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In vitro gametogenesis (IVG), the reconstitution of germ cell development in vitro, is an emerging stem cell-based technology with profound implications for reproductive science. Despite researchers' long-term goals for future clinical applications, little is currently known about the views of IVG held by the stakeholders potentially most affected by its introduction in humans. We conducted focus groups and interviews with 80 individuals with lived experience of infertility and/or LGBTQ+ family formation in the US, two intersecting groups of potential IVG users. Respondents expressed hope that IVG would lead to higher reproductive success than current assisted reproductive technology (ART), alleviate suffering associated with ART use, and promote greater social inclusion, while expressing concerns predominantly framed in terms of equity and safety. These findings underscore the importance of sustained engagement with stakeholders with relevant experience to anticipate the implications of IVG for research and clinical translation.

Microtubules (MTs) are dynamic components of the cytoskeleton and play essential roles in morphogenesis and maintenance of tissue and cell integrity. Despite recent advances in understanding MT ultrastructure, organization, and growth control, how cells regulate MT organization at the cell cortex remains poorly understood. The EFA-6/EFA6 proteins are recently identified membrane-associated proteins that inhibit cortical MT dynamics. Here, combining visualization of endogenously tagged C. elegans EFA-6 with genetic screening, we uncovered tubulin-dependent regulation of EFA-6 patterning. In the mature epidermal epithelium, EFA-6 forms punctate foci in specific regions of the apical cortex, dependent on its intrinsically disordered region (IDR). We further show the EFA-6 IDR is sufficient to form biomolecular condensates in vitro. In screens for mutants with altered GFP::EFA-6 localization, we identified a novel gain-of-function (gf) mutation in an α-tubulin tba-1 that induces ectopic EFA-6 foci in multiple cell types. tba-1(gf) animals exhibit temperature-sensitive embryonic lethality, which is partially suppressed by efa-6(lf), indicating the interaction between tubulins and EFA-6 is important for normal development. TBA-1(gf) shows reduced incorporation into filamentous MTs but has otherwise mild effects on cellular MT organization. The ability of TBA-1(gf) to trigger ectopic EFA-6 foci formation requires β-tubulin TBB-2 and the chaperon EVL-20/Arl2. The tba-1(gf)-induced EFA-6 foci display slower turnover, contain the MT-associated protein TAC-1/TACC, and require the EFA-6 MTED. Our results reveal a novel crosstalk between cellular tubulins and cortical MT regulators in vivo.

The fishing cat, Prionailurus viverrinus, faces a population decline, increasing the importance of maintaining healthy zoo populations. Unfortunately, zoo-managed individuals currently face a high prevalence of transitional cell carcinoma (TCC), a form of bladder cancer. To investigate the genetics of inherited diseases among captive fishing cats, we present a chromosome-scale assembly, generate the pedigree of the zoo-managed population, reaffirm the close genetic relationship with the Asian leopard cat (Prionailurus bengalensis), and identify 7.4 million single nucleotide variants (SNVs) and 23,432 structural variants (SVs) from whole genome sequencing (WGS) data of healthy and TCC cats. Only BRCA2 was found to have a high recurrent number of missense mutations in fishing cats diagnosed with TCC when compared to inherited human cancer risk variants. These new fishing cat genomic resources will aid conservation efforts to improve their genetic fitness and enhance the comparative study of feline genomes.

Retinitis pigmentosa (RP) is a common form of retinal dystrophy that can be caused by mutations in any one of dozens of rod photoreceptor genes. The genetic heterogeneity of RP represents a significant challenge for the development of effective therapies. Here, we present evidence for a potential gene-independent therapeutic strategy based on targeting Nr2e3, a transcription factor required for the normal differentiation of rod photoreceptors. Nr2e3 knockout results in hybrid rod photoreceptors that express the full complement of rod genes, but also a subset of cone genes. We show that germline deletion of Nr2e3 potently protects rods in three mechanistically diverse mouse models of retinal degeneration caused by bright-light exposure (light damage), structural deficiency (rhodopsin-deficient Rho-/- mice), or abnormal phototransduction (phosphodiesterase-deficient rd10 mice). Nr2e3 knockout confers strong neuroprotective effects on rods without adverse effects on their gene expression, structure, or function. Furthermore, in all three degeneration models, prolongation of rod survival by Nr2e3 knockout leads to lasting preservation of cone morphology and function. These findings raise the possibility that upregulation of one or more cone genes in Nr2e3-deficient rods may be responsible for the neuroprotective effects we observe.

Purpose: Since the genotoxicity of ionizing radiation was demonstrated in the 1920s, its hereditary effects have remained a serious concern for human society. The International Commission on Radiological Protection has highlighted the need for appropriate protection against hereditary effects of radiation in humans. In this paper, we review the literature on the possible multigenerational and transgenerational effects following testicular exposure to radiation, focusing on sperm epigenetic alterations as possible mechanisms. Results: This mini-review highlights that hereditary effects following testicular exposure occur via epigenetic changes of germ cells in animal models, providing implications on human radiation protection. Conclusions: A great amount of epigenomic research data has emerged rapidly since the beginning of this century; thus, a revision of the radiological protection protocols against the hereditary effects of radiation would be no longer inevitable. The collection and analysis of evidence on these effects must be enhanced and further accelerated to formulate appropriate protection protocols in the future. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the probiotic bacteria present in drone milk (DM) and drone larvae (DL). Furthermore, the study aimed to investigate the antibacterial capacity against Staphylococcus and Streptococcus species isolated from animal semen. The in vitro effects of DM and DL on male reproductive cells and rabbit tissues were examined. In addition, the nutritional and chemical composition of both bee products was investigated. Fresh and freeze-dried samples were used to isolate probiotic bacteria identified by MALDI-TOF MS Biotyper. Lactobacilli, especially Apilactobacillus kunkeii, Lactiplantibacillus pentosus, Lactiplantibacillus plantarum, and Secundilactobacillus malefermentas , received the highest identification scores. The best results were observed when targeting S. aureus, S. epidermidis , and S. vitulinus. The freeze-dried materials were tested on rabbit spermatozoa and testicular fragments to ascertain the effects of DM and DL. The results showed that the samples significantly reduced the amount of reactive oxygen species in the reproductive structures which resulted in a decrease in lipid peroxidation. Furthermore, testicular fragments treated in vitro with DM and DL produced considerably more testosterone and cholesterol; crude protein, nitrogenous compounds and fat were all present in higher amounts in DL while the content of reducing sugars was higher in DM. [Display omitted] • The main chemical components of drone milk affect biological activity. • Drone milk showed antimicrobial activity against Staphylococcus and Streptococcus genus. • Drone milk has probiotic effects. • Drone milk affects rabbit spermatozoa. • Effects in vitro of drone milk on rabbit testicular fragments. [ABSTRACT FROM AUTHOR]

