Assessing the role of mitonuclear interactions on mitochondrial function and organismal fitness in natural populations.

Mitochondrial function depends on the effective interactions between proteins and RNA encoded by the mitochondrial and nuclear genomes. Evidence suggests that both genomes respond to thermal selection and promote adaptation. However, the contribution of their epistatic interactions to life history phenotypes in the wild remains elusive.

Accelerated differentiation of neo-W nuclear-encoded mitochondrial genes between two climate-associated bird lineages signals potential co-evolution with mitogenomes.

There is considerable evidence for mitochondrial-nuclear co-adaptation as a key evolutionary driver. Hypotheses regarding the roles of sex-linkage have emphasized Z-linked nuclear genes with mitochondrial function (N-mt genes), whereas it remains contentious whether the perfect co-inheritance of W genes with mitogenomes could hinder or facilitate co-adaptation. Young (neo-) sex chromosomes that possess relatively many N-mt genes compared to older chromosomes provide unprecedented hypothesis-testing opportunities.

Sexual Selection Increases Male Behavioral Consistency in .

AbstractSexual selection has been suggested to influence the expression of male behavioral consistency. However, despite predictions, direct experimental support for this hypothesis has been lacking. Here, we investigated whether sexual selection altered male behavioral consistency in -a species with both pre- and postcopulatory sexual selection.

Sex-specific transgenerational effects of diet on offspring life history and physiology.

Dietary variation in males and females can shape the expression of offspring life histories and physiology. However, the relative contributions of maternal and paternal dietary variation to phenotypic expression of latter generations is currently unknown. We provided male and female grandparents with diets differing in sucrose concentration prior to reproduction, and similarly subjected their grandoffspring to the same treatments.

Eosinophilic oesophagitis: a common cause of food bolus obstruction.

Background: Eosinophilic oesophagitis (EOE) is a known cause of food bolus obstruction (FBO) with rising incidence and prevalence.

Aims: To assess the rates of EOE in adult cases presenting with an FBO via prospective biopsy collection during index endoscopy.

Methods: Oesophageal FBO cases requiring gastroscopy between February 2014 and January 2021 at a single institution with a unified policy to perform biopsies on FBO cases were analysed using medical records, endoscopy and histology.

Mitochondrial genetic variation as a potential mediator of intraspecific behavioural diversity.

Mitochondrial genes play an essential role in energy metabolism. Variation in the mitochondrial DNA (mtDNA) sequence often exists within species, and this variation can have consequences for energy production and organismal life history. Yet, despite potential links between energy metabolism and the expression of animal behaviour, mtDNA variation has been largely neglected to date in studies investigating intraspecific behavioural diversity.

Mitonuclear interactions shape both direct and parental effects of diet on fitness and involve a SNP in mitoribosomal 16s rRNA.

Nutrition is a primary determinant of health, but responses to nutrition vary with genotype. Epistasis between mitochondrial and nuclear genomes may cause some of this variation, but which mitochondrial loci and nutrients participate in complex gene-by-gene-by-diet interactions? Furthermore, it remains unknown whether mitonuclear epistasis is involved only in the immediate responses to changes in diet, or whether mitonuclear genotype might modulate sensitivity to variation in parental nutrition, to shape intergenerational fitness responses. Here, in Drosophila melanogaster, we show that mitonuclear epistasis shapes fitness responses to variation in dietary lipids and amino acids.

Temperature change exerts sex-specific effects on behavioural variation.

Temperature is a key factor mediating organismal fitness and has important consequences for species' ecology. While the mean effects of temperature on behaviour have been well-documented in ectotherms, how temperature alters behavioural variation among and within individuals, and whether this differs between the sexes, remains unclear. Such effects likely have ecological and evolutionary consequences, given that selection acts at the individual level.

Evolutionary genetics of the mitochondrial genome: insights from Drosophila.

Mitochondria are key to energy conversion in virtually all eukaryotes. Intriguingly, despite billions of years of evolution inside the eukaryote, mitochondria have retained their own small set of genes involved in the regulation of oxidative phosphorylation (OXPHOS) and protein translation. Although there was a long-standing assumption that the genetic variation found within the mitochondria would be selectively neutral, research over the past 3 decades has challenged this assumption.

Y chromosome-linked variation affects locomotor activity in male Drosophila melanogaster and is robust to differences in thermal environment.

Although containing genes important for sex determination, genetic variation within the Y chromosome was traditionally predicted to contribute little to the expression of sexually dimorphic traits. This prediction was shaped by the assumption that the chromosome harbours few protein-coding genes, and that capacity for Y-linked variation to shape adaptation would be hindered by the chromosome's lack of recombination and holandric inheritance. Consequently, most studies exploring the genotypic contributions to sexually dimorphic traits have focused on the autosomes and X chromosome.

Effects of mitochondrial haplotype on pre-copulatory mating success in male fruit flies (Drosophila melanogaster).

While mitochondria have long been understood to be critical to cellular function, questions remain as to how genetic variation within mitochondria may underlie variation in general metrics of organismal function. To date, studies investigating links between mitochondrial genotype and phenotype have largely focused on differences in expression of genes and physiological and life-history traits across haplotypes. Mating display behaviours may also be sensitive to mitochondrial functionality and so may also be affected by sequence variation in mitochondrial DNA, with consequences for sexual selection and fitness.

