Gamete Development Research Articles

GhGME31D identified to regulate AsA activation in response to alkali stress from GME gene family implications in cotton

Vitamin C, also referred to as ascorbic acid (AsA), is recognized for its capacity to cure and avert scurvy, and it is crucial for regular human growth and development. In various crops, AsA participates in stress response mechanisms mediated by abscisic acid and has been discovered to have a crucial function in the morphogenesis, growth, development, and production of male gametes in plants. GDP-D-mannose 3′,5′-epimerase (GME) is essential in the synthesis of vitamin C. Our research identified 91, 83, 51, and 46 genes, respectively, found in G. barbadense (GbGMEs), G. hirsutum (GhGMEs), G. arboretum (GaGMEs), and G. raimondii (GrGMEs). Plants resulting from VIGS infection with GhGME31D clearly showed yellowing, water loss and wilting of leaves and black spots on stems. Measurement of MDA and AsA levels indicated that the plants were more damaged. This indicates that AsA has a substantial impact on plant growth and development.

A systematic review of the toxic potential of parabens in fish.

Parabens are the most prevalent ingredients in cosmetics and personal care products (PCPs). They are colorless and tasteless and exhibit good stability when combined with other components. Because of these unique physicochemical properties, they are extensively used as antimicrobial and antifungal agents. Their release into the aquatic ecosystem poses potential threats to aquatic organisms, including fish. We conducted an electronic search in PubMed (http://www.ncbi.nlm.nih.gov/pubmed) using the search term parabens and fish and sorted 93 articles consisting of methyl paraben (MTP), ethyl paraben (ETP), propyl paraben (PPP), butyl paraben (BTP), and benzyl paraben (BNP) in several fish species. Furthermore, we confined our search to six fish species (common carp, Cyprinus carpio; fathead minnows, Pimephales promelas; Japanese medaka, Oryzias latipes; rainbow trout, Oncorhynchus mykiss; Nile tilapia, Oreochromis niloticus; and zebrafish, Danio rerio) and four common parabens (MTP, ETP, PPP, and BTP) and sorted 48 articles for review. Our search indicates that among all six fish, zebrafish was the most studied fish and the MTP was the most tested paraben in fish. Moreover, depending on the alkyl chain length and linearity, long-chained parabens were more toxic than the parabens with short chains. Parabens can be considered endocrine disruptors (EDs), targeting estrogen-androgen-thyroid-steroidogenesis (EATS) pathways, blocking the development and growth of gametes, and causing intergenerational toxicity to impact the viability of offspring/larvae. Paraben exposure can also induce behavioral changes and nervous system disorders in fish. Although the USEPA and EU limit the use of parabens in cosmetics and pharmaceuticals, their prolonged persistence in the environment may pose an additional health risk to humans.

Heat Stress Inhibits Pollen Development by Degrading mRNA Capping Enzyme ARCP1 and ARCP2.

Pollen development and germination are critical for successful generation of offspring in plants, yet they are highly susceptible to heat stress (HS). However, the molecular mechanism underlying this process has not been fully elucidated. In this study, we highlight the essential roles of two mRNA capping enzymes, named Arabidopsis mRNA capping phosphatase (ARCP) 1 and 2, in regulating male and female gamete development. The transmission efficiencies of gametes carrying arcp1 arcp2 from arcp1+/- arcp2-/- and arcp1-/- arcp2+/- mutants are 30% and zero, respectively. These mutants exhibited a significant increase in misshaped pollen, with germination rates approximately half of those in wild type. ARCP1/2 exhibit RNA triphosphatase and RNA guanylyltransferase activities, which are required for proper pollen development. Through RNA-seq analysis, genes involved in pollen development/germination and HS response were identified as downregulated genes in pollen from arcp1+/- arcp2-/- mutant. Furthermore, ARCP2 protein is degraded under HS condition, and inducing the expression of ARCP2 can increase the pollen germination rate under elevated temperature. We propose that HS triggers the degradation of mRNA capping enzymes, which in turn disrupts the transcriptome that required for pollen development and pollen germination and ultimately leads to male sterility.

