Current eukaryotic replication models postulate that leading and lagging DNA strands are replicated predominantly by dedicated DNA polymerases. The catalytic subunit of the leading strand DNA polymerase ε, Pol2, consists of two halves made of two different ancestral B-family DNA polymerases. Counterintuitively, the catalytically active N-terminal half is dispensable, while the inactive C-terminal part is required for viability. Despite extensive studies of yeast Saccharomyces cerevisiae strains lacking the active N-terminal half, it is still unclear how these strains survive and recover. We designed a robust method for constructing mutants with only the C-terminal part of Pol2. Strains without the active polymerase part show severe growth defects, sensitivity to replication inhibitors, chromosomal instability, and elevated spontaneous mutagenesis. Intriguingly, the slow-growing mutant strains rapidly accumulate fast-growing clones. Analysis of genomic DNA sequences of these clones revealed that the adaptation to the loss of the catalytic N-terminal part of Pol2 occurs by a positive selection of mutants with improved growth. Elevated mutation rates help generate sufficient numbers of these variants.  https://www.selleckchem.com/products/bos172722.html  Single nucleotide changes in the cell cycle-dependent kinase gene, CDC28, improve the growth of strains lacking the N-terminal part of Pol2, and rescue their sensitivity to replication inhibitors and, in parallel, lower mutation rates. Our study predicts that changes in mammalian homologs of cyclin-dependent kinases may contribute to cellular responses to the leading strand polymerase defects.Species tree estimation from multi-locus datasets is extremely challenging, especially in the presence of gene tree heterogeneity across the genome due to incomplete lineage sorting (ILS). Summary methods have been developed which estimate gene trees and then combine the gene trees to estimate a species tree by optimizing various optimization scores. In this study, we have extended and adapted the concept of phylogenetic terraces to species tree estimation by "summarizing" a set of gene trees, where multiple species trees with distinct topologies may have exactly the same optimality score (i.e., quartet score, extra lineage score, etc.). We particularly investigated the presence and impacts of equally optimal trees in species tree estimation from multi-locus data using summary methods by taking ILS into account. We analyzed two of the most popular ILS-aware optimization criteria maximize quartet consistency (MQC) and minimize deep coalescence (MDC). Methods based on MQC are provably statistically consistent, whereas MDC is not a consistent criterion for species tree estimation. We present a comprehensive comparative study of these two optimality criteria. Our experiments, on a collection of datasets simulated under ILS, indicate that MDC may result in competitive or identical quartet consistency score as MQC, but could be significantly worse than MQC in terms of tree accuracy - demonstrating the presence and impacts of equally optimal species trees. This is the first known study that provides the conditions for the datasets to have equally optimal trees in the context of phylogenomic inference using summary methods.
  The efficacy of the novel interleukin (IL)-23p19 inhibitor guselkumab for psoriatic arthritis (PsA) has recently been demonstrated in two phase 3 trials (DISCOVER-1 & -2) but has not been evaluated vs other targeted therapies for PsA. The objective was to compare guselkumab to targeted therapies for PsA for safety and joint and skin efficacy through network meta-analysis (NMA).
 
  A systematic literature review was conducted in January 2020 to identify randomized controlled trials. Bayesian NMAs were performed to compare treatments on American College of Rheumatology (ACR) 20/50/70 response, mean change from baseline in van der Heijde-Sharp (vdH-S) score, Psoriasis Area Severity Index (PASI) 75/90/100 response, adverse events (AEs) and serious adverse events (SAEs).
 
  Twenty-six phase 3 studies evaluating 13 targeted therapies for PsA were included. For ACR 20 response, guselkumab 100 mg every 8 weeks (Q8W) was comparable to IL-17A inhibitors and subcutaneous tumor necrosis factor (TNF) inhibitors. Similar findings were observed for ACR 50 and 70. For vdH-S score, guselkumab Q8W was comparable to other agents except intravenous TNF therapies. Results for PASI 75 and PASI 90 response suggested guselkumab Q8W was better than most other agents. For PASI 100, guselkumab Q8W was comparable to other active agents. For AEs and SAEs, guselkumab Q8W ranked highly but comparative conclusions were uncertain. Similar results were observed for all outcomes for guselkumab 100 mg every four weeks.
 
  In this NMA, guselkumab demonstrated favorable arthritis efficacy comparable to IL-17A and subcutaneous TNF inhibitors while offering better PASI response relative to many other treatments.
 In this NMA, guselkumab demonstrated favorable arthritis efficacy comparable to IL-17A and subcutaneous TNF inhibitors while offering better PASI response relative to many other treatments.
  Coinfection with HIV-1 and HTLV-1 diminishes the value of the CD4 + T-cell count in diagnosing AIDS, and increases the rate of HTLV-1-associated myelopathy. It remains elusive how HIV-1/HTLV-1 coinfection is related to such clinical characteristics. Here, we investigated the mutual effect of HIV-1/HTLV-1 coinfection on their integration sites (ISs) and the clonal expansion.
 
  We extracted DNA from longitudinal peripheral blood samples from 7 HIV-1/HTLV-1 coinfected individuals, and from 12 HIV-1 and 13 HTLV-1 mono-infected individuals. The proviral loads (PVL) were quantified using real-time PCR. Viral ISs and clonality were quantified by ligation-mediated PCR followed by high-throughput sequencing.
 
  The PVL of both HIV-1 and HTLV-1 in coinfected individuals was significantly higher than that of the respective virus in mono-infected individuals. The degree of oligoclonality of both HIV-1- and HTLV-1-infected cells in co-infected individuals was also greater than that in mono-infected subjects. The ISs of HIV-1 in cases of coinfection were more frequently located in intergenic regions and transcriptionally silent regions, compared with HIV-1 mono-infected individuals.