiota that may importantly impact on several key metabolites implicated in obesity and/or diabetes. Conclusions ITF prebiotics selectively changed the gut microbiota composition in obese women, leading to modest changes in host metabolism, as suggested by the correlation between some bacterial species and metabolic endotoxaemia or metabolomic signatures

Enhanced Functional Recovery in MRL/MpJ Mice after Spinal Cord Dorsal Hemisection

Adult MRL/MpJ mice have been shown to possess unique regeneration capabilities. They are able to heal an ear-punched hole or an injured heart with normal tissue architecture and without scar formation. Here we present functional and histological evidence for enhanced recovery following spinal cord injury (SCI) in MRL/MpJ mice. A control group (C57BL/6 mice) and MRL/MpJ mice underwent a dorsal hemisection at T9 (thoracic vertebra 9). Our data show that MRL/MpJ mice recovered motor function significantly faster and more completely. We observed enhanced regeneration of the corticospinal tract (CST). Furthermore, we observed a reduced astrocytic response and fewer micro-cavities at the injury site, which appear to create a more growth-permissive environment for the injured axons. Our data suggest that the reduced astrocytic response is in part due to a lower lesion-induced increase of cell proliferation post-SCI, and a reduced astrocytic differentiation of the proliferating cells. Interestingly, we also found an increased number of proliferating microglia, which could be involved in the MRL/MpJ spinal cord repair mechanisms. Finally, to evaluate the molecular basis of faster spinal cord repair, we examined the difference in gene expression changes in MRL/MpJ and C57BL/6 mice after SCI. Our microarray data support our histological findings and reveal a transcriptional profile associated with a more efficient spinal cord repair in MRL/MpJ mice