Transcriptome analysis of the effects of high temperature on zygotic genome activation in porcine embryos

Damage to the development of porcine gametes and embryos caused by high temperatures (HT) is one of the main reasons for the decline in the economic benefits of the livestock industry. Zygotic genome activation (ZGA) marks the beginning of gene expression programs in mammalian pre-implantation embryos. In pigs, ZGA occurs at the 4-cell (4 C) stage, indicating that correct gene expression at this stage plays an important regulatory role in embryonic development. However, the effect of the HT environment on early porcine embryonic development and the RNA expression profile of ZGA remain unclear. In this study, we compared the RNA transcription patterns of porcine 4 C embryos under normal and HT conditions using RNA-seq and identified 326 differentially expressed genes (DEGs). These changes were mainly related to DNA polymerase activity, DNA replication, and nucleotidyltransferase activity. In addition, entries for reverse transcription and endonuclease activity were enriched, indicating that ZGA interfered under HT conditions. Further comparison of the experimental results with the porcine ZGA gene revealed 39 ZGA genes among the DEGs. KEGG and GSEA analysis showed that the oxidative phosphorylation pathway was significantly enriched and signaling pathways related to energy metabolism were significantly downregulated. We also found that NDUFA6 and CDKN1A were located at the center of the protein-protein interaction network diagram of the DEGs. In summary, HT conditions affect mitochondrial function and oxidative phosphorylation levels, and lead to changes in the expression pattern of ZGA in early porcine embryos, with its hub genes NDUFA6 and CDKN1A.

Heatwaves exacerbate pollen limitation through reductions in pollen production and pollen vigour.

Increasingly frequent heat waves threaten the reproduction of flowering plants; compromising the future persistence, adaptive capacity, and dispersal of wild plant populations, and also the yield of fruit-bearing crop plants. Heat damages the development of sensitive floral organs and gametes, which inhibits pollen germination, pollen tube growth, and fertilization. However, the role of heat has not been integrated into the framework of pollen quantity and quality limitation and how heat influences the success of cross and self-pollination. We exposed developing flowers to either controlled temperature (25 °C:20 °C) or extreme heat (35 °C:20 °C) over 72h. We then hand-pollinated them with either crossed or self-derived pollen from the same temperature treatment to determine the direct and interactive effects of simulated heatwaves on pollen tube growth and resulting seed set. We also collected anthers from virgin flowers to measure heat impacts on pollen production. Under cooler control temperatures pollen tube survival of self-derived pollen was approximately 27% lower than that of crossed pollen. Pollen tube survival in heat-treated cross-pollinated and heat-treated self-pollinated flowers were 71% and 77% lower compared to flowers cross-pollinated at control temperatures. These differences in pollen tube survival rate between heat-treated cross-pollinated and heat-treated self-pollinated flowers were insignificant. Furthermore, extreme heat reduced seed set by 87%, regardless of pollen origin, and also reduced pollen production during flower development by approximately 20%. Our results suggest flowers that develop during heatwaves are likely to experience exacerbated pollen quantity and quality limitation driven by changes in pollen production and pollen vigour. Heatwave-induced pollen limitation will likely reduce crop yields in agricultural systems, and depress mating and reproduction in wild plant species, the latter of which may hinder the adaptive capacity of plants to a rapidly changing world.

Comparative transcriptomics analysis reveals stage-specific gene expression profiles associated with gamete formation in Allium sativum L.

Commercial cultivars of garlic, a popular condiment, are sterile, making genetic variation and germplasm innovation of this plant challenging. Understanding mechanism of gamete sterility in garlic and their key regulatory networks is therefore important for fertility restoration. In this work, we conducted a detailed phenotypic analysis of fertile and sterile garlic genotypes and found that enlargement of topset in the inflorescence of sterile genotypes led to abnormal flowers. Additional cytological observations showed that aberrant meiotic cytokinesis in sterile garlic ultimately resulted in pollen degeneration. Transcriptomics analysis of sterile and fertile genotypes identified possible molecular mechanisms underlying gamete abortion. A total of 100 710 differentially expressed genes (DEGs) between the fertile and sterile garlic flowers at three stages of gamete development were identified, many of which were involved in homologous chromosome synapsis during meiosis, MYB transcription factor regulation, ribosome biogenesis and plant hormone signal transduction. Taken together, these results provide insight into the molecular mechanisms and regulatory networks underlying gamete development in garlic and point to a set of candidate genes for further functional characterization.

