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Werren, J. H.

Publications and source records attributed to Werren, J. H..

7 recordsLinked to original sources

Evolutionary Inference Predicts Novel ACE2 Protein Interactions Relevant to COVID-19 Pathologies

Angiotensin-converting enzyme 2 (ACE2) is the cell receptor that the coronavirus SARS-CoV-2 binds to and uses to enter and infect human cells. COVID-19, the pandemic disease caused by the coronavirus, involves diverse pathologies beyond those of a respiratory disease, including micro-thrombosis (micro-clotting), cytokine storms, and inflammatory responses affecting many organ systems. Longer-term chronic illness can persist for many months, often well after the pathogen is no longer detected. A better understanding of the proteins that ACE2 interacts with can reveal information relevant to these disease manifestations and possible avenues for treatment. We have undertaken an approach to predict candidate ACE2 interacting proteins which uses evolutionary inference to identify a set of mammalian proteins that "coevolve" with ACE2. The approach, called evolutionary rate correlation (ERC), detects proteins that show highly correlated evolutionary rates during mammalian evolution. Such proteins are candidates for biological interactions with the ACE2 receptor. The approach has uncovered a number of key ACE2 protein interactions of potential relevance to COVID-19 pathologies. Some proteins have previously been reported to be associated with severe COVID-19, but are not currently known to interact directly with ACE2, while additional predicted novel ACE2 interactors are of potential relevance to the disease. Using reciprocal rankings of protein ERCs, we have identified strongly interconnected ACE2 associated protein networks relevant to COVID-19 pathologies. ACE2 has clear connections to coagulation pathway proteins, such as Coagulation Factor V and fibrinogen components FGG, FGB, and FGA, the latter possibly mediated through ACE2 connections to Clusterin (which clears misfolded extracellular proteins) and GPR141 (whose functions are relatively unknown). ACE2 also connects to proteins involved in cytokine signaling and immune response (e.g. IFNAR2, XCR1, and TLR8), and to Androgen Receptor (AR). The ERC prescreening approach has also elucidated possible functions for previously uncharacterized proteins and possible new functions for well-characterized ones. Suggestions are made for the validation of ERC predicted ACE2 protein interactions. We propose that ACE2 has novel protein interactions that are disrupted during SARS-CoV-2 infection, contributing to the spectrum of COVID-19 pathologies.

bioinformatics↗

Genetic, morphometric, and molecular analyses of interspecies differences in head shape and hybrid developmental defects in the wasp genus Nasonia

Males in the parasitoid wasp genus Nasonia (N. vitripennis, N. giraulti, N. longicornis) have distinct, species specific, head shapes. Fertile hybrids among the species are readily produced in the lab allowing genetic analysis of the evolved differences. In addition, the obligate haploidy of males makes these wasps a uniquely powerful model for analyzing the role of complex gene interactions in development and evolution. Previous analyses have shown that complex gene interactions underpin different aspects of the shape differences, and developmental incompatibilities that are specific to the head in F2 haploid hybrid males are also governed by networks of gene interaction. Here we use the genetic tools available in Nasonia to extend our understanding of the gene interactions that affect development and morphogenesis in male heads. Using artificial diploid male hybrids, we show that alleles affecting head shape are codominant, leading to uniform, averaged hybrid F1 diploid male heads, while the alleles mediating developmental defects are recessive, and are not visible in the diploid hybrids. We also determine that divergence in time, rather than in morphological disparity is the primary driver of hybrid developmental defects. In addition, we show that doublesex is necessary for the male head shape differences, but is not the only important factor. Finally we demonstrate that we can dissect complex interspecies gene interaction networks using introgression in this system. These advances represent significant progress in the complex web of gene interactions that govern morphological development, and chart the connections between genomic and phenotypic variation.

evolutionary biology↗

Functional genomics of the stable fly, Stomoxys calcitrans, reveals mechanisms underlying reproduction, host interactions, and novel targets for pest control

BackgroundThe stable fly, Stomoxys calcitrans, is a major blood-feeding pest of livestock that has near worldwide distribution, causing an annual cost of over $2 billion for control and product loss in the United States alone. Control of these flies has been limited to increased sanitary management practices and insecticide application for suppressing larval stages. Few genetic and molecular resources are available to help in developing novel methods for controlling stable flies.\n\nResultsThis study examines stable fly biology by utilizing a combination of high-quality genome sequencing, microbiome analyses, and RNA-seq analyses targeting multiple developmental stages and tissues. In conjunction, manual curation of over 1600 genes was used to examine gene content related to stable fly reproduction, interactions with their host, host-microbe dynamics, and putative routes for control. Most notable was establishment of reproduction-associated genes and identification of expanded vision, chemosensation, immune repertoire, and metabolic detoxification pathway gene families.\n\nConclusionsThe combined sequencing, assembly, and curation of the male stable fly genome followed by RNA-seq and downstream analyses provide insights necessary to understand the biology of this important pest. These resources and knowledge will provide the groundwork for expanding the tools available to control stable fly infestations. The close relationship of Stomoxys to other blood-feeding (Glossina) and non-blood-feeding flies (medflies, Drosophila, house flies) will allow for understanding the evolution of blood feeding among Cyclorrhapha flies.

genomics↗

Sex biased expression and co-expression networks in development, using the hymenopteran Nasonia vitripennis