The unprecedented loss of global biodiversity is linked to multiple anthropogenic stressors. New conservation technologies are urgently needed to mitigate this loss. The rights, knowledge and perspectives of Indigenous peoples in biodiversity conservation—including the development and application of new technologies—are increasingly recognised. Advances in germplasm cryopreservation and germ cell transplantation (termed 'broodstock surrogacy') techniques offer exciting tools to preserve biodiversity, but their application has been underappreciated. Here, we use teleost fishes as an exemplar group to outline (1) the power of these techniques to preserve genome‐wide genetic diversity, (2) the need to apply a conservation genomic lens when selecting individuals for germplasm cryobanking and broodstock surrogacy and (3) the value of considering the cultural significance of these genomic resources. We conclude by discussing the opportunities and challenges of these techniques for conserving biodiversity in threatened teleost fish and beyond. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of oral pentoxifylline on testicular biometry, histology, and gene expression in stallions subjected to scrotal heat stress. Fourteen stallions were divided into three groups: Control (CRL, n = 4), Testicular Degeneration (DEG, n = 5), and Testicular Degeneration Treated with Pentoxifylline (DEG + PTX, n = 5). Testicular degeneration was induced by scrotal insulation, twice daily, over two consecutive days (D-1 and D0). Starting the next day (D1), oral pentoxifylline (17 mg/kg) was administered every 12 h for 30 days. Testicular biometry was measured using a caliper from D-5 to D60. On days 30 and 60, testicular biopsies were collected for histopathology and gene expression analysis of BAX , CASP8 , CASP9 , FAS , HSF1 , and PTGS2 using RT-qPCR. Pentoxifylline reduced histological damage, with the DEG + PTX group showing less pronounced basal lamina undulation and seminiferous tubule atrophy compared to the DEG group. However, it did not fully prevent lesions like germ cell vacuolization, which was reflected macroscopically by a reduction in testicular volume in both degenerated groups. The protective effects of pentoxifylline on testicular tissue can be attributed to its ability to reduce BAX expression, prevent CASP8 and CASP9 activation, and promote cellular protective mechanisms through HSF1 activation at D30. These results highlight pentoxifylline's potential as a therapeutic agent for equine testicular damage due to scrotal heat stress, suggesting the need for further research on optimal dosage and treatment duration. • Scrotal insulation using a forced hot air system at 45 °C effectively induces testicular degeneration. • Scrotal heat stress activates germ cell apoptosis and leads to severe testicular degeneration. • Oral treatment with pentoxifylline reduces parenchymal damage, including mitigating seminiferous tubule atrophy. • Pentoxifylline decreases germ cell apoptosis by downregulating BAX and preventing the activation of CASP8 and CASP9. [ABSTRACT FROM AUTHOR]

The H3K79 methyltransferase DOT1L is essential for multiple aspects of mammalian development where it has been shown to regulate gene expression. Here, by producing and integrating epigenomic and spike-in RNA-seq data, we decipher the molecular role of DOT1L during mouse spermatogenesis and show that it has opposite effects on gene expression depending on chromatin environment. On one hand, DOT1L represses autosomal genes that are devoid of H3K79me2 at their bodies and located in H3K27me3-rich/H3K27ac-poor environments. On the other hand, it activates the expression of genes enriched in H3K79me2 and located in H3K27me3-poor/H3K27ac-rich environments, predominantly X chromosome-linked genes, after meiosis I. This coincides with a significant increase in DOT1L expression at this stage and a genome-wide acquisition of H3K79me2, particularly on the sex chromosomes. Taken together, our results show that H3K79me2 positively correlates with male germ cell genetic program throughout spermatogenesis, with DOT1L predominantly inhibiting rather than activating gene expression. Interestingly, while DOT1L appears to directly regulate the (re)activation of X genes following meiotic sex chromosome inactivation, it also controls the timely expression of (autosomal) differentiation genes during spermatogenesis. Epigenomic and transcriptomic analyses reveal that, during mouse spermatogenesis, the H3K79 methyltransferase DOT1L has opposite effects on autosomal and X-linked gene expression depending on local chromatin enrichment in H3K79me2 and in H3K27me3. [ABSTRACT FROM AUTHOR]

