28 research outputs found
Polydnavirus genomes reflect their dual roles as mutualists and pathogens
AbstractSymbionts often exhibit significant reductions in genome complexity while pathogens often exhibit increased complexity through acquisition and diversification of virulence determinants. A few organisms have evolved complex life cycles in which they interact as symbionts with one host and pathogens with another. How the predicted and opposing influences of symbiosis and pathogenesis affect genome evolution in such instances, however, is unclear. The Polydnaviridae is a family of double-stranded (ds) DNA viruses associated with parasitoid wasps that parasitize other insects. Polydnaviruses (PDVs) only replicate in wasps but infect and cause severe disease in parasitized hosts. This disease is essential for survival of the parasitoid's offspring. Thus, a true mutualism exists between PDVs and wasps as viral transmission depends on parasitoid survival and parasitoid survival depends on viral infection of the wasp's host. To investigate how life cycle and ancestry affect PDVs, we compared the genomes of Campoletis sonorensis ichnovirus (CsIV) and Microplitis demolitor bracovirus (MdBV). CsIV and MdBV have no direct common ancestor, yet their encapsidated genomes share several features including segmentation, diversification of virulence genes into families, and the absence of genes required for replication. In contrast, CsIV and MdBV share few genes expressed in parasitized hosts. We conclude that the similar organizational features of PDV genomes reflect their shared life cycle but that PDVs associated with ichneumonid and braconid wasps have likely evolved different strategies to cause disease in the wasp's host and promote parasitoid survival
In Vitro and In Silico Analyses of the Inhibition of Human Aldehyde Oxidase by Bazedoxifene, Lasofoxifene, and Structural Analogues
Aldehyde oxidase (AOX1) is a molybdo-flavoprotein and has emerged as a drug-metabolizing enzyme of potential therapeutic importance because drugs have been identified as AOX1 substrates. Selective oestrogen receptor modulators (SERM), which are drugs used to treat and prevent various conditions, differentially inhibit AOX1 catalytic activity. Tamoxifen, raloxifene, and nafoxidine are selective oestrogen receptor modulators (SERMs) reported to inhibit the catalytic activity of human aldehyde oxidase 1 (AOX1). How these drugs interact with AOX1 and whether other SERMs inhibit this drug-metabolizing enzyme are not known. Therefore, a detailed in vitro and in silico study involving parent drugs and their analogues was conducted to investigate the effect of specific SERMs, particularly acolbifene, bazedoxifene, and lasofoxifene on AOX1 catalytic activity, as assessed by carbazeran 4-oxidation, an AOX1-selective catalytic marker. The rank-order in the potency (based on IC50 values) of AOX1 inhibition by SERMs was raloxifene > bazedoxifene ~ lasofoxifene > tamoxifen > acolbifene. Inhibition of liver cytosolic AOX1 by bazedoxifene, lasofoxifene, and tamoxifen was competitive, whereas that by raloxifene was noncompetitive. Loss of 1-azepanylethyl group increased the inhibitory potency of bazedoxifene, whereas the N-oxide group decreased it. The 7-hydroxy group and the substituted pyrrolidine ring attached to the tetrahydronaphthalene structure contributed to AOX1 inhibition by lasofoxifene. These results are supported by molecular docking simulations in terms of predicted binding modes, encompassing binding orientation and efficiency, and analysis of key interactions, particularly hydrogen bonds. The extent of AOX1 inhibition by bazedoxifene was increased by estrone sulfate and estrone. In summary, SERMs differentially inhibited human AOX1 catalytic activity. Structural features of bazedoxifene and lasofoxifene contributed to AOX1 inhibition, whereas those of acolbifene rendered it considerably less susceptible to AOX1 inhibition. Overall, our novel biochemical findings and molecular docking analyses provide new insights into the interaction between SERMs and AOX1. Structural features of bazedoxifene and lasofoxifene contribute to AOX1 inhibition, whereas those of acolbifene render it considerably less susceptible to AOX1 inhibition. Our novel biochemical findings, together with molecular docking analyses, provide new insights into the differential inhibitory effect of SERMs on the catalytic activity of human AOX1, how SERMs bind to AOX1, and increase our understanding of the AOX1 pharmacophore in the inhibition of AOX1 by drugs and other chemicals
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Stroke genetics informs drug discovery and risk prediction across ancestries
Previous genome-wide association studies (GWASs) of stroke - the second leading cause of death worldwide - were conducted predominantly in populations of European ancestry(1,2). Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis(3), and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach(4), we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry(5). Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries.</p
Stroke genetics informs drug discovery and risk prediction across ancestries
Previous genome-wide association studies (GWASs) of stroke — the second leading cause of death worldwide — were conducted predominantly in populations of European ancestry1,2. Here, in cross-ancestry GWAS meta-analyses of 110,182 patients who have had a stroke (five ancestries, 33% non-European) and 1,503,898 control individuals, we identify association signals for stroke and its subtypes at 89 (61 new) independent loci: 60 in primary inverse-variance-weighted analyses and 29 in secondary meta-regression and multitrait analyses. On the basis of internal cross-ancestry validation and an independent follow-up in 89,084 additional cases of stroke (30% non-European) and 1,013,843 control individuals, 87% of the primary stroke risk loci and 60% of the secondary stroke risk loci were replicated (P < 0.05). Effect sizes were highly correlated across ancestries. Cross-ancestry fine-mapping, in silico mutagenesis analysis3, and transcriptome-wide and proteome-wide association analyses revealed putative causal genes (such as SH3PXD2A and FURIN) and variants (such as at GRK5 and NOS3). Using a three-pronged approach4, we provide genetic evidence for putative drug effects, highlighting F11, KLKB1, PROC, GP1BA, LAMC2 and VCAM1 as possible targets, with drugs already under investigation for stroke for F11 and PROC. A polygenic score integrating cross-ancestry and ancestry-specific stroke GWASs with vascular-risk factor GWASs (integrative polygenic scores) strongly predicted ischaemic stroke in populations of European, East Asian and African ancestry5. Stroke genetic risk scores were predictive of ischaemic stroke independent of clinical risk factors in 52,600 clinical-trial participants with cardiometabolic disease. Our results provide insights to inform biology, reveal potential drug targets and derive genetic risk prediction tools across ancestries