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Science Advances Feb 2022The shift from sexual reproduction to parthenogenesis has occurred repeatedly in animals, but how the loss of sex affects genome evolution remains poorly understood. We...
The shift from sexual reproduction to parthenogenesis has occurred repeatedly in animals, but how the loss of sex affects genome evolution remains poorly understood. We generated reference genomes for five independently evolved parthenogenetic species in the stick insect genus and their closest sexual relatives. Using these references and population genomic data, we show that parthenogenesis results in an extreme reduction of heterozygosity and often leads to genetically uniform populations. We also find evidence for less effective positive selection in parthenogenetic species, suggesting that sex is ubiquitous in natural populations because it facilitates fast rates of adaptation. Parthenogenetic species did not show increased transposable element (TE) accumulation, likely because there is little TE activity in the genus. By using replicated sexual-parthenogenetic comparisons, our study reveals how the absence of sex affects genome evolution in natural populations, providing empirical support for the negative consequences of parthenogenesis as predicted by theory.
Topics: Animals; DNA Transposable Elements; Genome, Insect; Insecta; Neoptera; Parthenogenesis; Reproduction
PubMed: 35196080
DOI: 10.1126/sciadv.abg3842 -
International Journal of Molecular... Aug 2021Parthenogenetic embryos have been widely studied as an effective tool related to paternal and maternal imprinting genes and reproductive problems for a long time. In...
Parthenogenetic embryos have been widely studied as an effective tool related to paternal and maternal imprinting genes and reproductive problems for a long time. In this study, we established a parthenogenetic epiblast-like stem cell line through culturing parthenogenetic diploid blastocysts in a chemically defined medium containing activin A and bFGF named paAFSCs. The paAFSCs expressed pluripotent marker genes and germ-layer-related genes, as well as being alkaline-phosphatase-positive, which is similar to epiblast stem cells (EpiSCs). We previously showed that advanced embryonic stem cells (ASCs) represent hypermethylated naive pluripotent embryonic stem cells (ESCs). Here, we converted paAFSCs to ASCs by replacing bFGF with bone morphogenetic protein 4 (BMP4), CHIR99021, and leukemia inhibitory factor (LIF) in a culture medium, and we obtained parthenogenetic advanced stem cells (paASCs). The paASCs showed similar morphology with ESCs and also displayed a stronger developmental potential than paAFSCs in vivo by producing chimaeras. Our study demonstrates that maternal genes could support parthenogenetic EpiSCs derived from blastocysts and also have the potential to convert primed state paAFSCs to naive state paASCs.
Topics: Activins; Animals; Blastocyst; Bone Morphogenetic Protein 4; Cell Culture Techniques; Cell Differentiation; DNA Methylation; Embryo Culture Techniques; Embryonic Stem Cells; Female; Fibroblast Growth Factors; Germ Layers; Leukemia Inhibitory Factor; Mice; Mice, 129 Strain; Mice, Inbred ICR; Mouse Embryonic Stem Cells; Parthenogenesis; Pluripotent Stem Cells
PubMed: 34445681
DOI: 10.3390/ijms22168976 -
Bioethics Sep 2021In a recent article Thomas Douglas and Katrien Devolder propose a theory of genetic parenthood according to which a human child can have only two genetic human parents....
In a recent article Thomas Douglas and Katrien Devolder propose a theory of genetic parenthood according to which a human child can have only two genetic human parents. I argue this theory is arbitrarily narrow and fails to account for cases such as hybrids, cloning, chimerism, twinning, parthenogenesis, mitochondrial replacement techniques, and more. I propose an alternate theory of genetic parenthood, one that is prima facie consistent with our commonsense intuitions about genetic parenthood and relevant to a right to procreative autonomy.
Topics: Child; Cloning, Organism; Humans; Parents; Reproduction; Reproductive Techniques, Assisted
PubMed: 34128235
DOI: 10.1111/bioe.12901 -
Current Opinion in Insect Science Apr 2023Endosymbionts are maternally transmitted, and therefore benefit from maximizing female offspring numbers. Parthenogenesis-induction (PI) is the most effective type of... (Review)
Review
Endosymbionts are maternally transmitted, and therefore benefit from maximizing female offspring numbers. Parthenogenesis-induction (PI) is the most effective type of manipulation for transmission, but has solely been detected in haplodiploid species, whereas cytoplasmic incompatibility (CI) is detected frequently across the arthropod phylum, including haplodiploids. This puzzling observation led us to hypothesize that the molecular sex-determination mechanism of the haplodiploid host may be a constraining factor in the ability of endosymbionts to induce parthenogenesis. Recent insights indicate that PI-endosymbionts may be able to directly manipulate sex-determination genes to induce the necessary steps required for PI in haplodiploids. However, sex-determination cascades vary extensively, so PI-induction would require a specialized and host-dependent tool set. Contrastingly, CI-related genes target conserved cell-cycle mechanisms, are located on mobile elements, and spread easily. Finally, endosymbiont-manipulations may have a strong impact on the effectiveness of haplodiploid biocontrol agents, but can also be used to enhance their efficacy.