Sertoli cells (SCs), as the somatic cells in the testis of male mammals, play a crucial role in the close association with germ cells. The blood-testicular barrier (BTB), established by their tight junctions, provides immune protection to germ cells, leading to their characterization as "sentinel" cells. Moreover, the physiological process of testicular development and spermatogenesis in male animals is intricately tied to the secretory activities of SCs. These cells secrete a diverse array of proteins and cytokines that interact with various targets, working in concert with mechanisms in the spermatogenesis pathway and contributing to each stage, from spermatogonial cell division to the maturation of spermatozoa. Hence, the secretory products of SCs are pivotal in fostering germ cell development and directing the appropriate maturation of sperm. This study is dedicated to investigating the varied secretions of SCs, outlining their critical functions throughout distinct phases of spermatogenesis, thus elucidating the substantial influence of SC secretion on male fertility. Furthermore, it offers valuable perspectives on reproductive disorders stemming from irregular spermatogenesis in clinical contexts. [ABSTRACT FROM AUTHOR]

Background: Spermatogenesis is a complex process of cellular differentiation that commences with the division of spermatogonia stem cells, ultimately resulting in the production of functional spermatozoa. However, a substantial gap remains in our understanding of the molecular mechanisms and key driver genes that underpin this process, particularly in invertebrates. The dwarf surfclam (Mulinia lateralis) is considered an optimal bivalve model due to its relatively short generation time and ease of breeding in laboratory settings. Results: In this study, over 4,600 testicular cells from various samples were employed to identify single-cell heterogeneity on a more comprehensive scale. The four germ cell populations (spermatogonia, primary spermatocytes, secondary spermatocytes, and round spermatids/spermatozoa) and three somatic populations (follicle cell, hemocyte, and nerve cell) were characterized. The four types of germ cells exhibited disparate cell cycle statuses and an uninterrupted developmental trajectory, progressing from spermatogonia to spermatids/spermatozoa. Pseudotime analysis indicates that gene expression, translation, ATP metabolic process, and microtubule-based process are involved in the transition of germ cell types. Weighted gene coexpression network analysis (WGCNA) identified four modules corresponding to the four types of germ cells, as well as key transcription factors (e.g., MYC, SREBF1, SOXH) that may play a critical role in these cell types. Furthermore, our findings revealed that there is extensive bidirectional communication between the somatic cells and the germline cells, including the FGF and TGF-β signaling pathways, as well as other ligand-receptor pairs, such as NTN1-NEO1 and PLG-PLGRKT. Conclusions: This study provides a comprehensive single-cell transcriptome landscape of the gonad, which will contribute to the understanding of germ cell fate transition during spermatogenesis, and the development of germ cell manipulation technologies in mollusks. [ABSTRACT FROM AUTHOR]

The present study describes the differentiation process of male germ cells in Octopus vulgaris, the morphology of sperm in the testis and spermatophore, and the sperm released after the spermatophoric reaction. During spermatogenesis, the male sperm cell gradually elongates from a round shape, with cytoplasm shifting toward the head and the acrosome forming. Additionally, in the spermatid stage, the flagellum develops within the posterior nuclear channel and extends outside the cytoplasm. The sperm is composed of a head and a tail. The head is approximately 17.9 μm long and consists of a highly electron-dense nucleus and a helical acrosome. The tail is divided into three parts: the mid-piece, principal-piece, and end-piece. The mid-piece forms a mitochondrial sheath with 7–8 mitochondria surrounding a "9+2" axoneme. The principal-piece is composed of an axoneme, outer dense fibers, and fibrous sheath, while the end piece lacks outer dense fibers or fibrous sheath. The sperm in the testis and spermatophore, and the sperm released after the spermatophoric reaction have the same structure. However, in the sperm located in the testis and spermatophore, the structure of the acrosome is unclear due to the presence of cytoplasm in the head. In contrast, sperm released after the spermatophoric reaction lack their cytoplasm, revealing the helical acrosome. This unique sperm morphology, adapted for internal fertilization, is thought to be advantageous for fertilization and long-term storage within the female reproductive system. [ABSTRACT FROM AUTHOR]

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The proteasome, an evolutionarily conserved proteolytic complex comprising the 20S core particle and 19S regulatory particles, performs both shared and distinct functions across various tissues and organs. Spermatogenesis, a highly complex developmental process, relies on proteasome activity at multiple stages to regulate protein turnover. In this study, we selected the 20S subunit PSMA1 and 19S regulatory subunit PSMD2 to investigate the potential functions of the proteasome in spermatogenesis. Using Psma1-EGFP and Psmd2- mCherry knock-in mouse models, we confirmed the expression of both subunits in all spermatogenic cell types, with pronounced presence in early germ cell development. To further clarify their functional significance, we specifically knocked out Psma1 and Psmd2 in germ cells. Deletion of either PSMA1 or PSMD2 led to disrupted spermatogenesis, characterized by the complete absence of sperm in the epididymis. Subsequent analysis indicated that loss of these proteasome components impaired meiotic initiation. Psma1 and Psmd2 knockout germ cells showed accumulation of DMRT1, a key regulator of mitosis-to-meiosis transition, leading to a reduction in STRA8 levels and consequent disruption of meiosis initiation. This study sheds light on the molecular mechanisms that govern meiotic initiation and identifies potential genes associated with male infertility. [ABSTRACT FROM AUTHOR]

Croton sylvaticus, a tropical African plant, is traditionally used to treat several diseases, including fever, inflammation, and malaria. Essential oils (EOs) from the plant's leaves, roots, and trunk bark were obtained by hydrodistillation, and their chemical composition was analyzed by gas chromatography–mass spectrometry (GC-MS). The major constituents identified were virdiflorene (18.13 ± 0.46%) in root EO, (E)-β-caryophyllene (18.40 ± 0.60%) in trunk bark EO, and farnesyl acetone (15.26 ± 0.25%) in leaf EO. Notably, Cameroonian C. sylvaticus leaf EO exhibited a distinct and newly described chemotype with high levels of farnesyl acetone, β-copaene-4-α-ol, β-cadinene, α-humulene, and trans-longipinocarveol. In vitro testing revealed significant antiplasmodial activity against Plasmodium falciparum asexual (Pf3D7) and sexual (NF-54 strain) stages, with trunk bark EO showing the highest potency (IC50: 9.06 ± 2.15 µg/mL for Pf3D7 and 0.56 µg/mL for gametocytes). These findings support the traditional antimalarial use of C. sylvaticus and represent the first chemical profile and antiplasmodial efficacy report for its root and trunk bark EOs against both parasite stages. To the best of our knowledge, we also report for the first time the antiplasmodial activity of an EO that exerts significant activity against both the asexual and sexual forms of P. falciparum. [ABSTRACT FROM AUTHOR]