Property and Activity Refinement of Dihydroquinazolinone-3-carboxamides as Orally Efficacious Antimalarials that Target PfATP4.

To contribute to the global effort to develop new antimalarial therapies, we previously disclosed initial findings on the optimization of the dihydroquinazolinone-3-carboxamide class that targets PfATP4. Here we report on refining the aqueous solubility and metabolic stability to improve the pharmacokinetic profile and consequently in vivo efficacy. We show that the incorporation of heterocycle systems in the 8-position of the scaffold was found to provide the greatest attainable balance between parasite activity, aqueous solubility, and metabolic stability. Optimized analogs, including the frontrunner compound S-WJM992, were shown to inhibit PfATP4-associated Na+-ATPase activity, gave rise to a metabolic signature consistent with PfATP4 inhibition, and displayed altered activities against parasites with mutations in PfATP4. Finally, S-WJM992 showed appreciable efficacy in a malaria mouse model and blocked gamete development preventing transmission to mosquitoes. Importantly, further optimization of the dihydroquinazolinone class is required to deliver a candidate with improved pharmacokinetic and risk of resistance profiles.

Cannabidiol exposure during embryonic period caused serious malformation in embryos and inhibited the development of reproductive system in adult zebrafish

Cannabidiol (CBD) is a non-psychoactive component of cannabis with potential applications in biomedicine, food, and cosmetics due to its analgesic, anti-inflammatory, and anticonvulsant properties. However, increasing reports of adverse CBD exposure events underscore the necessity of evaluating its toxicity. In this study, we investigated the developmental toxicity of CBD in zebrafish during the embryonic (0–4 dpf, days post fertilization) and early larval stages (5–7 dpf). The median lethal concentration of CBD in embryos/larvae is 793.28 μg/L. CBD exhibited concentration-dependent manner (ranging from 250 to 1500 μg/L) in inducing serious malformed somatotypes, like shorter body length, pericardial cysts, vitelline cysts, spinal curvature, and smaller eyes. However, no singular deformity predominates. The 5-month-old zebrafish treated with 100 and 200 μg/L of CBD during the embryonic and early larval stages produced fewer offspring with higher natural mortality and malformation rate. Gonadal growth and gamete development were inhibited. Transcriptomic and metabolomic analyses conducted with 400 μg/L CBD on embryos/larvae from 0 to 5 dpf suggested that CBD promoted the formation and transportation of extracellular matrix components on 1 dpf, promoting abnormal cell division and migration, probably resulting in random malformed somatotypes. It inhibited optical vesicle development and photoreceptors formation on 2 and 3 dpf, resulting in damaged sight and smaller eye size. CBD also induced an integrated stress response on 4 and 5 dpf, disrupting redox, protein, and cholesterol homeostasis, contributing to cellular damage, physiological dysfunction, embryonic death, and inhibited reproductive system and ability in adult zebrafish. At the tested concentrations, CBD exhibited developmental toxicity, lethal toxicity, and reproductive inhibition in zebrafish. These findings demonstrate that CBD threatens the model aquatic animal, highlighting the need for additional toxicological evaluations of CBD before its inclusion in dietary supplements, edible food, and other products.

Powerful QTL mapping and favorable allele mining in an all-in-one population: a case study of heading date.