Topics: Animals; Female; Parthenogenesis; Wolbachia; Arthropods; Sex Determination Processes
PubMed: 36958587
DOI: 10.1016/j.cois.2023.101023 -
Frontiers in Cell and Developmental... 2022The cladoceran crustacean produces only females by parthenogenesis in a healthy population. However, in response to environmental declines such as crowding and lack of... (Review)
Review
The cladoceran crustacean produces only females by parthenogenesis in a healthy population. However, in response to environmental declines such as crowding and lack of foods, it produces eggs destined to become males that are genetically identical to females. During the development of the sexually committed eggs, DM domain-containing transcription factor () orchestrates male trait formation globally both in somatic and gonadal tissues. Recent studies have revealed that expression is tightly controlled at transcriptional, post-transcriptional, and epigenetic levels to avoid sexual ambiguity. In this review, together with basic information on structure and expression, we introduce the multi-layered regulation and discuss how each regulation is interconnected for controlling male development in environmental sex-determining .
PubMed: 35493103
DOI: 10.3389/fcell.2022.881255 -
Journal of Phycology Jun 2021Monoecy and parthenogenesis exist in certain male and female gametophytes of the brown alga Undaria pinnatifida. The inheritance of these traits is not known. In this...
The Inheritable Characteristics of Monoecy and Parthenogenesis Provide A Means for Establishing A Doubled Haploid Population in the Economically Important Brown Alga Undaria pinnatifida (Laminariales, Alariaceae).
Monoecy and parthenogenesis exist in certain male and female gametophytes of the brown alga Undaria pinnatifida. The inheritance of these traits is not known. In this study, we made a cross between a male and a female gametophyte clone which could exhibit monoecy and parthenogenesis phenotypes, respectively, and obtained their next-generation gametophyte offspring. We found that under conditions suitable for gametogenesis, all of the male offspring (n = 100) exhibited monoecy phenotype and all of the female offspring (n = 100) only formed oogonia and underwent parthenogenesis, suggesting that monoecy and parthenogenesis phenotypes are inheritable. Then, we established a doubled haploid (DH) population through monoecious selfing and parthenogenesis, and evaluated the young sporophyte growth and the maximum quantum yield (F /F ) of 10 "male" and 10 "female" DH lines. On day 60, the average length of the "male" DH lines was significantly larger than that of the "female" DH lines, while their average F /F values were not significantly different. Monoecious selfing seemed superior to parthenogenesis as the sporophyte formation efficiency, and the young sporophyte growth was better in the former than in the latter. We also crossed two monoecious gametophytes with another male gametophyte, and a parentage analysis showed success of obtaining hybrid sporophytes, indicating that the female gametes released by the monoecious gametophyte can actually be fertilized by sperm. The approach of establishing a DH population proposed here will be useful in genetic breeding and quantitative trait loci mapping in U. pinnatifida and may be applicable to other kelp species.
Topics: Haploidy; Kelp; Parthenogenesis; Phaeophyceae; Undaria
PubMed: 33624318
DOI: 10.1111/jpy.13153 -
Journal of Assisted Reproduction and... Jul 2023Despite the success of ICSI in treating severe male factor infertile patients, total fertilization failure (FF) still occurs in around 1-3% of ICSI cycles. To overcome...
Significant differences in efficiency between two commonly used ionophore solutions for assisted oocyte activation (AOA): a prospective comparison of ionomycin and A23187.
PURPOSE
Despite the success of ICSI in treating severe male factor infertile patients, total fertilization failure (FF) still occurs in around 1-3% of ICSI cycles. To overcome FF, the use of calcium ionophores has been proposed to induce oocyte activation and restore fertilization rates. However, assisted oocyte activation (AOA) protocols and ionophores vary between laboratories, and the morphokinetic development underlying AOA remains understudied.
METHODS
A prospective single-center cohort study involving 81 in vitro matured metaphase-II oocytes from 66 oocyte donation cycles artificially activated by A23187 (GM508 CultActive, Gynemed) (n=42) or ionomycin (n=39). Parthenogenesis was induced, and morphokinetic parameters (tPNa, tPNf, t2-t8, tSB, and tB) were compared between the 2 study groups and a control group comprising 39 2PN-zygotes from standard ICSI cycles.
RESULTS
Ionomycin treatment resulted in higher activation rates compared to A23187 (38.5% vs 23.8%, p=0.15). Importantly, none of the A23187-activated parthenotes formed blastocysts. When evaluating the morphokinetic dynamics between the two ionophores, we found that tPNa and tPNf were significantly delayed in the group treated by A23187 (11.84 vs 5.31, p=0.002 and 50.15 vs 29.69, p=0.005, respectively). t2 was significantly delayed in A23187-activated parthenotes when compared to the double heterologous control embryo group. In contrast, the morphokinetic development of ionomycin-activated parthenotes was comparable to control embryos (p>0.05).