HERVs (Human endogenous retroviruses) are remnants of ancient exogenous retroviruses that have integrated into the human genome, particularly in germ-line cells. Among these, the envelope protein gene HERV-W env (Human endogenous retroviruses W family envelope protein), located on chromosome 7 and primarily expressed in the human placenta, has been closely linked to various neuropsychiatric disorders, including schizophrenia, as well as autoimmune diseases and cancer. Recent studies have highlighted the abnormal expression of cytokines as a key factor in the pathophysiology of schizophrenia. Notably, elevated serum levels of IL-1β (interleukin 1 beta) in schizophrenia, a cytokine associated with inflammation, are a characteristic feature of pyroptosis—a form of pro-inflammatory programmed cell death. Although previous research has observed significant upregulation of pyroptosis-related genes such as CASP1 (Caspase-1), NLRP3 (NLR family pyrin domain containing 3), and IL1B (interleukin 1 beta) in the serum of schizophrenia patients, and extensive neuron pyroptosis has been documented in various neuropsychiatric disorders, including Alzheimer's disease, epilepsy, and multiple sclerosis, the occurrence of neuron pyroptosis in schizophrenia remains uncertain. Furthermore, the mechanisms underlying pyroptosis in schizophrenia and its potential connection with HERV-W env have yet to be fully elucidated. In this study, we found that the expression levels of pyroptosis-related genes, specifically CASP1, GSDMD (Gasdermin D), and IL1B, were significantly elevated in patients with schizophrenia compared to healthy controls. Furthermore, our analysis revealed a strong positive correlation between HERV-W env expression and the levels of CASP1/GSDMD/IL1B in these patients. Experimental evidence further demonstrated that HERV-W env promoted the activation of Caspase-1 and the cleavage of Gasdermin D, leading to increased release of LDH (lactate dehydrogenase) and IL-1β. Importantly, inhibitors targeting NLRP3, CASP1, and GSDMD significantly reduced the releases of LDH and IL-1β induced by HERV-W env, whereas BID (BH3 interacting domain death agonist) inhibitors did not have a notable effect. This suggests that HERV-W env induces CASP1–GSDMD-dependent pyroptosis through the NLRP3–CASP1–GSDMD signaling pathway. As pyroptosis is increasingly recognized for its connection to neurodegenerative diseases, this study provides insights into the molecular mechanisms of neuronal pyroptosis mediated by the NLRP3 inflammasome in the context of HERV-W env. Additionally, it explores the potential facilitation of HERV-W env in the development of schizophrenia via pyroptosis, proposing that certain pyroptosis indicators could serve as potential biomarkers for schizophrenia. Based on our existing research results and the findings of previous researchers, we infer that HERV-W env acts as a bridge in the onset and progression of schizophrenia. Furthermore, HERV-W env may serve as a potential target for the clinical treatment of schizophrenia, suggesting that monoclonal antibody therapy targeting HERV-W env could represent a novel approach to managing this disease. [ABSTRACT FROM AUTHOR]

Germ cells are essential for fertility, embryogenesis, and reproduction. Germline development requires distinct types of germ granules, which contains RNA-protein (RNP) complexes, including germ plasm in embryos, piRNA granules in gonadal germ cells, and the Balbiani body (Bb) in oocytes. However, the regulation of RNP assemblies in zebrafish germline development are still poorly understood. Asz1 is a piRNA protein in Drosophila and mice. Zebrafish Asz1 localizes to both piRNA and Bb granules, with yet unknown functions. Here, we hypothesized that Asz1 functions in germ granules and germline development in zebrafish. We generated asz1 mutant fish to determine the roles of Asz1 in germ cell development. We show that Asz1 is dispensable for somatic development, but essential for germ cell and gonad development. asz1-/- fish developed exclusively as sterile males with severely underdeveloped testes that lacked germ cells. In asz1 mutant juvenile gonads, germ cells undergo extensive apoptosis, demonstrating that Asz1 is essential for germ cell survival. Mechanistically, we provide evidence to conclude that zygotic Asz1 is not required for primordial germ cell specification or migration to the gonad, but is essential during post-embryonic gonad development, likely by suppressing the expression of germline transposons. Increased transposon expression and mis-organized piRNA granules in asz1 mutants, argue that zebrafish Asz1 functions in the piRNA pathway. We generated asz1;tp53 fish to partially rescue ovarian development, revealing that Asz1 is also essential for oogenesis. We further showed that in contrast with piRNA granules, Asz1 is dispensable for Bb granule formation, as shown by normal Bb localization of Buc and dazl. By uncovering Asz1 as an essential regulator of germ cell survival and gonadogenesis in zebrafish, and determining its differential necessity in distinct germ granule types, our work advances our understanding of the developmental genetics of reproduction and fertility, as well as of germ granule biology. Author summary: Germ cells undergo a highly dynamic developmental program that begins in the early embryo and continues through juvenile and adult life. Identifying functional regulators and deciphering the developmental mechanisms of germ cells are critical for advancing our understanding of fertility and reproduction, as well as their associated diseases. Here, we identified Asz1 as an essential regulator of germ cell and gonad development in zebrafish. We demonstrate that zygotic Asz1 is dispensable for the specification and migration of primordial germ cells in the embryo, but is necessary for germ cell survival in the developing gonad, likely by protecting them from transposable elements. Upon loss of asz1, expression of germline transposons was induced, and piRNA granules were mis-organized, suggesting a conserved role for zebrafish Asz1 in the piRNA pathway. We further show that Asz1 is required for proper oogenesis. However, unlike RNA-protein (RNP) complexes of germ granules of the piRNA pathway, Asz1 was not required for RNP complexes of the Balbiani body in differentiating oocytes, revealing its differential necessity in distinct types of germ granules. In mice, Asz1 was shown to be essential for spermatogenesis but not oogenesis, but its functions in human gonads are unclear. Our work reports the functional requirements of Asz1 in both sexes in zebrafish, contributes to our knowledge of developmental reproduction biology, and sheds new light on the complexity of RNP complex assemblies in germ granules. [ABSTRACT FROM AUTHOR]