The multiparent advanced generation intercross (MAGIC) population is characterized with great potentials in power and resolution of quantitative trait locus (QTL) mapping, but single nucleotide polymorphism (SNP)-based GWAS does not fully reach its potential. In this study, a MAGIC population of 1021 lines was developed from four Xian and four Geng varieties from five subgroups of rice. A total of 44000 genes showed functional polymorphisms among eight parents, including frameshift variations or premature stop codon variations, which provides the potential to map almost all genes of the MAGIC population. Principal component analysis results showed that the MAGIC population had a weak population structure. A high-density bin map of 24414 bins was constructed. Segregation distortion occurred in the regions possessing the genes underlying genetic incompatibility and gamete development. SNP-based association analysis and bin-based linkage analysis identified 25 significant loci and 47 QTLs for heading date, including 14 known heading date genes. The mapping resolution of genes is dependent on genetic effects with offset distances of <55kb for major effect genes and <123kb for moderate effect genes. Four causal variants and noncoding structure variants were identified to be associated with heading date. Three to four types of alleles with strong, intermediate, weak, and no genetic effects were identified from eight parents, providing flexibility for the improvement of rice heading date. In most cases, japonica rice carries weak alleles, and indica rice carries strong alleles and nonfunctional alleles. These results confirm that the MAGIC population provides the exceptional opportunity to detect QTLs, and its use is encouraged for mapping genes and mining favorable alleles for breeding.

Hypoxia, NSAIDs, and autism: A biocultural analysis of stressors in gametogenesis.

Cultural and generational trends have increasingly favored "anti-inflammatory" action, innovating a new class of analgesic, non-steroidal anti-inflammatory drugs (NSAIDs) in the 20th century. The modern human body has been molded over evolutionary time and while acknowledging inflammation can be pathologically entwined, it also serves an important role in healthy folliculogenesis and ovulation, shaping cues that drive needed vascular change. This review argues that because of anti-inflammatory action, the cultural invention of NSAIDs represents a particular stressor on female reproductive-age bodies, interacting with natural, underlying variation and placing limits on healthy growth and development in the follicles, creating potential autism risk through hypoxia and mutagenic or epigenetic effects. Since testes are analogs to ovaries, the biological grounding extends naturally to spermatogenesis. This review suggests the introduction of over-the-counter NSAIDs in the 1980s failed to recognize the unique functioning of reproductive-age bodies, challenging the cyclical inflammation needed for healthy gamete development. NSAIDs are framed as one (notable) stressor in an anti-inflammatory era focused on taming the risks of inflammation in modern human life.

Reproductive Toxicity Caused by Zearalenone on Animals and Its Possible Interventions

Zearalenone (ZEN) is a mycotoxin that is usually found in moldy grains. ZEN causes reproductive toxicity to domestic animals by interfering with follicular and embryonic development, reducing sperm vitalityand destroying the homeostasis of endogenous hormones, leading to reproductive system diseases such as abortion, ovarian dysfunctionand stillbirth. The reproductive damage caused by zearalenone is mainly attributed to the factors as follows: (1) interaction with estrogen receptor; (2) induction of oxidative stress; (3) induction of apoptosis, necrosis, autophagyand iron prolapse and (4) interference with cell replication cycle. Natural compounds and micro-nutrients have the potential to alleviate the oxidative stress caused by ZEN. In addition, some microorganisms and enzymes have also shown good detoxification effects. Therefore, in this review, we focus on the damage caused by ZEN on animal gamete development and embryonic development, its molecular mechanismsand suggested some potential mitigation measures for the prevention of ZEN-induced toxicity to provide information for preventing toxicity associated with ZEN as well as serve as a foundation for further development of drug candidates for the treatment of ZEN induced damage.

Norepinephrine Neurons in the Nucleus of the Solitary Tract Suppress Luteinizing Hormone Secretion in Female Mice.

Stress impairs fertility, at least in part, via inhibition of gonadotropin secretion. Luteinizing hormone (LH) is an important gonadotropin that is released in a pulsatile pattern in males and in females throughout the majority of the ovarian cycle. Several models of stress, including acute metabolic stress, suppress LH pulses via inhibition of neurons in the arcuate nucleus of the hypothalamus that coexpress kisspeptin, neurokinin B, and dynorphin (termed KNDy cells) which form the pulse generator. The mechanism for inhibition of KNDy neurons during stress, however, remains a significant outstanding question. Here, we investigated a population of catecholamine neurons in the nucleus of the solitary tract (NTS), marked by expression of the enzyme dopamine beta-hydroxylase (DBH), in female mice. First, we found that a subpopulation of DBH neurons in the NTS is activated (express c-Fos) during metabolic stress. Then, using chemogenetics, we determined that activation of these cells is sufficient to suppress LH pulses, augment corticosterone secretion, and induce sickness-like behavior. In subsequent studies, we identified evidence for suppression of KNDy cells (rather than downstream signaling pathways) and determined that the suppression of LH pulses was not dependent on the acute rise in glucocorticoids. Together these data support the hypothesis that DBH cells in the NTS are important for regulation of neuroendocrine and behavioral responses to stress.

