Do the Offspring of Sex Reversals Have Higher Sensitivity to Environmental Perturbations?

2021 ◽  
pp. 1-14
Author(s):  
Francesc Piferrer ◽  
Dafni Anastasiadi
Keyword(s):  
Sex Determination ◽  
Molecular Mechanisms ◽  
Global Climate ◽  
Sex Reversal ◽  
Environmental Cues ◽  
Environmental Sex Determination ◽  
Future Studies ◽  
Genome Data ◽  
Environmental Perturbations ◽  
Higher Sensitivity

Sex determination systems in vertebrates vary along a continuum from genetic (GSD) to environmental sex determination (ESD). Individuals that show a sexual phenotype opposite to their genotypic sex are called sex reversals. Aside from genetic elements, temperature, sex steroids, and exogenous chemicals are common factors triggering sex reversal, a phenomenon that may occur even in strict GSD species. In this paper, we review the literature on instances of sex reversal in fish, amphibians, reptiles, birds, and mammals. We focus on the offspring of sex-reversed parents in the instances that they can be produced, and show that in all cases studied the offspring of these sex-reversed parents exhibit a higher sensitivity to environmental perturbations than the offspring of non-sex-reversed parents. We suggest that the inheritance of this sensitivity, aside from possible genetic factors, is likely to be mediated by epigenetic mechanisms such as DNA methylation, since these mechanisms are responsive to environmental cues, and epigenetic modifications can be transmitted to the subsequent generations. Species with a chromosomal GSD system with environmental sensitivity and availability of genetic sex markers should be employed to further test whether offspring of sex-reversed parents have greater sensitivity to environmental perturbations. Future studies could also benefit from detailed whole-genome data in order to elucidate the underlying molecular mechanisms. Finally, we discuss the consequences of such higher sensitivity in the context of global climate change.

scholarly journals Temperature-Induced Sex Reversal in Reptiles: Prevalence, Discovery, and Evolutionary Implications

2021 ◽  
pp. 1-9
Author(s):  
Sarah L. Whiteley ◽  
Meghan A. Castelli ◽  
Duminda S.B. Dissanayake ◽  
Clare E. Holleley ◽  
Arthur Georges
Keyword(s):  
Sex Determination ◽  
Molecular Mechanisms ◽  
Sex Reversal ◽  
Future Research ◽  
Wild Populations ◽  
Changing Climate ◽  
In The Wild ◽  
Low Incidence ◽  
Thermal Influence ◽  
Genetically Determined

Sex reversal is the process by which an individual develops a phenotypic sex that is discordant with its chromosomal or genotypic sex. It occurs in many lineages of ectothermic vertebrates, such as fish, amphibians, and at least one agamid and one scincid reptile species. Sex reversal is usually triggered by an environmental cue that alters the genetically determined process of sexual differentiation, but it can also be caused by exposure to exogenous chemicals, hormones, or pollutants. Despite the occurrence of both temperature-dependent sex determination (TSD) and genetic sex determination (GSD) broadly among reptiles, only 2 species of squamates have thus far been demonstrated to possess sex reversal in nature (GSD with overriding thermal influence). The lack of species with unambiguously identified sex reversal is not necessarily a reflection of a low incidence of this trait among reptiles. Indeed, sex reversal may be relatively common in reptiles, but little is known of its prevalence, the mechanisms by which it occurs, or the consequences of sex reversal for species in the wild under a changing climate. In this review, we present a roadmap to the discovery of sex reversal in reptiles, outlining the various techniques that allow new occurrences of sex reversal to be identified, the molecular mechanisms that may be involved in sex reversal and how to identify them, and approaches for assessing the impacts of sex reversal in wild populations. We discuss the evolutionary implications of sex reversal and use the central bearded dragon (<i>Pogona vitticeps</i>) and the eastern three-lined skink (<i>Bassiana duperreyi</i>) as examples of how species with opposing patterns of sex reversal may be impacted differently by our rapidly changing climate. Ultimately, this review serves to highlight the importance of understanding sex reversal both in the laboratory and in wild populations and proposes practical solutions to foster future research.