Testicular germ cell tumour (TGCT) is a malignancy with known inherited risk factors, affecting young men. We have previously identified several hundred differentially abundant circulating RNAs in pre-diagnostic serum from TGCT cases compared to healthy controls. In this study, we performed Weighted Gene Co-expression Network Analysis (WGCNA) on mRNA and miRNA data from these samples. Central genes (hub genes) enriched functional pathways, and regulatory feature prediction were identified for all TGCT subtypes together and according to histology. The TGCT susceptibility genes TEX14, NARS2, and G3BP2, were identified as hub genes in both seminoma and non-seminoma networks. We also identified UBCA1, RCC1, FMR1, OAS3, and UBE2W as hub genes associated with TGCT. The genes OAS3 and UBE2W have previously been associated with testicular dysgenesis. Furthermore, network module analysis indicated transcription factors for oestrogen-related receptors to have a potential role during development of TGCT. The overlap between mRNA network hub genes and TGCT susceptibility genes indicates a common role in TGCT development. [ABSTRACT FROM AUTHOR]

The fertile gonad includes cells of two distinct developmental origins: the somatic mesoderm and the germ line. How somatic and germ cells interact to develop and maintain fertility is not well understood. Here, using grafting experiments and transgenic reporter animals, we find that a specific part of the gonad--the germinal zone--acts as a sexual organizer to induce and maintain de novo germ cells and somatic gonads in the cnidarian Hydractinia symbiolongicarpus. Germ cells express a member of the transforming growth factor-β family, Gonadless (Gls), that induces gonad morphogenesis. Loss of Gls resulted in animals lacking gonads but having nonproliferative germ cells. We propose that primary germ cells drive gonad development though Gls secretion. The germinal zone in the newly formed gonad provides positive feedback to induce secondary germ cells by activating Tfap2 in resident pluripotent stem cells. The contribution of germ cell signaling to the patterning of somatic gonadal tissue may be a general animal feature. [ABSTRACT FROM AUTHOR]

In species with genetic sex determination (GSD), the sex identity of the soma determines germ cell fate. For example, in mice, XY germ cells that enter an ovary differentiate as oogonia, whereas XX germ cells that enter a testis initiate differentiation as spermatogonia. However, numerous species lack a GSD system and instead display temperature-dependent sex determination (TSD). In the red-eared slider turtle, Trachemys scripta, a TSD model species with a warm female promoting temperature (FPT) and cool male promoting temperature (MPT) system, temperature directly affects germ cell number. In this study, we examined whether temperature directly affects other aspects of germ cell differentiation/sex identity. We uncoupled temperature and the sexual fate of the gonad by incubating eggs at MPT and treating with 17ß-estradiol, a scheme that invariably produces ovaries. Through analysis of meiotic spreads, we showed that germ cells in FPT ovaries follow the typical pattern of initiating meiosis and progress through prophase I. However, in E2-induced ovaries that incubated at MPT, germ cells entered prophase I yet fail to exhibit synapsis. These results, combined with our single-cell transcriptome analysis, reveal a direct effect of temperature on germ cell sexual differentiation independent of its effect on the gonadal soma. These results imply that not all events of meiosis are under somatic control, at least not in this TSD species. [ABSTRACT FROM AUTHOR]

Background: Heterogeneous nuclear ribonucleoprotein M (HnRNPM) is a key splicing factor involved in various biological processes, including the epithelial‒mesenchymal transition and cancer development. Alternative splicing is widely involved in the process of spermatogenesis. However, the function of hnRNPM as a splicing factor during spermatogenesis remains unknown. Methods: The expression of hnRNPM in germ cells at different stages was detected by polymerase chain reaction, western blotting, a single-cell database, and chromosome spreading assays. Conditional hnRNPM knockout mice were generated to observe the development of testes and germ cells in male mice. Histological staining, immunofluorescence staining and transmission electron microscopy were used to observe the abnormal development of sperm from conditional hnRNPM-deficient mice. Coimmunoprecipitation and mass spectrometry analyses revealed the proteins that interact with hnRNPM. RNA sequencing was performed to analyse the different alternative splicing events in the testes of control and hnRNPM-deficient mice. Results: In this study, we revealed that hnRNPM is highly expressed in spermatocytes and round spermatids, with the exception of XY bodies and metaphase. Therefore, we generated a germ cell-specific hnRNPM conditional knockout mouse model to investigate the role of hnRNPM in spermatogenesis. A lack of hnRNPM led to male infertility under natural conditions. Male hnRNPM-deficient mice presented lower numbers of sperm, lower motility, significantly more malformed sperm and even tailless sperm. Moreover, we found that hnRNPM interacted with PTBP1 to collectively regulate the process of spermatogenesis. In addition, we found that hnRNPM deficiency caused 1617 different alternative splicing events, and we detected abnormal exon skipping events in Cep152, Cyld, Inpp4b and Cd59b. Conclusions: Together, our results suggest that hnRNPM regulates the alternative splicing of mRNAs during spermatogenesis by recruiting PTBP1 and is required for male mouse fertility. [ABSTRACT FROM AUTHOR]

