The evolutionary dynamics of venom toxins made by insects and other animals

2020 ◽  
Vol 48 (4) ◽  
pp. 1353-1365
Author(s):  
Andrew A. Walker
Keyword(s):  
Evolutionary Dynamics ◽  
Host Responses ◽  
Selection Pressures ◽  
Insect Venom ◽  
Venom Toxins ◽  
Venomous Animals ◽  
Genetic Mechanisms ◽  
Encoding Genes ◽  
Animal Venoms ◽  
Toxin Evolution

Animal venoms are recognised as unique biological systems in which to study molecular evolution. Venom use has evolved numerous times among the insects, and insects today use venom to capture prey, defend themselves from predators, or to subdue and modulate host responses during parasitism. However, little is known about most insect venom toxins or the mode and tempo by which they evolve. Here, I review the evolutionary dynamics of insect venom toxins, and argue that insects offer many opportunities to examine novel aspects of toxin evolution. The key questions addressed are: How do venomous animals evolve from non-venomous animals, and how does this path effect the composition and pharmacology of the venom? What genetic processes (gene duplication, co-option, neofunctionalisation) are most important in toxin evolution? What kinds of selection pressures are acting on toxin-encoding genes and their cognate targets in envenomated animals? The emerging evidence highlights that venom composition and pharmacology adapts quickly in response to changing selection pressures resulting from new ecological interactions, and that such evolution occurs through a stunning variety of genetic mechanisms. Insects offer many opportunities to investigate the evolutionary dynamics of venom toxins due to their evolutionary history rich in venom-related adaptations, and their quick generation time and suitability for culture in the laboratory.

scholarly journals Evolutionary Ecology of Fish Venom: Adaptations and Consequences of Evolving a Venom System

Toxins ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 60 ◽  
Author(s):  
Richard J. Harris ◽  
Ronald A. Jenner
Keyword(s):  
Natural Enemy ◽  
Evolutionary Ecology ◽  
The Other ◽  
Ecological Consequences ◽  
Biological Relevance ◽  
Venom Toxins ◽  
Venomous Animals ◽  
Animal Venoms

Research on venomous animals has mainly focused on the molecular, biochemical, and pharmacological aspects of venom toxins. However, it is the relatively neglected broader study of evolutionary ecology that is crucial for understanding the biological relevance of venom systems. As fish have convergently evolved venom systems multiple times, it makes them ideal organisms to investigate the evolutionary ecology of venom on a broader scale. This review outlines what is known about how fish venom systems evolved as a result of natural enemy interactions and about the ecological consequences of evolving a venom system. This review will show how research on the evolutionary ecology of venom in fish can aid in understanding the evolutionary ecology of animal venoms more generally. Further, understanding these broad ecological questions can shed more light on the other areas of toxinology, with applications across multiple disciplinary fields.

Animal Venoms have Potential to Treat Cancer

2019 ◽  
Vol 18 (30) ◽  
pp. 2555-2566 ◽  
Author(s):  
Bhaswati Chatterjee
Keyword(s):  
Cancer Therapeutics ◽  
Sea Anemones ◽  
Anticancer Activities ◽  
Inhibition Of Proliferation ◽  
Cycle Arrest ◽  
Venomous Animals ◽  
Anti Cancer ◽  
Cancerous Cells ◽  
Animal Venoms ◽  
Proteins And Peptides

The resistance to chemotherapeutics by the cancerous cells has made its treatment more complicated. Animal venoms have emerged as an alternative strategy for anti-cancer therapeutics. Animal venoms are cocktails of complex bioactive chemicals mainly disulfide-rich proteins and peptides with diverse pharmacological actions. The components of venoms are specific, stable, and potent and have the ability to modify their molecular targets thus making them good therapeutics candidates. The isolation of cancer-specific components from animal venoms is one of the exciting strategies in anti-cancer research. This review highlights the identified venom peptides and proteins from different venomous animals like snakes, scorpions, spiders, bees, wasps, snails, toads, frogs and sea anemones and their anticancer activities including inhibition of proliferation of cancer cells, their invasion, cell cycle arrest, induction of apoptosis and the identification of involved signaling pathways.