New Insights into Mitochondrial-Nuclear Interactions Revealed through Analysis of Small RNAs.

Mitochondrial sequence variants affect phenotypic function, often through interaction with the nuclear genome. These "mitonuclear" interactions have been linked both to evolutionary processes and human health. The study of these interactions has focused on mechanisms regulating communication between mitochondrial and nuclear proteins; the role of mitochondrial (mt) RNAs has received little attention.

Fragmentation in mitochondrial genomes in relation to elevated sequence divergence and extreme rearrangements.

Background: A single circular mitochondrial (mt) genome is a common feature across most metazoans. The mt-genome includes protein-coding genes involved in oxidative phosphorylation, as well as RNAs necessary for translation of mt-RNAs, whose order and number are highly conserved across animal clades, with few known exceptions of alternative mt-gene order or mt-genome architectures. One such exception consists of the fragmented mitochondrial genome, a type of genome architecture where mt-genes are split across two or more mt-chromosomes.

Selection for biparental inheritance of mitochondria under hybridization and mitonuclear fitness interactions.

Uniparental inheritance (UPI) of mitochondria predominates over biparental inheritance (BPI) in most eukaryotes. However, examples of BPI of mitochondria, or paternal leakage, are becoming increasingly prevalent. Most reported cases of BPI occur in hybrids of distantly related sub-populations.

A neuroendocrine cause for refractory symptoms in coeliac disease.

Neuroendocrine tumours while rare, need to be considered in patients with chronic diarrhoea. Reported herein is a case of vasoactive intestinal peptideoma in a patient with refractory diarrhoea following a diagnosis of coeliac disease.

Small mitochondrial RNAs as mediators of nuclear gene regulation, and potential implications for human health.

Much research has focused on the effects of pathogenic mitochondrial mutations on health. Notwithstanding, the mechanisms regulating the link between these mutations and their effects remain elusive in several cases. Here, we propose that certain mitochondrial mutations may disrupt function of a set of mitochondrial-transcribed small RNAs, perturbing communication between mitochondria and nucleus, leading to disease.

A Single Educational Intervention Improves Pregnancy-Related Knowledge and Emotional Health Among Women With IBD Who Are Pregnant or Wish to Conceive.

Background: There is considerable interest in improving the education and care of women with inflammatory bowel disease (IBD) to improve pregnancy outcomes. Despite increased awareness, not all women with IBD have access to pregnancy-related education and the quality of counseling is variable. We aimed to assess the effectiveness of a simple educational intervention for improving pregnancy-related knowledge and to evaluate the effect of education on patient outcomes including anxiety, depression, and quality of life in women with IBD.

Sexually antagonistic evolution of mitochondrial and nuclear linkage.

Across eukaryotes, genes encoding bioenergetic machinery are located in both mitochondrial and nuclear DNA, and incompatibilities between the two genomes can be devastating. Mitochondria are often inherited maternally, and theory predicts sex-specific fitness effects of mitochondrial mutational diversity. Yet how evolution acts on linkage patterns between mitochondrial and nuclear genomes is poorly understood.

Integrating Mitochondrial Aerobic Metabolism into Ecology and Evolution.

Biologists have long appreciated the critical role that energy turnover plays in understanding variation in performance and fitness among individuals. Whole-organism metabolic studies have provided key insights into fundamental ecological and evolutionary processes. However, constraints operating at subcellular levels, such as those operating within the mitochondria, can also play important roles in optimizing metabolism over different energetic demands and time scales.

Infliximab, adalimumab and vedolizumab concentrations across pregnancy and vedolizumab concentrations in infants following intrauterine exposure.

Background: The impact of pregnancy on levels of biologic agents in patients with IBD is undefined and time to elimination in vedolizumab-exposed infants is unknown.

Aims: To determine the effect of pregnancy on infliximab, adalimumab and vedolizumab levels and to study infant vedolizumab clearance METHODS: In a prospective observational study, maternal drug levels were measured pre-conception, in each trimester, at delivery and postpartum. The association between drug levels and gestation in weeks was assessed using generalised estimating equation modelling.

Sibling rivalry versus mother's curse: can kin competition facilitate a response to selection on male mitochondria?

Assuming that fathers never transmit mitochondrial DNA (mtDNA) to their offspring, mitochondrial mutations that affect male fitness are invisible to direct selection on males, leading to an accumulation of male-harming alleles in the mitochondrial genome (mother's curse). However, male phenotypes encoded by mtDNA can still undergo adaptation via kin selection provided that males interact with females carrying related mtDNA, such as their sisters. Here, using experiments with carrying standardized nuclear DNA but distinct mitochondrial DNA, we test whether the mitochondrial haplotype carried by interacting pairs of larvae affects survival to adulthood, as well as the fitness of the adults.

Controlling for body size leads to inferential biases in the biological sciences.

Many traits correlate with body size. Studies that seek to uncover the ecological factors that drive evolutionary responses in traits typically examine these responses relative to associated changes in body size using multiple regression analysis. However, it is not well appreciated that in the presence of strongly correlated variables, the partial (i.