Oocytes are the largest cell type in multicellular animals. Here, we show that mRNA transporter 4 (MTR4) is indispensable for oocyte growth and functions as part of the RNA surveillance mechanism, which is responsible for nuclear waste RNA clearance. MTR4 ensures the normal post-transcriptional processing of maternal RNAs, their nuclear export to the cytoplasm, and the accumulation of properly processed transcripts. Oocytes with Mtr4 knockout fail to accumulate sufficient and normal transcripts in the cytoplasm and cannot grow to normal sizes. MTR4-dependent RNA surveillance has a previously unrecognized function in maintaining a stable nuclear environment for the establishment of non-canonical histone H3 lysine-4 trimethylation and chromatin reorganization, which is necessary to form a nucleolus-like structure in oocytes. In conclusion, MTR4-dependent RNA surveillance activity is a checkpoint that allows oocytes to grow to a normal size, undergo nuclear and cytoplasmic maturation, and acquire developmental competence. [Display omitted] • RNA surveillance is responsible for the degradation of waste RNAs in the oocyte nucleus • RNA surveillance has a feedback function in maintaining a stable nuclear environment • MTR4 ensures the establishment of non-canonical H3K4me3 on gene bodies • MTR4-dependent RNA surveillance is a critical checkpoint for oocyte volume growth Wu et al. demonstrated the role of MTR4-mediated RNA surveillance in oocyte maturation and volume expansion, as well as mRNA processing and storage, nuclear organization, and protein accumulation. Disrupted RNA homeostasis resulted in abnormal chromatin structure, chaotic histone modifications, and cytoplasmic immaturity. [ABSTRACT FROM AUTHOR]

Reproductive system diseases have become a major health challenge facing humans, so extensive investigations are needed to understand their complex pathogenesis and summarize effective treatments. In the study of reproductive diseases, mice are the most commonly used animal model. However, the cost and time required to establish mouse animal models are high. The existing zebrafish model can solve this problem well. Zebrafish is an animal model with great application prospects and has lots of advantages, including high degree of genetic conservation with humans, short reproductive cycle, transparent embryos, and rapid growth, providing unique opportunities for high-throughput drug screening and identification of potential treatments. Researchers have successfully used chemical induction, physical damage, gene editing technology, etc., to induce reproductive system damage in zebrafish to study the biological processes related to its reproductive diseases. Therefore, in this review, the main models and related advantages of zebrafish in reproductive diseases are summarized, the pathological mechanisms of zebrafish as a reproductive disease model are clarified, and new perspectives and valuable insights are provided for the treatment of human reproductive diseases. The literature and data cited in the review are all from PubMed, covering important research results on zebrafish reproductive diseases in the past 10 years. [ABSTRACT FROM AUTHOR]

Objective Germline and somatic drivers are identified in 30% and 40% of pheochromocytomas and paragangliomas (PPGLs), respectively. In this study, we investigated the genetic landscape of PPGLs in a Brazilian cohort. Methods We studied 182 index patients with PPGLs (116 females and 66 males), comprising 118 pheochromocytoma and 70 paraganglioma cases. Our optimized sequencing strategy included SANGER sequencing, targeted next-generation sequencing panel, and whole-exome sequencing. Results Germline and somatic pathogenic or likely pathogenic variants in susceptibility genes were identified in 88 (48.4%) and 18 (10.4%) cases, respectively. SDHB was the most frequently affected gene, identified in 30 patients (16.5%), with a germline SDHB exon 1 deletion present in 46.7% of these cases. The Brazilian cohort exhibited a higher rate of germline diagnoses when compared to the European (31%), American (27%), and Chinese (21%) cohorts (P <.001). Five germline variants in new susceptibility genes were identified: (1) Three CHEK2 likely pathogenic or pathogenic variants (c.475T > C/p.Tyr159His; c.362G > A/p.Cys121Tyr; c.319 + 2T > A); and (2) Two BRCA2 pathogenic variants (c.3680_3681delTG/p.Leu1227fs and c.7806-2A > C). These variants are unreported in the Brazilian genomic variant repository. CHEK2 immunostaining was negative in the three tumors, with one case exhibiting CHEK2 loss of heterozygosity. Moreover, the prevalence of CHEK2 or BRCA2 pathogenic or likely pathogenic variants in our cohort was significantly higher compared to global population databases (P <.0001 and P =.0004, respectively). Conclusion Our cohort of PPGLs demonstrated a high frequency of germline diagnoses. Additionally, our findings suggest CHEK2 and BRCA2 as potential susceptibility genes for PPGLs. [ABSTRACT FROM AUTHOR]