scholarly journals Multiple Geographical Origins of Environmental Sex Determination enhanced the diversification of Darwin’s Favourite Orchids

2017 ◽  
Author(s):  
Oscar Alejandro Pérez-Escobar ◽  
Guillaume Chomicki ◽  
Fabien L. Condamine ◽  
Jurriaan M. de Vos ◽  
Aline C. Martins ◽  
...  
Keyword(s):  
Sex Determination ◽  
Mating Systems ◽  
Driving Forces ◽  
Environmental Cues ◽  
Sexual System ◽  
Environmental Sex Determination ◽  
Diversification Rates ◽  
Sexual Systems ◽  
Alternative Systems ◽  
Phylogenetic Framework

AbstractEnvironmental sex determination (ESD) – a change in sexual function during an individual life span driven by environmental cues – is an exceedingly rare sexual system among angiosperms. Because ESD can directly affect reproduction success, it could influence diversification rate as compared with lineages that have alternative mating systems. Here we test this hypothesis using a solid phylogenetic framework of Neotropical Catasetinae, the angiosperm lineage richest in taxa with ESD. We assess whether gains of ESD are associated with higher diversification rates compared to lineages with alternative systems while considering additional traits known to positively affect diversification rates in orchids. We found that ESD has evolved asynchronously three times during the last ~5 Myr. Lineages with ESD have consistently higher diversification rates than related lineages with other sexual systems. Habitat fragmentation due to mega-wetlands extinction, and climate instability are suggested as the driving forces for ESD evolution.

scholarly journals Evolutionary and demographic consequences of temperature-induced masculinization under climate warming: the effects of mate choice

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Edina Nemesházi ◽  
Szilvia Kövér ◽  
Veronika Bókony
Keyword(s):  
Climate Change ◽  
Mate Choice ◽  
Sex Determination ◽  
Climate Warming ◽  
Sex Chromosome ◽  
Global Climate ◽  
Sex Ratios ◽  
Sex Reversal ◽  
Phenotypic Traits ◽  
System Transformation

Abstract Background One of the dangers of global climate change to wildlife is distorting sex ratios by temperature-induced sex reversals in populations where sex determination is not exclusively genetic, potentially leading to population collapse and/or sex-determination system transformation. Here we introduce a new concept on how these outcomes may be altered by mate choice if sex-chromosome-linked phenotypic traits allow females to choose between normal and sex-reversed (genetically female) males. Results We developed a theoretical model to investigate if an already existing autosomal allele encoding preference for sex-reversed males would spread and affect demographic and evolutionary processes under climate warming. We found that preference for sex-reversed males (1) more likely spread in ZW/ZZ than in XX/XY sex-determination systems, (2) in populations starting with ZW/ZZ system, it significantly hastened the transitions between different sex-determination systems and maintained more balanced adult sex ratio for longer compared to populations where all females preferred normal males; and (3) in ZW/ZZ systems with low but non-zero viability of WW individuals, a widespread preference for sex-reversed males saved the populations from early extinction. Conclusions Our results suggest that climate change may affect the evolution of mate choice, which in turn may influence the evolution of sex-determination systems, sex ratios, and thereby adaptive potential and population persistence. These findings show that preferences for sex-linked traits have special implications in species with sex reversal, highlighting the need for empirical research on the role of sex reversal in mate choice.

scholarly journals Metabolism and Sex Differentiation in Animals from a Starvation Perspective

2021 ◽  
pp. 1-11
Author(s):  
Yuta Sakae ◽  
Minoru Tanaka
Keyword(s):  
Sex Determination ◽  
Environmental Changes ◽  
Sex Differentiation ◽  
Green Light ◽  
Acid Synthesis ◽  
Sex Reversal ◽  
Environmental Sex Determination ◽  
Biological Factors ◽  
Signal Transducers ◽  
Male Sex

Animals determine their sex genetically (GSD: genetic sex determination) and/or environmentally (ESD: environmental sex determination). Medaka (<i>Oryzias latipes</i>) employ a XX/XY GSD system, however, they display female-to-male sex reversal in response to various environmental changes such as temperature, hypoxia, and green light. Interestingly, we found that 5 days of starvation during sex differentiation caused female-to-male sex reversal. In this situation, the metabolism of pantothenate and fatty acid synthesis plays an important role in sex reversal. Metabolism is associated with other biological factors such as germ cells, HPG axis, lipids, and epigenetics, and supplys substances and acts as signal transducers. In this review, we discuss the importance of metabolism during sex differentiation and how metabolism contributes to sex differentiation.

