The rockefeller university

Twin CMG complexes are assembled head-to-head around duplex DNA at

The eukaryotic replicative helicase CMG is a closed ring around double-stranded (ds)DNA at origins yet must transition to single-stranded (ss)DNA for helicase action. CMG must also handle repair intermediates, such as reversed forks that lack ssDNA. Here, using correlative single-molecule fluorescence and force microscopy, we show that CMG harbors a ssDNA gate that enables transitions between ss and dsDNA. When coupled to DNA polymerase, CMG remains on ssDNA, but when uncoupled, CMG employs this gate to traverse forked junctions onto dsDNA. Surprisingly, CMG undergoes rapid diffusion on dsDNA and can transition back onto ssDNA to nucleate a functional replisome. The gate-distinct from that between Mcm2/5 used for origin loading-is intrinsic to CMG; however, Mcm10 promotes strand passage by enhancing the affinity of CMG to DNA. This gating process may explain the dsDNA-to-ssDNA transition of CMG at origins and help preserve CMG on dsDNA during fork repair.

Purpose of ReviewIn this review, we summarize the recent literature regarding the incidence and treatment of seizures arising after ischemic and hemorrhagic strokes. Additionally, we identify open questions in guidelines and standard clinical care to aid future studies aiming to improve management of seizures in post-stroke patients.Recent FindingsStudies demonstrate an increasing prevalence of seizures following strokes, probably a consequence of advances in post-stroke management and expanding use of continuous EEG monitoring. Post-stroke seizures are associated with longer hospitalization and increased mortality; therefore, prevention and timely treatment of seizures are important. The standard of care is to treat recurrent seizures with anti-epileptic drugs (AEDs) regardless of the etiology. However, there are no established guidelines currently for prophylactic use of AEDs following a stroke.SummaryThe prevalence of post-stroke seizures is increasing. Further studies are needed to determine the risk factors for recurrent seizures and epilepsy after strokes and optimal treatment strategies.

To define the cell populations that drive joint inflammation in rheumatoid arthritis (RA), we applied single-cell RNA sequencing (scRNA-seq), mass cytometry, bulk RNA sequencing (RNA-seq) and flow cytometry to Tcells, B cells, monocytes, and fibroblasts from 51 samples of synovial tissue from patients with RA or osteoarthritis (OA). Utilizing an integrated strategy based on canonical correlation analysis of 5,265 scRNA-seq profiles, we identified 18 unique cell populations. Combining mass cytometry and transcriptomics revealed cell states expanded in RA synovia: THY1(CD90)(+)HLA-DRA(hi) sublining fibroblasts, IL1B(+) pro-inflammatory monocytes, ITGAX(+)TBX21(+) autoimmune-associated B cells and PDCD1(+) peripheral helper T (T-PH) cells and follicular helper T (T-FH) cells. We defined distinct subsets of CD8(+)Tcells characterized by GZMIK(+), GZMB(+), and GNLY(+) phenotypes. We mapped inflammatory mediators to their source cell populations; for example, we attributed 1L6 expression to THYl(+)HLA-DRA(hi )fibroblasts and IL1B production to pro-inflammatory monocytes. These populations are potentially key mediators of RA pathogenesis.

Ewing sarcoma is characterized by a pathognomonic chromosomal translocation that generates the EWSR1-FLI1 chimeric transcription factor. The transcriptional targets of EWSR1-FLI1 that are essential for tumorigenicity are incompletely defined. Here, we found that EWSR1-FLI1 modulates the expression of cancer/testis (CT) antigen genes, whose expression is biased to the testes but is also activated in cancer. Among these CT antigens, fetal and adult testis expressed 1 (FATE1) is most robustly induced. EWSR1-FLI1 associates with the GGAA repeats in the proximal promoter of FATE1, which exhibits accessible chromatin exclusively in mesenchymal progenitor cells (MPCs) and Ewing sarcoma cells. Expression of EWSR1-FLI1 in non-Ewing sarcoma cells and in MPCs enhances FATE1 mRNA and protein expression. Conversely, depletion of EWSR1-FLI1 in Ewing sarcoma cells leads to a loss of FATE1 expression. Importantly, we found that FATE1 is required for survival and anchorage-independent growth in Ewing sarcoma cells via attenuating the accumulation of BNIP3L, a BH3-only protein that is toxic when stabilized. This action appears to be mediated by the E3 ligase RNF183. We propose that engaging FATE1 function can permit the bypass of cell death mechanisms that would otherwise inhibit tumor progression.

