• Fisker Lynn posted an update 14 hours, 33 minutes ago

    Ataxin-1 (ATXN1) is a ubiquitous polyglutamine protein expressed primarily in the nucleus where it binds chromatin and functions as a transcriptional repressor. Mutant forms of ataxin-1 containing expanded glutamine stretches cause the movement disorder spinocerebellar ataxia type 1 (SCA1) through a toxic gain-of-function mechanism in the cerebellum. Conversely, ATXN1 loss-of-function is implicated in cancer development and Alzheimer’s disease (AD) pathogenesis. this website ATXN1 was recently nominated as a susceptibility locus for multiple sclerosis (MS). Here, we show that Atxn1-null mice develop a more severe experimental autoimmune encephalomyelitis (EAE) course compared to wildtype mice. The aggravated phenotype is mediated by increased T helper type 1 (Th1) cell polarization, which in turn results from the dysregulation of B cell activity. Ataxin-1 ablation in B cells leads to aberrant expression of key costimulatory molecules involved in proinflammatory T cell differentiation, including cluster of differentiation (CD)44 and CD80. In addition, comprehensive phosphoflow cytometry and transcriptional profiling link the exaggerated proliferation of ataxin-1 deficient B cells to the activation of extracellular signal-regulated kinase (ERK) and signal transducer and activator of transcription (STAT) pathways. Lastly, selective deletion of the physiological binding partner capicua (CIC) demonstrates the importance of ATXN1 native interactions for correct B cell functioning. Altogether, we report a immunomodulatory role for ataxin-1 and provide a functional description of the ATXN1 locus genetic association with MS risk.Intracellular pathogens are responsible for an enormous amount of worldwide morbidity and mortality, and each has evolved specialized strategies to establish and maintain their replicative niche. Listeria monocytogenes is a facultative intracellular pathogen that secretes a pore-forming cytolysin called listeriolysin O (LLO), which disrupts the phagosomal membrane and, thereby, allows the bacteria access to their replicative niche in the cytosol. Nonsynonymous and synonymous mutations in a PEST-like domain near the LLO N terminus cause enhanced LLO translation during intracellular growth, leading to host cell death and loss of virulence. Here, we explore the mechanism of translational control and show that there is extensive codon restriction within the PEST-encoding region of the LLO messenger RNA (mRNA) (hly). This region has considerable complementarity with the 5′ UTR and is predicted to form an extensive secondary structure that overlaps the ribosome binding site. Analysis of both 5′ UTR and synonymous mutations in the PEST-like domain that are predicted to disrupt the secondary structure resulted in up to a 10,000-fold drop in virulence during mouse infection, while compensatory double mutants restored virulence to WT levels. We showed by dynamic protein radiolabeling that LLO synthesis was growth phase-dependent. These data provide a mechanism to explain how the bacteria regulate translation of LLO to promote translation during starvation in a phagosome while repressing it during growth in the cytosol. These studies also provide a molecular explanation for codon bias at the 5′ end of this essential determinant of pathogenesis.Alkanes and [B12X12]2- (X = Cl, Br) are both stable compounds which are difficult to functionalize. Here we demonstrate the formation of a boron-carbon bond between these substances in a two-step process. Fragmentation of [B12X12]2- in the gas phase generates highly reactive [B12X11]- ions which spontaneously react with alkanes. The reaction mechanism was investigated using tandem mass spectrometry and gas-phase vibrational spectroscopy combined with electronic structure calculations. [B12X11]- reacts by an electrophilic substitution of a proton in an alkane resulting in a B-C bond formation. The product is a dianionic [B12X11CnH2n+1]2- species, to which H+ is electrostatically bound. High-flux ion soft landing was performed to codeposit [B12X11]- and complex organic molecules (phthalates) in thin layers on surfaces. Molecular structure analysis of the product films revealed that C-H functionalization by [B12X11]- occurred in the presence of other more reactive functional groups. This observation demonstrates the utility of highly reactive fragment ions for selective bond formation processes and may pave the way for the use of gas-phase ion chemistry for the generation of complex molecular structures in the condensed phase.

    Patients with inflammatory rheumatic diseases (IRD) infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be at risk to develop a severe course of COVID-19. The influence of immunomodulating drugs on the course of COVID-19 is unknown. To gather knowledge about SARS-CoV-2 infections in patients with IRD, we established a registry shortly after the beginning of the pandemic in Germany.

    Using an online questionnaire (www.COVID19-rheuma.de), a nationwide database was launched on 30 March 2020, with appropriate ethical and data protection approval to collect data of patients with IRD infected with SARS-CoV-2. In this registry, key clinical and epidemiological parameters-for example, diagnosis of IRD, antirheumatic therapies, comorbidities and course of the infection-are documented.

    Until 25 April 2020, data from 104 patients with IRD infected with SARS-CoV-2 were reported (40 males; 63 females; 1 diverse). Most of them (45%) were diagnosed with rheumatoid arthritis, 59% had one or mogain a better understanding of the course of SARS-CoV2-infection in patients with IRD, with a distinct focus on their immunomodulatory therapies. This knowledge is valuable for timely information of physicians and patients with IRD, and shall also serve for the development of guidance for the management of patients with IRD during this pandemic.

    To test the hypothesis that end-stage renal disease (ESRD) risk exposure during young adulthood is related to worse cognitive performance in midlife.

    We included 2,604 participants from the population-based Coronary Artery Risk Development in Young Adults (CARDIA) Study (mean age 35 years, 54% women, 45% Black). Estimated glomerular filtration rate and albumin-to-creatinine ratio were measured every 5 years at year (Y) 10 through Y30. At each visit, moderate/high risk of ESRD according to the Kidney Disease Improving Global Outcomes guidelines (estimated glomerular filtration rate <60 mL/min/1.73 m

    or albumin-to-creatinine ratio >30 mg/g) was defined, totaled over examinations, and categorized into 0 episodes, 1 episode, and >1 episodes of ESRD risk. At Y30, participants underwent global and multidomain cognitive assessment. We used analysis of covariance to assess the association of ESRD risk categories with cognitive function, controlling for cardiovascular risk factors.

    Over the course of 20 years, 427 participants (16% of the study population) had ≥1 episodes of ESRD risk exposure.