Objective 17β-Hydroxysteroid dehydrogenase 3 deficiency (17β-HSDD) and 5α-reductase type 2 deficiency (5α-RD) are rare 46,XY differences of sex development (DSD). This study aims to enlarge the limited knowledge on long-term gonadal function and gonadal pathology in these conditions. Design Retrospective multicentre cohort study. Methods Data on phenotype, laboratory results, and hormone treatment were collected from patients aged ≥16 years at time of data collection with genetically confirmed 17β-HSDD and 5α-RD from 10 centres via the I-DSD Registry. If gonadectomy or gonadal biopsy had been performed, pathology reports and/or gonadal tissue or images were collected. Results All 16 patients with 17β-HSDD were raised female; 1 (6%) changed to male gender at age 14. Three females were treated with gonadotrophin-releasing hormone agonists (GnRHa) to prevent virilisation. Thirteen underwent gonadectomy at median age 8 (range 0-17). None had germ cell (pre)malignancies. Of 14 patients with 5α-RD, 10 (71%) were raised female. Five changed gender at age 7-23, of whom 4 to male gender. One was treated with GnRHa. Six underwent gonadectomy at median age 10 (range 0-31). None had germ cell (pre)malignancies. With gonads in situ, puberty spontaneously progressed. Three were treated with dihydrotestosterone. Conclusions A significant percentage of individuals with 17β-HSDD and 5α-RD changed gender, and some were treated with GnRHa to prevent virilisation before making a definitive decision about gonadectomy. When left in situ, spontaneous puberty occurs and germ cell (pre)malignancies seem uncommon at least until early adulthood. Together, these data support delaying a decision about gonadectomy until late adolescence in these conditions. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) selective trapping of particles and cells shows several potential applications such as reproductive cell selection, cell mechanics measurement, and in vivo rheology probes. Single-focused beams are a good candidate because of their simplicity, excellent selectivity, and strong trap. However, typical human cells in the water medium have the positive acoustic contrast factor and cannot be trapped in the focus of maximum intensity in a spherical focused beam as demonstrated recently [Gong and Baudoin, "Single beam acoustical tweezers based on focused beams: A numerical analysis of two-dimensional and three-dimensional trapping capabilities," Phys. Rev. Appl. 18, 044033 (2022)]. To achieve the 3D trapping and meanwhile keep the viability of cells, we propose to use a cell-friendly medium (i.e., iodixanol solution) to reverse the acoustic contrast factor to negative. Numerical experiments are conducted for the breast cancer cell (Michigan Cancer Foundation-7, MCF-7) with the computation of the three-dimensional (3D) acoustic radiation forces based on the angular spectrum method. It is shown that 3D trapping of MCF-7 in iodixanol medium with a single focused beam is possible, both in and beyond the Rayleigh regime. This work provides a solution to use a simple focused beam for 3D trapping of typical human cells, which may be beneficial to single-cell analysis, cellular phenotyping, precise assembly of different cells in tissue engineering, and controlled drug delivery. [ABSTRACT FROM AUTHOR]

Gonad histology complements research on the life history of fish species and provides greater accuracy and precision than macroscopic characterization of the gonad for determining patterns of oogenesis at the cellular level and maturation at the individual level. In a fishery context, histology improves estimation of mature and spawning stock biomass, identification of spawning seasonality and grounds, and preselection of specimens for calculation of annual fecundity. However, in most studies, only a single staining method (hematoxylin and eosin) has been used. In this study on 3 taxonomically diverse species, using 4 different staining methods of varying complexity (degree of counterstaining), we compared confidence levels in identification of 8 stages of oogenesis, the presence and level of degradation for postovulatory follicles, and atretic (vitellogenic) germ cells. As anticipated, the method involving the least expensive, monochromatic stain provided the lowest level of confidence, whereas the most expensive and complex counterstaining method provided the highest confidence level, with hematoxylin and eosin staining and another simple counterstaining method in between them. The effect of staining method was most evident for identifying cortical alveoli, which can affect estimation of size or age at maturity, and for identifying postovulatory follicles, which can affect estimation of spawning frequency. These results are broadly applicable for determining best practices. [ABSTRACT FROM AUTHOR]

Imbalances in testicular iron levels are linked to compromised sperm production and male infertility. Iron regulatory proteins (IRP) 1 and 2 play crucial roles in cellular iron regulation. We investigated the role of IRP1 on spermatogenesis using Irp1-deficient mice (Irp1-/-). Histological analysis of the testis of Irp1-/- mice revealed hypospermatogenesis with a significant reduction in the number of elongated spermatids and daily sperm production compared to wild-type (WT) mice. Flow cytometry of germ cells from WT and Irp1-/- mice showed reduction in spermatocytes and round and elongated spermatids in Irp1-/- mice, which was confirmed by histological and immunofluorescence quantification. Finally, stage VIII of spermatogenesis, crucial for spermatid maturation, was less frequent in Irp1-/- testicular cross-sections. Hypospermatogenesis worsened with age despite unchanged intratesticular iron levels. Mechanistically, this was due to increased oxidative stress indicated by elevated 8-Oxoguanine (8-OxoG) levels, a DNA lesion resulting from reactive oxygen species (ROS). Furthermore, bulk RNA-seq data indicated compromised DNA damage repair and cell cycle processes, including mitosis and meiosis in Irp1-/- mice, which may explain hypospermatogenesis. Our results suggest that IRP1 deletion leads to hypospermatogenesis due to impaired cell cycle progression, decreased DNA damage repair capacity, and oxidative damage. Altogether, this study uncovers a role for IRP1, independent of traditional mechanisms of iron regulation. [ABSTRACT FROM AUTHOR]

In modern times, a notable trend toward delayed childbearing has been observed in most developed countries. As a result, sperm aging and quality loss, as well as premature ovarian failure (POF), have emerged as major causes of infertility. The pathogenesis of sperm aging and POF is complex and has not been clearly elucidated. However, evidence from some studies has linked germ cell aging to epigenetic modifications. Epigenetics refers to the heritable changes in gene expression that occur in the absence of any alterations to the gene's nucleotide sequence. This paper systematically reviewed and analyzed the relevant literature to describe the relationship of DNA methylation, non-coding RNA regulation, histone modifications, chromatin remodeling, and RNA modifications with sperm aging and POF. In addition, we analyzed how sperm aging and POF can be mitigated via epigenetic interventions. This review could provide new therapeutic insights and guide strategies for improving sperm quality and ovarian function. [ABSTRACT FROM AUTHOR]