The Role of N6-methyladenosine Modification in Gametogenesis and Embryogenesis: Impact on Fertility.

The most common epigenetic modification of messenger RNAs (mRNAs) is N6-methyladenosine (m6A), which is mainly located near the 3' untranslated region of mRNAs, near the stop codons, and within internal exons. The biological effect of m6A is dynamically modulated by methyltransferases (writers), demethylases (erasers), and m6A-binding proteins (readers). By controlling post-transcriptional gene expression, m6A has a significant impact on numerous biological functions, including RNA transcription, translation, splicing, transport, and degradation. Hence, m6A influences various physiological and pathological processes, such as spermatogenesis, oogenesis, embryogenesis, placental function, and human reproductive system diseases. During gametogenesis and embryogenesis, genetic material undergoes significant changes, including epigenomic modifications such as m6A. From spermatogenesis and oogenesis to the formation of an oosperm and early embryogenesis, m6A changes occur at every step. m6A abnormalities can lead to gamete abnormalities, developmental delays, impaired fertilization, and maternal-to-zygotic transition blockage. Both mice and humans with abnormal m6A modifications exhibit impaired fertility. In this review, we discuss the dynamic biological effects of m6A and its regulators on gamete and embryonic development and review the possible mechanisms of infertility caused by m6A changes. We also discuss the drugs currently used to manipulate m6A and provide prospects for the prevention and treatment of infertility at the epigenetic level.

Southeast Florida large Orbicella faveolata are highly fecund without evident disease intervention effects

The recent widespread mortality and tissue loss in Florida from stony coral tissue loss disease (SCTLD) has propelled the need for assisted reproduction to restore reefs, especially for the ESA listed species Orbicella faveolata. In situ gamete collection can be challenging due to the weather and resources (boats and divers) required during the expected spawning window. In the northern portion of the Florida coral reef tract, coral spawn collection has been even more difficult due to historical inconsistency in annual spawning times and the potential for “zombie” corals, i.e. large but reproductively senescent individuals. Therefore, we examined the current reproductive potential of seven large (&amp;gt;2 m diameter) O. faveolata colonies from this region, quantified their fecundity, and estimated the spawning timeframe using histology. Additionally, we explored whether previous SCTLD lesion amoxycillin treatments affected reproductive metrics. Understanding the reproductive capacity and spawning timing of these large corals, given their history of disease and disease treatment, is critical to evaluate potential impacts of SCTLD treatments and the success of assisted reproduction efforts. The histological analysis coupled with in-water observations indicated a probable split-spawn in these individuals in 2020, although the dates of spawning may not be consistent with predictions for the wider Caribbean or with other colonies in Miami and the Florida Keys. All seven large O. faveolata colonies were found to contain abundant oocytes, with no obvious impact of SCTLD treatments on gamete development or fecundity.

Application of ultrasonography in abalone gonadal evaluation

The precise assessment of the gonad status and gamete development level is an essential step in abalone breeding. However, traditional methods are damaging to the animals, causing the waste of a quality parent. Ultrasound imaging as a noninvasive technique is a candidate substitute. This study aimed to verify the application of ultrasonography to the assessment of abalone gonad condition. Pacific abalones (n = 20) were randomly selected for ultrasonography, another six abalones in different gonad maturation stages (mature, between mature and immature, and immature) were also subjected to the same detection and histological analysis. Abalones (n = 10) were induced to spawn, and the changes in the gonad index and the types of germ cells were determined before and after spawning. Thirty-six female abalones were selected and divided into a high-gonad index group (HGI) and a low-gonad index group (LGI) according to the gonad index determined by ultrasonography, and their reproductive performance was compared during the entire breeding process. There was no significant difference in gonad index or gonad relative average thickness (GRAT) obtained from ultrasonography and histological methods. The gonad index and GRAT measured by ultrasound images significantly decreased after spawning. After spawning, a minimal quantity of mature gametes remained in gonad tissue as reflected in histology images. In a reproductive trial, the HGI group showed comprehensive and overwhelming reproductive advantages compared to the LGI group in total fecundity, relative fecundity, fertilization rate, hatching rate, abnormality rate, and attachment rate. Ultrasonography was demonstrated to be useful as a noninvasive method to evaluate abalone gonad condition. The ultimate goal is to achieve tracing and monitoring the abalone reproductive cycle through the ultrasound technique.