scholarly journals Machine learning can differentiate venom toxins from other proteins having non-toxic physiological functions

2016 ◽  
Vol 2 ◽  
pp. e90 ◽  
Author(s):  
Ranko Gacesa ◽  
David J. Barlow ◽  
Paul F. Long
Keyword(s):  
Machine Learning ◽  
Sequence Data ◽  
Biological Data ◽  
Biological Databases ◽  
Web Based ◽  
Physiological Functions ◽  
Link Type ◽  
Venom Toxins ◽  
Venomous Animals ◽  
Toxin Protein

Ascribing function to sequence in the absence of biological data is an ongoing challenge in bioinformatics. Differentiating the toxins of venomous animals from homologues having other physiological functions is particularly problematic as there are no universally accepted methods by which to attribute toxin function using sequence data alone. Bioinformatics tools that do exist are difficult to implement for researchers with little bioinformatics training. Here we announce a machine learning tool called ‘ToxClassifier’ that enables simple and consistent discrimination of toxins from non-toxin sequences with >99% accuracy and compare it to commonly used toxin annotation methods. ‘ToxClassifer’ also reports the best-hit annotation allowing placement of a toxin into the most appropriate toxin protein family, or relates it to a non-toxic protein having the closest homology, giving enhanced curation of existing biological databases and new venomics projects. ‘ToxClassifier’ is available for free, either to download (https://github.com/rgacesa/ToxClassifier) or to use on a web-based server (http://bioserv7.bioinfo.pbf.hr/ToxClassifier/).

scholarly journals Genomics of Avian Viral Infections

Genes ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 814 ◽  
Author(s):  
Smith
Keyword(s):  
Viral Infections ◽  
Current Knowledge ◽  
Host Susceptibility ◽  
Host Responses ◽  
Economic Losses ◽  
Poultry Industry ◽  
Special Issue ◽  
Viral Pathogens ◽  
Genetic Mechanisms ◽  
Global Population

The poultry industry currently accounts for the production of around 118 million metric tons of meat and around 74 million metric tons of eggs annually. As the global population continues to increase, so does our reliance on poultry as a food source. It is therefore of vital importance that we safeguard this valuable resource and make the industry as economically competitive as possible. Avian viral infections, however, continue to cost the poultry industry billions of dollars annually. This can be in terms of vaccination costs, loss of birds and decreased production. With a view to improving the health and welfare of commercial birds and to minimizing associated economic losses, it is therefore of great importance that we try to understand the genetic mechanisms underlying host susceptibility and resilience to some of the major viral pathogens that threaten the poultry species. Some avian viruses, through their zoonotic potential, also pose a risk to human health. This Special Issue will present papers that describe our current knowledge on host responses to various viral pathogens, the genetics underlying those responses and how genomics can begin to provide a solution for resolving the threat posed by these infections.

scholarly journals Positive selection of ORF3a and ORF8 genes drives the evolution of SARS-CoV-2 during the 2020 COVID-19 pandemic

2020 ◽  
Author(s):  
Lauro Velazquez-Salinas ◽  
Selene Zarate ◽  
Samantha Eberl ◽  
Douglas P. Gladue ◽  
Isabel Novella ◽  
...  
Keyword(s):  
Public Health ◽  
Positive Selection ◽  
Evolutionary Dynamics ◽  
Full Length ◽  
Accessory Proteins ◽  
The Novel ◽  
Phylogenetic Groups ◽  
Epistatic Interactions ◽  
Genetic Mechanisms ◽  
Selection Of