BackgroundBiomedical interventions such as antiretroviral therapy (ART)

Background: Atopic dermatitis (AD) shows differential clinical presentation in older compared with younger patients. Nevertheless, changes in the AD molecular profile with age are unknown. Objective: We sought to characterize age-related changes in the AD profile. Methods: We evaluated age-specific changes in lesional and nonlesional tissues and blood from patients with moderate-to severe AD (n = 246) and age-matched control subjects (n = 71) using immunohistochemistry, quantitative real-time PCR, and Singulex in a cross-sectional study. Patients were analyzed by age group (18-40, 41-60, and >= 61 years). Results: Although disease severity/SCORAD scores were similar across AD age groups (mean, approximately 60 years; P = .873), dendritic cell infiltrates (CD1b(+) and Fc epsilon RI+, P < .05) decreased with age. T(H)2 measures (IL5, IL13, CCL13, CCL18, and CCL26) significantly decreased with age in patients with AD, despite increasing with age in control subjects. Consistent with T(H)2 axis decreases, serum IgE levels and eosinophil counts negatively correlated with age in patients with AD (r = -0.24 and r = -0.23, respectively; P < .05). T(H)22-secreted IL22 expression levels also decreased with age uniquely in patients with AD (P < .05). Expression of T(H)1-related (IFNG, IL12/23p40, STAT1, and CXCL9; P < .05 for CXCL9) and T(H)17-related (IL17A and IL20; P < .05 for IL20) markers increased with age in both patients with AD and control subjects. Expression of terminal differentiation measures significantly increased in older patients with AD (loricrin [LOR] and filaggrin [FLG], P < .05), whereas expression of S100As (S100A8, P < .01) and hyperplasia markers (epidermal thickness, keratin 16, and Ki67; P < .05 for keratin 16) decreased. Serum trends in AD mimicked skin findings, with T(H)2 downregulation (CCL26; r = 0.32, P < .1) and T(H)1 upregulation (IFN-gamma; r = 0.48, P < .01) with age. Conclusion: The adult AD profile varies with age. Although T(H)1/T(H)17 skewing increases in both patients with AD and control subjects, patients with AD show unique decreases in T(H)2/T(H)22 polarization and normalization of epithelial abnormalities. Thus age-specific treatment approaches might be beneficial for AD.

Human whole-genome-sequencing reveals about 4 000 000 genomic variants

Biased ligands preferentially activate certain signaling pathways downstream of their target receptor, leading to differential physiological or behavioral responses downstream. The kappa opioid receptor (KOR) is a drug target for diseases involving mood and reward, such as depression and addiction. Biased KOR ligands offer the potential to overcome negative side effects that have previously hampered the therapeutic development of KOR agonists by preferentially activating certain signaling pathways. Understanding relationships between ligand bias and behavior is difficult, however, because differences in cellular context and bias quantification methods lead to variation between studies. Here, a set of 21 structurally diverse KOR ligands were tested in parallel, to systematically quantify ligand bias at the KOR. Compounds included the endogenous peptide ligand Dynorphin A(1-17), two novel compounds synthesized for our research, and 18 additional compounds of different structural classes, including morphinans and the natural product Salvinorin A. Compounds were tested for their activity in early KOR signaling pathways (G-protein and β-arrestin recruitment) in KOR-expressing U2OS cells, and ligand bias was calculated. A subset of compounds was tested for sedative properties in the rotarod assay in mice. We found that rotarod sedation significantly correlated with β-arrestin signaling in this system, indicating that this in vitro system can be used to accurately describe this in vivo behavior caused by KOR agonists. Additionally, downstream signaling pathways ERK1/2 and mTOR were evaluated, and we determined that signaling via both of these pathways could diverge from KOR-mediated G-protein and arrestin signaling in this system.

Estrogens receptors (ER) are involved in several sociosexual behaviors and fear responses. In particular, the ER alpha is important for sexual behaviors, whereas ER beta modulates anxiolytic responses. Using shRNA directed either against the ER alpha or the ER beta RNAs (or containing luciferase control) encoded within an adeno-associated viral vector, we silenced these receptors in the ventromedial nucleus of the hypothalamus (VMN) and the central amygdala (CeA). We exposed ovariectomized female rats, sequentially treated with estradiol benzoate and progesterone, to five stimuli, previously reported to elicit positive and negative affect. The subjects were housed in groups of 4 females and 3 males in a seminatural environment for several days before hormone treatment. We analyzed the frequency of a large number of behavior patterns. In addition, we performed analyses of co-occurrence in order to detect changes in the structure of behavior after infusion of the vectors. Silencing the ER alpha in the VMN disrupted lordosis and showed some anxiolytic properties in aversive situations, whereas silencing of the ER beta in this structure had no effect. This was also the case after silencing the ER alpha in the CeA. Silencing of the ER beta in this structure increased risk assessment, an expression of anxiety, and increased olfactory exploration of the environment. We hypothesize that the ER beta in the CeA has an important role in the well-established anxiolytic effects of estrogens, and that it may modulate arousal level. Furthermore, it seems that the ER alpha in the VMN is anxiogenic in aversive or threatening situations, in agreement with other studies.