Перебіг гаметогенезу у вузькопалих річкових раків (Astacus leptodactylus Eschscholtz, 1823) в умовах водойм Придніпров’я

Purpose. Detailed study of the stages of reproductive development (oogenesis and spermatogenesis) of crayfish using the example of the narrow-clawed crayfish Astacus leptodactylus Eschscholtz, 1823 in reservoirs of the Dnieper region. Methodology. The study was conducted during the period of 2022-2023. The material for the study were individuals of the narrow-clayed crayfish A. leptodactilus. A morphometric analysis was performed, after which the crayfish were preserved in an alcohol solution (70% ethanol and 2% glycerol) for the slide of histological cross-sections. Histological slides of crayfish gonads were made in accordance with generally accepted histological methods. The analysis of the cross-sections was carried out using a microscope and a digital camera. Descriptions of the slides were made using atlases of histology of decapods. Findings. It has been found that the gonads exhibited an asynchronous development and were in stages C, D, E, F, with a significant number of oocytes in stage C. The diameter of oocytes in phase D mainly ranged from 195.72 ± 12.43 μm with an area of 38,21 μm². The nucleus had a diameter of 48.14 ± 1.44 μm. In phases E, the size of oocytes reached a diameter of 259.24 ± 76.18 μm and an area of 52,850 ± 5,760 μm². Throughout phase D, the diameter of vacuoles was 18.45 ± 0.86 μm. In phase E, the diameter of vacuoles increased to 26.55 ± 1.24 μm, and as soon as in the transitional phase E–F, vacuoles merged massively with individual non-merging vacuoles having a diameter of 25.22 ± 1.12 μm. At the terminal stage F, oocytes reached definitive sizes and were ready for ovulation. The average size of larvae was 2600 ± 0.093 μm in diameter. The course of spermatogenesis in crayfish males was characterized by synchronous development of gametes. The analysis of sections showed that the area of spermatocytes was 43.14 ± 0.74 μm with a diameter of 7.14 ± 0.23 μm². In turn, the nuclei of spermatocytes had dimensions of 21.64 ± 0.35 μm² and 5.24 ± 0.02 μm in diameter. Originality. A comprehensive analysis of crayfish gametogenesis was conducted for the first time in the zones of the reproductive range of the Dnieper reservoirs. Some features of the stages of oogenesis and spermatogenesis were identified and the impact of the ecological regime on the reproduction of crayfish was studied. Keywords: narrow-clawed crayfish, water bodies, reproduction, ecological state of water bodies, reservoir, eggs, gametogenesis.

Potential Implications of Acid-Sensing Ion Channels ASIC2 and ASIC4 in Gonadal Differentiation of Dicentrarchus labrax Subjected to Water Temperature Increase during Gonadal Development.

