Post copulatory interactions between the sexes in internally fertilizing species elicits both sexual conflict and sexual selection. Macroevolutionary and comparative studies have linked these processes to rapid transcriptomic evolution in sex-specific tissues and substantial transcriptomic post mating responses in females, patterns of which are altered when mating between reproductively isolated species. Here, we tested multiple predictions arising from sexual selection and conflict theory about the evolution of sex-specific and tissue-specific gene expression and the post mating response at the microevolutionary level.
View Article and Find Full Text PDFThe state of an animal prior to the application of a noxious stimulus can have a profound effect on their nociceptive threshold and subsequent behaviour. In mammals, the presence of acute stress preceding a painful event can have an analgesic effect whereas the presence of chronic stress can result in hyperalgesia. While considerable research has been conducted on the ability of stress to modulate mammalian responses to pain, relatively little is known about fish.
View Article and Find Full Text PDFFish are used in a variety of experimental contexts often in high numbers. To maintain their welfare and ensure valid results during invasive procedures it is vital that we can detect subtle changes in behaviour that may allow us to intervene to provide pain-relief. Therefore, an automated method, the Fish Behaviour Index (FBI), was devised and used for testing the impact of laboratory procedures and efficacy of analgesic drugs in the model species, the zebrafish.
View Article and Find Full Text PDFFish production is increasingly important to global food security. A major factor in maintaining health, productivity and welfare of farmed fish is the establishment and promotion of a stable and beneficial intestinal microbiota. Understanding the effects of factors such as host and environment on gut microbial community structure is essential for developing strategies for stimulating the establishment of a health-promoting gut-microbiota.
View Article and Find Full Text PDFSex differences in dioecious animals are pervasive and result from gene expression differences. Elevated sexual selection has been predicted to increase the number and expression of male-biased genes, and experimentally imposing monogamy on Drosophila melanogaster has led to a relative feminisation of the transcriptome. Here, we test this hypothesis further by subjecting another polyandrous species, D.
View Article and Find Full Text PDFBackground: Cryptic genetic variation (CGV) is the hidden genetic variation that can be unlocked by perturbing normal conditions. CGV can drive the emergence of novel complex phenotypes through changes in gene expression. Although our theoretical understanding of CGV has thoroughly increased over the past decade, insight into polymorphic gene expression regulation underlying CGV is scarce.
View Article and Find Full Text PDFIn conjunction with the second International Environmental Omics Symposium (iEOS) conference, held at the University of Liverpool (United Kingdom) in September 2014, a workshop was held to bring together experts in toxicology and regulatory science from academia, government and industry. The purpose of the workshop was to review the specific roles that high-content omics datasets (eg, transcriptomics, metabolomics, lipidomics, and proteomics) can hold within the adverse outcome pathway (AOP) framework for supporting ecological and human health risk assessments. In light of the growing number of examples of the application of omics data in the context of ecological risk assessment, we considered how omics datasets might continue to support the AOP framework.
View Article and Find Full Text PDFBackground: In 2014, Western Africa experienced an unanticipated explosion of Ebola virus infections. What distinguishes fatal from non-fatal outcomes remains largely unknown, yet is key to optimising personalised treatment strategies. We used transcriptome data for peripheral blood taken from infected and convalescent recovering patients to identify early stage host factors that are associated with acute illness and those that differentiate patient survival from fatality.
View Article and Find Full Text PDFAdvances in genomic and transcriptome sequencing are revealing the massive scale of previously unrecognised alterations occurring during neoplastic transformation. Breast cancers are genetically and phenotypically heterogeneous. Each of the three major subtypes [ERBB2 amplified, estrogen receptor (ESR)-positive and triple-negative] poses diagnostic and therapeutic challenges.
View Article and Find Full Text PDFThe Hawaiian strain (CB4856) of Caenorhabditis elegans is one of the most divergent from the canonical laboratory strain N2 and has been widely used in developmental, population, and evolutionary studies. To enhance the utility of the strain, we have generated a draft sequence of the CB4856 genome, exploiting a variety of resources and strategies. When compared against the N2 reference, the CB4856 genome has 327,050 single nucleotide variants (SNVs) and 79,529 insertion-deletion events that result in a total of 3.
View Article and Find Full Text PDFCrucian carp are unusual among vertebrates in surviving extended periods in the complete absence of molecular oxygen. During this time cardiac output is maintained though these mechanisms are not well understood. Using a high-density cDNA microarray, we have defined the genome-wide gene expression responses of cardiac tissue after exposing the fish at two temperatures (8 and 13 °C) to one and seven days of anoxia, followed by seven days after restoration to normoxia.