AbstractIn this study, we analyzed full-length SARS-CoV-2 genomes from multiple countries to determine early trends in the evolutionary dynamics of the novel COVID-19 pandemic. Results indicated SARS-CoV-2 evolved early into at least three phylogenetic groups, characterized by positive selection at specific residues of the accessory proteins OFR3a and ORF8a. We also report evidence of epistatic interactions among sites in the genome that may be important in the generation of variants adapted to humans. These observations might impact not only public health, but also suggest more studies are needed to understand the genetic mechanisms that may affect the development of therapeutic and preventive tools, like antivirals and vaccines.

scholarly journals Molecular Characterization of UpaB and UpaC, Two New Autotransporter Proteins of Uropathogenic Escherichia coli CFT073

2011 ◽  
Vol 80 (1) ◽  
pp. 321-332 ◽  
Author(s):  
Luke P. Allsopp ◽  
Christophe Beloin ◽  
Glen C. Ulett ◽  
Jaione Valle ◽  
Makrina Totsika ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Molecular Characterization ◽  
Host Responses ◽  
Upec Strain ◽  
Content Type ◽  
Pcr Screening ◽  
E Coli ◽  
K 12 ◽  
Encoding Genes

ABSTRACTUropathogenicEscherichia coli(UPEC) is the primary cause of urinary tract infection (UTI) in the developed world. The major factors associated with virulence of UPEC are fimbrial adhesins, which mediate specific attachment to host receptors and trigger innate host responses. Another group of adhesins is represented by the autotransporter (AT) subgroup of proteins. The genome-sequenced prototype UPEC strain CFT073 contains 11 putative AT-encoding genes. In this study, we have performed a detailed molecular characterization of two closely related AT adhesins from CFT073: UpaB (c0426) and UpaC (c0478). PCR screening revealed that theupaBandupaCAT-encoding genes are common inE. coli. TheupaBandupaCgenes were cloned and characterized in a recombinantE. coliK-12 strain background. This revealed that they encode proteins located at the cell surface but possess different functional properties: UpaB mediates adherence to several ECM proteins, while UpaC expression is associated with increased biofilm formation. In CFT073,upaBis expressed whileupaCis transcriptionally repressed by the global regulator H-NS. In competitive colonization experiments employing the mouse UTI model, CFT073 significantly outcompeted itsupaB(but notupaC) isogenic mutant strain in the bladder. This attenuated phenotype was also observed in single-challenge experiments, where deletion of theupaBgene in CFT073 significantly reduced early colonization of the bladder.

scholarly journals A Transcriptomic Approach to the Recruitment of Venom Proteins in a Marine Annelid

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 97
Author(s):  
Ana P. Rodrigo ◽  
Ana R. Grosso ◽  
Pedro V. Baptista ◽  
Alexandra R. Fernandes ◽  
Pedro M. Costa
Keyword(s):  
Marine Invertebrates ◽  
Ecological Niches ◽  
Venomous Animals ◽  
Whole Transcriptome Sequencing ◽  
History Of ◽  
Whole Transcriptome ◽  
Animal Venoms ◽  
Venom Proteins ◽  
Phylogenetic Models

The growing number of known venomous marine invertebrates indicates that chemical warfare plays an important role in adapting to diversified ecological niches, even though it remains unclear how toxins fit into the evolutionary history of these animals. Our case study, the Polychaeta Eulalia sp., is an intertidal predator that secretes toxins. Whole-transcriptome sequencing revealed proteinaceous toxins secreted by cells in the proboscis and delivered by mucus. Toxins and accompanying enzymes promote permeabilization, coagulation impairment and the blocking of the neuromuscular activity of prey upon which the worm feeds by sucking pieces of live flesh. The main neurotoxins (“phyllotoxins”) were found to be cysteine-rich proteins, a class of substances ubiquitous among venomous animals. Some toxins were phylogenetically related to Polychaeta, Mollusca or more ancient groups, such as Cnidaria. Some toxins may have evolved from non-toxin homologs that were recruited without the reduction in molecular mass and increased specificity of other invertebrate toxins. By analyzing the phylogeny of toxin mixtures, we show that Polychaeta is uniquely positioned in the evolution of animal venoms. Indeed, the phylogenetic models of mixed or individual toxins do not follow the expected eumetazoan tree-of-life and highlight that the recruitment of gene products for a role in venom systems is complex.