In this study, the expression and implication of acid-sensing ion channels 2 and 4 (ASIC2 and ASIC4) in the gonadal sex differentiation of Dicentrarchus labrax (D. labrax), subjected to increasing water temperatures during gonadal development, were evaluated. Two groups were selected: a control group (CG), in which the average water temperature was maintained at 15 °C and increased to 20 °C in 20 days until weaning; and an experimental group (EG), in which the water temperature was retained at 15 °C for 60 days; thereafter, the temperature was increased daily by 0.5 °C until it reached 20 °C up to the weaning time. Ten fish from the CG and 13 fish from the EG were sampled randomly on the 335th day after hatching (dph). A higher percentage of gonad differentiation in ovaries rather than in testes was observed in the EG compared to the CG (p = 0.01). ASIC2 and ASIC4 were detected for the first time in D. labrax ovaries by indirect immunofluorescence. Both ASIC2 and ASIC4 were expressed in previtellogenic oocytes of ovaries and in scattered cells within some testes, and were most likely intratesticular previtellogenic oocytes in both the CG and EG groups. The CG group showed a higher expression of ASIC4 than the EG cohort (p < 0.05). The results gathered in this study revealed the capacity of water temperature to influence both gonadal differentiation and growth in this gonochoristic fish species, and suggests the possible role of ASIC2 and ASIC4 in gonad differentiation and gamete development in D. labrax.

Generation of marmoset primordial germ cell-like cells under chemically defined conditions.

Primordial germ cells (PGCs) are the embryonic precursors of sperm and oocytes, which transmit genetic/epigenetic information across generations. Mouse PGC and subsequent gamete development can be fully reconstituted in vitro, opening up new avenues for germ cell studies in biomedical research. However, PGCs show molecular differences between rodents and humans. Therefore, to establish an in vitro system that is closely related to humans, we studied PGC development in vivo and in vitro in the common marmoset monkey Callithrix jacchus (cj). Gonadal cjPGCs at embryonic day 74 express SOX17, AP2Ɣ, BLIMP1, NANOG, and OCT4A, which is reminiscent of human PGCs. We established transgene-free induced pluripotent stem cell (cjiPSC) lines from foetal and postnatal fibroblasts. These cjiPSCs, cultured in defined and feeder-free conditions, can be differentiated into precursors of mesendoderm and subsequently into cjPGC-like cells (cjPGCLCs) with a transcriptome similar to human PGCs/PGCLCs. Our results not only pave the way for studying PGC development in a non-human primate in vitro under experimentally controlled conditions, but also provide the opportunity to derive functional marmoset gametes in future studies.

Genetic factors of reproductive disorders in female

Successful reproduction in mammals requires gamete development, fertilization, and early embryonic development. Defects in any of these processes can lead to infertility, recurrent miscarriages, and congenital defects. The clinical recognition of the genetic causes of female reproductive insufficiency using increasingly advanced genetic technologies poses a serious challenge for reproductive medicine in the 21 st century. Herein, current literature on genetic factors involved in reproductive losses was summarized. A literature search was conducted using Web of Science, MEDLINE, and PubMed databases for articles written in English on the genetic causes of women’s reproductive health disorders. Future implementation of whole-exome and -genome sequencing is expected to identify numerous genetic factors responsible for oocyte quality. Which will aid in increasing the likelihood of successful female reproductive function, improve the outcomes of assisted reproductive technologies, optimize treatment, and facilitate genetic diagnosis of patients.

Nano-graphene oxide particles induce inheritable anomalies through altered gene expressions involved in oocyte maturation

The inheritable impact of exposure to graphene oxide nanoparticles (GO NPs) on vertebrate germline during critical windows of gamete development remain undetermined to date. Here, we analyzed the transgenerational effects of exposure to nano-graphene oxide particles (nGO) synthesized in house with lateral dimensions 300–600 nm and surface charge of −36.8 mV on different developmental stages of germ cells (GCs): (1) during GCs undergoing early development and differentiation, and (2) during GCs undergoing gametogenesis and maturation in adulthood. Biocompatibility analyses in Japanese medaka embryos showed lethality above 1 µg/ml and also an aberrant increase in germ cell count of both males and females at doses below the lethal dose. However, no lethality or anomalies were evident in adults up to 45 µg/ml. Long term exposure of embryos and adults for 21 days resulted in reduced fecundity. This effect was transmitted to subsequent generations, F1 and F2. Importantly, the inheritable effects of nGO in adults were pronounced at a high dose of 10 µg/ml, while 1 µg/ml showed no impact on the germline indicating lower doses used in this study to be safe. Further, expressions of selected genes that adversely affected oocyte maturation were enhanced in F1 and F2 individuals. Interestingly, the inheritance patterns differed corresponding to the stage at which the fish received the exposure.