View Article and Find Full Text PDFThe identification of nucleic acid aptamers would be advanced if they could be obtained after fewer rounds of selection and amplification. In this paper the identification of bivalent aptamers for thrombin by SELEX and single-step selection are compared using next generation sequencing and motif finding informatics. Results show that similar aptamers are identified by both methods.
View Article and Find Full Text PDFOrganismal development is the most dynamic period of the life cycle, yet we have only a rough understanding of the dynamics of gene expression during adolescent transition. Here we show that adolescence in Caenorhabditis elegans is characterized by a spectacular expression shift of conserved and highly polymorphic genes. Using a high resolution time series we found that in adolescent worms over 10,000 genes changed their expression.
View Article and Find Full Text PDFChill and freeze represent very different components of low temperature stress. Whilst the principal mechanisms of tissue damage and of acquired protection from freeze-induced effects are reasonably well established, those for chill damage and protection are not. Non-freeze cold exposure (i.
View Article and Find Full Text PDFEcological speciation occurs with the adaptation of populations to different environments and concurrent evolution of reproductive isolation. Phenotypic plasticity might influence both ecological adaptation and reproductive traits. We examined environment-specific gene expression and male mating success in cactophilic Drosophila mojavensis using transcriptome sequencing.
View Article and Find Full Text PDFExtended breath-hold endurance enables the exploitation of the aquatic niche by numerous mammalian lineages and is accomplished by elevated body oxygen stores and adaptations that promote their economical use. However, little is known regarding the molecular and evolutionary underpinnings of the high muscle myoglobin concentration phenotype of divers. We used ancestral sequence reconstruction to trace the evolution of this oxygen-storing protein across a 130-species mammalian phylogeny and reveal an adaptive molecular signature of elevated myoglobin net surface charge in diving species that is mechanistically linked with maximal myoglobin concentration.
View Article and Find Full Text PDFNearly all aptamers identified so far for any given target molecule have been specific for the same binding site (epitope). The most notable exception to the 1 aptamer per target molecule rule is the pair of DNA aptamers that bind to different epitopes of thrombin. This communication refutes the suggestion that these aptamers exist because different partitioning methods were used when they were selected.
View Article and Find Full Text PDFAnthropogenic endocrine disruptors now contaminate all environments globally, with concomitant deleterious effects across diverse taxa. While most studies on endocrine disruption (ED) have focused on vertebrates, the superimposition of male sexual characteristics in the female dogwhelk, Nucella lapillus (imposex), caused by organotins, provides one of the most clearcut ecological examples of anthropogenically induced ED in aquatic ecosystems. To identify the underpinning mechanisms of imposex for this 'nonmodel' species, we combined Roche 454 pyrosequencing with custom oligoarray fabrication inexpensively to both generate gene models and identify those responding to chronic tributyltin (TBT) treatment.
View Article and Find Full Text PDFBackground: Hypoxic vasodilation is a physiological response to low oxygen tension that increases blood supply to match metabolic demands. Although this response has been characterized for >100 years, the underlying hypoxic sensing and effector signaling mechanisms remain uncertain. We have shown that deoxygenated myoglobin in the heart can reduce nitrite to nitric oxide (NO·) and thereby contribute to cardiomyocyte NO· signaling during ischemia.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
March 2012
Because of a recent whole genome duplication, the hypoxia-tolerant common carp and goldfish are the only vertebrates known to possess two myoglobin (Mb) paralogs. One of these, Mb1, occurs in oxidative muscle but also in several other tissues, including capillary endothelial cells, whereas the other, Mb2, is a unique isoform specific to brain neurons. To help understand the functional roles of these diverged isoforms in the tolerance to severe hypoxia in the carp, we have compared their O(2) equilibria, carbon monoxide (CO) and O(2) binding kinetics, thiol S-nitrosation, nitrite reductase activities, and peroxidase activities.
View Article and Find Full Text PDFCurrent aquatic chemical testing guidelines recognize that solvents can potentially interfere with the organism or environmental conditions of aquatic ecotoxicity tests and therefore recommend concentration limits for their use. These recommendations are based on evidence of adverse solvent effects in apical level tests. The growing importance of subapical and chronic endpoints in future test strategies, however, suggests that the limits may need reassessment.
View Article and Find Full Text PDFIn 2000, fishermen reported the appearance of deformed reproductive organs in whitefish (Coregonus spp.) from Lake Thun, Switzerland. Despite intensive investigations, the causes of these abnormalities remain unknown.
View Article and Find Full Text PDFTheoretical and empirical studies have sought to explain the formation and maintenance of social relationships within groups. The resulting dominance hierarchies have significant fitness and survival consequences dependent upon social status. We hypothesised that each position or rank within a group has a distinctive brain gene expression profile that correlates with behavioural phenotype.
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