CONCLUSION
Our results suggest that A23187 leads to lower oocyte activation rates and profoundly affects morphokinetic timings and preimplantation development in parthenotes. Despite our limited sample size and low parthenote competence, standardization and further optimization of AOA protocols may allow wider use and improved outcomes for FF cycles.
Topics: Male; Animals; Ionomycin; Ionophores; Calcimycin; Cohort Studies; Sperm Injections, Intracytoplasmic; Oocytes
PubMed: 37247099
DOI: 10.1007/s10815-023-02833-9 -
The New Phytologist Jan 2021Sex expression of homosporous ferns is controlled by multiple factors, one being the antheridiogen system. Antheridiogens are pheromones released by sexually mature... (Review)
Review
Sex expression of homosporous ferns is controlled by multiple factors, one being the antheridiogen system. Antheridiogens are pheromones released by sexually mature female fern gametophytes, turning nearby asexual gametophytes precociously male. Nevertheless, not all species respond. It is still unknown how many fern species use antheridiogens, how the antheridiogen system evolved, and whether it is affected by polyploidy and/or apomixis. We tested the response of 68 fern species to antheridiogens in cultivation. These results were combined with a comprehensive review of literature to form the largest dataset of antheridiogen interactions to date. Analyzed species also were coded as apomictic or sexual and diploid or polyploid. Our final dataset contains a total of 498 interactions involving 208 species (c. 2% of all ferns). About 65% of studied species respond to antheridiogen. Multiple antheridiogen types were delimited and their evolution is discussed. Antheridiogen responsiveness was not significantly affected by apomixis or polyploidy. Antheridiogens are widely used by ferns to direct sex expression. The antheridiogen system likely evolved multiple times and provides homosporous ferns with the benefits often associated with heterospory, such as increased rates of outcrossing. Despite expectations, antheridiogens may be beneficial to polyploids and apomicts.
Topics: Apomixis; Diploidy; Ferns; Germ Cells, Plant; Polyploidy
PubMed: 32740926
DOI: 10.1111/nph.16836 -
The Journal of Heredity Mar 2021Studying alternative forms of reproduction in natural populations is of fundamental importance for understanding the costs and benefits of sex. Mayflies are one of the...
Studying alternative forms of reproduction in natural populations is of fundamental importance for understanding the costs and benefits of sex. Mayflies are one of the few animal groups where sexual reproduction co-occurs with different types of parthenogenesis, providing ideal conditions for identifying benefits of sex in natural populations. Here, we establish a catalog of all known mayfly species capable of reproducing by parthenogenesis, as well as species unable to do so. Overall, 1.8% of the described species reproduce parthenogenetically, which is an order of magnitude higher than reported in other animal groups. This frequency even reaches 47.8% if estimates are based on the number of studied rather than described mayfly species, as reproductive modes have thus far been studied in only 17 out of 42 families. We find that sex is a more successful strategy than parthenogenesis (associated with a higher hatching success of eggs), with a trade-off between the hatching success of parthenogenetic and sexual eggs. This means that improving the capacity for parthenogenesis may come at a cost for sexual reproduction. Such a trade-off can help explain why facultative parthenogenesis is extremely rare among animals despite its potential to combine the benefits of sexual and parthenogenetic reproduction. We argue that parthenogenesis is frequently selected in mayflies in spite of this probable trade-off because their typically low dispersal ability and short and fragile adult life may frequently generate situations of mate limitation in females. Mayflies are currently clearly underappreciated for understanding the benefits of sex under natural conditions.
Topics: Animals; Ephemeroptera; Female; Male; Parthenogenesis; Sex Ratio
PubMed: 32918457
DOI: 10.1093/jhered/esaa027 -
Genes Jul 2020Apomixis (agamospermy) is asexual reproduction by seed. In angiosperms it represents an easy byway of life cycle renewal through gamete-like cells that give rise to... (Review)
Review
Apomixis (agamospermy) is asexual reproduction by seed. In angiosperms it represents an easy byway of life cycle renewal through gamete-like cells that give rise to maternal embryos without ploidy reduction (meiosis) and ploidy restitution (syngamy). The origin of apomixis still represents an unsolved problem, as it may be either evolved from sex or the other way around. This review deals with a reappraisal of the origin of apomixis in order to deepen knowledge on such asexual mode of reproduction which seems mainly lacking in the most basal angiosperm orders (i.e., Amborellales, Nymphaeales and Austrobaileyales, also known as ANA-grade), while it clearly occurs in different forms and variants in many unrelated families of monocots and eudicots. Overall findings strengthen the hypothesis that apomixis as a whole may have evolved multiple times in angiosperm evolution following different developmental pathways deviating to different extents from sexuality. Recent developments on the genetic control of apomixis in model species are also presented and adequately discussed in order to shed additional light on the antagonist theories of gain- and loss-of-function over sexuality.
Topics: Apomixis; Evolution, Molecular; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; Magnoliopsida; Plant Proteins; Seeds
PubMed: 32731368
DOI: 10.3390/genes11080859