Mesophyll conductance: the leaf corridors for photosynthesis

2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Main Role ◽  
Mesophyll Conductance ◽  
Future Studies ◽  
Cell Structures ◽  
Leaf Tissues ◽  
Change Framework ◽  
Chloroplast Stroma

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.

scholarly journals The Power of Yeast in Modelling Human Nuclear Mutations Associated with Mitochondrial Diseases

Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 300
Author(s):  
Camilla Ceccatelli Berti ◽  
Giulia di Punzio ◽  
Cristina Dallabona ◽  
Enrico Baruffini ◽  
Paola Goffrini ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Mitochondrial Diseases ◽  
Yeast Saccharomyces Cerevisiae ◽  
Genome Data ◽  
New Genes ◽  
Eukaryotic Organism ◽  
Novel Variants ◽  
Therapeutic Molecules ◽  
Nuclear Mutations

The increasing application of next generation sequencing approaches to the analysis of human exome and whole genome data has enabled the identification of novel variants and new genes involved in mitochondrial diseases. The ability of surviving in the absence of oxidative phosphorylation (OXPHOS) and mitochondrial genome makes the yeast Saccharomyces cerevisiae an excellent model system for investigating the role of these new variants in mitochondrial-related conditions and dissecting the molecular mechanisms associated with these diseases. The aim of this review was to highlight the main advantages offered by this model for the study of mitochondrial diseases, from the validation and characterisation of novel mutations to the dissection of the role played by genes in mitochondrial functionality and the discovery of potential therapeutic molecules. The review also provides a summary of the main contributions to the understanding of mitochondrial diseases emerged from the study of this simple eukaryotic organism.

scholarly journals Sex Ratios in a Warming World: Thermal Effects on Sex-Biased Survival, Sex Determination, and Sex Reversal

2021 ◽  
Vol 112 (2) ◽  
pp. 155-164
Author(s):  
Suzanne Edmands
Keyword(s):  
High Temperature ◽  
Sex Ratio ◽  
Sex Determination ◽  
Heat Tolerance ◽  
Sex Ratios ◽  
Sex Reversal ◽  
Survival Sex ◽  
Ratio Distortion ◽  
Warming World ◽  
Sex Ratio Distortion

Abstract Rising global temperatures threaten to disrupt population sex ratios, which can in turn cause mate shortages, reduce population growth and adaptive potential, and increase extinction risk, particularly when ratios are male biased. Sex ratio distortion can then have cascading effects across other species and even ecosystems. Our understanding of the problem is limited by how often studies measure temperature effects in both sexes. To address this, the current review surveyed 194 published studies of heat tolerance, finding that the majority did not even mention the sex of the individuals used, with &lt;10% reporting results for males and females separately. Although the data are incomplete, this review assessed phylogenetic patterns of thermally induced sex ratio bias for 3 different mechanisms: sex-biased heat tolerance, temperature-dependent sex determination (TSD), and temperature-induced sex reversal. For sex-biased heat tolerance, documented examples span a large taxonomic range including arthropods, chordates, protists, and plants. Here, superior heat tolerance is more common in females than males, but the direction of tolerance appears to be phylogenetically fluid, perhaps due to the large number of contributing factors. For TSD, well-documented examples are limited to reptiles, where high temperature usually favors females, and fishes, where high temperature consistently favors males. For temperature-induced sex reversal, unambiguous cases are again limited to vertebrates, and high temperature usually favors males in fishes and amphibians, with mixed effects in reptiles. There is urgent need for further work on the full taxonomic extent of temperature-induced sex ratio distortion, including joint effects of the multiple contributing mechanisms.

Sign in / Sign up

Export Citation Format

Share Document