Sexual dimorphism requires gene expression regulation in developing organisms. Differential expression, alternative splicing and transcript-transcript interactions all contribute to developmental differences between the sexes. However, few studies have described how these processes change across developmental stages, or how they interact to form co-expression networks. We compare the dynamics of all three regulatory processes in the sexual development of the model parasitoid wasp Nasonia vitripennis, a system that permits genome wide analysis of sex bias from early embryos to adults. We find relatively little sex-bias in embryos and larvae at the whole-gene level, but several sub-networks show sex-biased transcript-transcript interactions in early developmental stages. These provide new candidates for hymenopteran sex determination, including histone modification genes. In contrast, sex-bias in pupae and adults is driven by whole-gene differential expression. We observe sex-biased splicing consistently across development, but mostly in genes that are already biased at the whole-gene level. Finally, we discover that sex-biased networks are enriched by genes specific to the Nasonia clade, and that those genes possess the topological properties of key regulators. These findings suggest that regulators in sex-biased networks evolve more rapidly than regulators of other developmental networks.

evolutionary biology↗

Mitochondrial DNA and their nuclear copies in parasitic wasp Pteromalus puparum: A comparative analysis in Chalcidoidea

Chalcidoidea (chalcidoid wasps) are an abundant and megadiverse insect group with both ecological and economical importance. Here we report a complete mitochondrial genome in Chalcidoidea from Pteromalus puparum (Pteromalidae). Eight tandem repeats followed by 6 reversed repeats were detected in its 3,308 bp control region. This long and complex control region may explain failures of amplifying and sequencing of complete mitochondrial genomes in some chalcidoids. In addition to 37 typical mitochondrial genes, an extra identical isoleucine tRNA (trnI) was detected. We speculate this recent mitochondrial gene duplication indicates that gene arrangements in chalcidoids are ongoing. A comparison among available chalcidoid mitochondrial genomes, reveals rapid gene order rearrangements overall, and high substitution rate in P. puparum. In addition, we identified 24 nuclear sequences of mitochondrial origin (NUMTs) in P. puparum, summing up to 9,989 bp, with 3,617 bp of these NUMTs originating from mitochondrial coding regions. NUMTs abundance in P. puparum is only one-twelfth of that in its relative, Nasonia vitripennis. Based on phylogenetic analysis, we provide evidence that a faster nuclear degradation rate contributes to the reduced NUMT numbers in P. puparum. Overall, our study shows unusually high rates of mitochondrial evolution and considerable variation in NUMT accumulation in Chalcidoidea.

genomics↗

Parasitoid wasp venom elevates sorbitol and alters expression of metabolic genes in human kidney cells

Venom from the parasitoid wasp Nasonia vitripennis dramatically elevates sorbitol levels in its natural fly hosts. In humans, sorbitol elevation is associated with complications of diabetes. Here we demonstrate that venom also induces this disease-relevant phenotype in human cells, and investigate possible pathways involved. Key findings are that (a) low doses of Nasonia venom elevate sorbitol levels in human renal mesangial cells (HRMCs) without changing glucose or fructose levels; (b) venom is a much more potent inducer of sorbitol elevation than glucose; (c) low venom doses significantly alter expression of genes involved in sterol and alcohol metabolism, transcriptional regulation, and chemical/stimulus response; (d) although venom treatment does not alter expression of the key sorbitol pathway gene aldose reductase (AR); (e) venom elevates expression of a related gene implicated in diabetes complications (AKR1C3) as well as the fructose metabolic gene (GFPT2). Although elevated sorbitol is accepted as a major contributor to secondary complications of diabetes, the molecular mechanism of sorbitol regulation and its contribution to diabetes complications are not fully understood. Our findings suggest that genes other than AR could contribute to sorbitol regulation, and more broadly illustrate the potential of parasitoid venoms for medical application.

pharmacology and toxicology↗

Molecular evolutionary trends and feeding ecology diversification in the Hemiptera, anchored by the milkweed bug genome

BackgroundThe Hemiptera (aphids, cicadas, and true bugs) are a key insect order, with high diversity for feeding ecology and excellent experimental tractability for molecular genetics. Building upon recent sequencing of hemipteran pests such as phloem-feeding aphids and blood-feeding bed bugs, we present the genome sequence and comparative analyses centered on the milkweed bug Oncopeltus fasciatus, a seed feeder of the family Lygaeidae.\n\nResultsThe 926-Mb Oncopeltus genome is well represented by the current assembly and official gene set. We use our genomic and RNA-seq data not only to characterize the protein-coding gene repertoire and perform isoform-specific RNAi, but also to elucidate patterns of molecular evolution and physiology. We find ongoing, lineage-specific expansion and diversification of repressive C2H2 zinc finger proteins. The discovery of intron gain and turnover specific to the Hemiptera also prompted evaluation of lineage and genome size as predictors of gene structure evolution. Furthermore, we identify enzymatic gains and losses that correlate with feeding biology, particularly for reductions associated with derived, fluid-nutrition feeding.\n\nConclusionsWith the milkweed bug, we now have a critical mass of sequenced species for a hemimetabolous insect order and close outgroup to the Holometabola, substantially improving the diversity of insect genomics. We thereby define commonalities among the Hemiptera and delve into how hemipteran genomes reflect distinct feeding ecologies. Given Oncopeltus's strength as an experimental model, these new sequence resources bolster the foundation for molecular research and highlight technical considerations for the analysis of medium-sized invertebrate genomes.

genomics↗