scholarly journals Evolutionary pathways to antibiotic resistance are dependent upon environmental structure and bacterial lifestyle

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Alfonso Santos-Lopez ◽  
Christopher W Marshall ◽  
Michelle R Scribner ◽  
Daniel J Snyder ◽  
Vaughn S Cooper
Keyword(s):  
Antibiotic Resistance ◽  
Experimental Evolution ◽  
Drug Targets ◽  
Evolutionary Dynamics ◽  
Selective Sweeps ◽  
Resistance Level ◽  
Bacterial Populations ◽  
Collateral Sensitivity ◽  
Genetic Mechanisms ◽  
Evolution Of Resistance

Bacterial populations vary in their stress tolerance and population structure depending upon whether growth occurs in well-mixed or structured environments. We hypothesized that evolution in biofilms would generate greater genetic diversity than well-mixed environments and lead to different pathways of antibiotic resistance. We used experimental evolution and whole genome sequencing to test how the biofilm lifestyle influenced the rate, genetic mechanisms, and pleiotropic effects of resistance to ciprofloxacin in Acinetobacter baumannii populations. Both evolutionary dynamics and the identities of mutations differed between lifestyle. Planktonic populations experienced selective sweeps of mutations including the primary topoisomerase drug targets, whereas biofilm-adapted populations acquired mutations in regulators of efflux pumps. An overall trade-off between fitness and resistance level emerged, wherein biofilm-adapted clones were less resistant than planktonic but more fit in the absence of drug. However, biofilm populations developed collateral sensitivity to cephalosporins, demonstrating the clinical relevance of lifestyle on the evolution of resistance.

An integrated mosquito small RNA genomics resource reveals dynamic evolution and host responses to viruses and transposons

2020 ◽  
Author(s):  
Qicheng Ma ◽  
Satyam P. Srivastav ◽  
Stephanie Gamez ◽  
Fabiana Feitosa-Suntheimer ◽  
Edward I. Patterson ◽  
...  
Keyword(s):  
Cell Cultures ◽  
Small Rna ◽  
Evolutionary Dynamics ◽  
Expression Profiles ◽  
Mosquito Species ◽  
Mosquito Cell ◽  
Host Responses ◽  
Dna Repeats ◽  
Small Interfering Rnas ◽  
Regulatory Pathways

ABSTRACTAlthough mosquitoes are major transmission vectors for pathogenic arboviruses, viral infection has little impact on mosquito health. This immunity is due in part to mosquito RNA interference (RNAi) pathways that generate antiviral small interfering RNAs (siRNAs) and Piwi-interacting RNAs (piRNAs). RNAi also maintains genome integrity by potently repressing mosquito transposon activity in the germline and soma. However, viral and transposon small RNA regulatory pathways have not been systematically examined together in mosquitoes. Therefore, we developed an integrated Mosquito Small RNA Genomics (MSRG) resource that analyzes the transposon and virus small RNA profiles in mosquito cell cultures and somatic and gonadal tissues across four medically important mosquito species. Our resource captures both somatic and gonadal small RNA expression profiles within mosquito cell cultures, and we report the evolutionary dynamics of a novel Mosquito-Conserved piRNA Cluster Locus (MCpiRCL) composed of satellite DNA repeats. In the larger culicine mosquito genomes we detected highly regular periodicity in piRNA biogenesis patterns coinciding with the expansion of Piwi pathway genes. Finally, our resource enables detection of crosstalk between piRNA and siRNA populations in mosquito cells during a response to virus infection. The MSRG resource will aid efforts to dissect and combat the capacity of mosquitoes to tolerate and spread arboviruses.

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