Stem cells are essential to repair and regenerate tissues, and often reside in a niche that controls their behavior. Here, we use the Drosophila testis niche, a paradigm for niche-stem cell interactions, to address the cell biological features that maintain niche structure and function during its steady-state operation. We report enrichment of Myosin II (MyoII) and a key regulator of actomyosin contractility (AMC), Rho Kinase (ROK), within the niche cell cortex at the interface with germline stem cells (GSCs). Compromising MyoII and ROK disrupts niche architecture, suggesting that AMC in niche cells is important to maintain its reproducible structure. Furthermore, defects in niche architecture disrupt GSC function. Our data suggest that the niche signals less robustly to adjacent germ cells yet permits increased numbers of cells to respond to the signal. Finally, compromising MyoII in niche cells leads to increased misorientation of centrosomes in GSCs as well as defects in the centrosome orientation checkpoint. Ultimately, this work identifies a crucial role for AMC-dependent maintenance of niche structure to ensure a proper complement of stem cells that correctly execute divisions. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigates how retinoic acid (RA), a key signaling molecule, influences the development of chicken primordial germ cells (PGC), which are precursors to sperm and eggs. The research aimed to understand how RA helps PGC transition from an immature, proliferative state to a differentiated, more mature state, eventually entering meiosis—a crucial step in germ cell development. Using cultured chicken PGC, the study found that RA changes their cell cycle, increasing the proportion of cells in the G1 phase. Some RA-treated cells even showed early signs of meiosis. Analysis of gene activity and chromatin structure revealed that RA strongly activates CYP26A1, a gene responsible for breaking down RA. This suggests PGC can self-regulate RA levels to delay premature meiosis, allowing proper maturation. Other identified genes, such as HNF1B and MYO1C, may also contribute to PGC differentiation. These findings provide new insights into how RA influences germ cell development and highlight potential molecular targets for further research. Retinoic acid (RA) plays a critical role in initiating meiosis in primordial germ cells (PGC), yet the specific mechanisms of its interaction with PGC remain unclear. In this study, we used an in vitro feeder-free culture system with chicken PGC as a model to explore the mechanisms by which RA induces the entry of PGC into meiosis. Results demonstrated that exogenous RA treatment altered the cell cycle distribution of PGC, significantly increasing the proportion of cells in the G1 phase and decreasing those in the G2 phase, suggesting that RA may promote the transition of PGC from proliferation to differentiation. Giemsa staining further revealed that chromosomes in a subset of RA-treated PGC exhibited meiotic characteristics. Through combined RNA-seq and ATAC-seq analyses, we identified that CYP26A1, a gene involved in RA degradation, was significantly upregulated in the RA-treated group, with enhanced accessibility in its chromatin regions. This finding suggests a robust mechanism for self-regulation of RA levels within PGC, indicating that CYP26A1 may play a pivotal role in the degradation of exogenous RA in chicken PGC. This study elucidated the effects of RA on chicken PGC and provided new insights into the role of RA in germ cell differentiation. [ABSTRACT FROM AUTHOR]

Simple Summary: Pathogenic and likely pathogenic germline variants in the BRCA1 and BRCA2 genes play a pivotal role in breast cancer development and progression and can determine the optimal risk-reducing strategies and personalized case management for the carriers of such variants. Our study aimed to evaluate the carrier status in a group of 58 patients who were referred to our center for genetic testing of the two genes, as well as establish a set of correlations between their genotypes and their clinical–pathological features. The study revealed that 15.5% of the patients harbored pathogenic variants in either of the two genes and that carriers of the BRCA1 pathogenic variants manifested a more aggressive tumor phenotype. These findings provide valuable insights that could be useful for the improvement in current national screening strategies and consolidate genetic testing as a valuable instrument in the personalized management of breast cancer. Background: Conditions associated with BRCA1/2 pathogenic (PVs) or likely pathogenic variants (LPVs) are often severe. The early detection of carrier status is ideal, as it provides options for effective case management. Materials and Methods: The study involved 58 patients with a personal and familial history of breast cancer (BC) who underwent genetic testing at the Regional Centre for Medical Genetics Dolj over a three-year period. An immunohistochemical panel (HER2, ER, PR, and Ki-67) was used to define the molecular subtypes of breast tumors. The AmpliSeq for Illumina BRCA Panel was used to evaluate germline variants in the BRCA1 and BRCA2 genes in patients with BC. The χ2 test and Fisher's exact test were used to compare the different parameters studied. Results: Our findings revealed that 15.5% of the patients carried either BRCA1 or BRCA2 PVs or LPVs. BRCA1 carriers had aggressive tumors whereas BRCA2 carriers had rather low-grade tumors. Conclusions: The study revealed that PVs in both BRCA genes have a significant frequency among BC patients in our region, and BRCA1 carriers tend to develop more aggressive tumors than carriers of BRCA2 PVs and patients with no germline PVs in either of the two genes. These observations could provide new epidemiologic data for this disease in our region and contribute further to the development of national screening strategies. [ABSTRACT FROM AUTHOR]

During all periods of male ontogenesis, physiological processes responsible for the correct functioning of reproductive organs and spermatogenesis are under the influence of various factors (neuro-humoral, genetic, and paratypical). Recently, the attention of researchers has increasingly turned to the study of epigenetic factors. In scientific publications, one can increasingly find references to the direct role of microRNAs, small non-coding RNAs involved in post-transcriptional regulation of gene expression, in the processes of development and functioning of reproductive organs. Although the role of microRNAs in the reproduction of mammals, including humans, has been intensively studied, this area of knowledge in birds remains under-researched and limited to single experiments. This is likely due to the unique features of embryogenesis and the structure of the avian reproductive system. This review summarizes the current state of knowledge on the role of microRNAs in avian reproduction. Insight into the molecular basis of spermatogenesis in Gallus gallus domesticus is provided. Data on the functions and mechanisms by which microRNAs influence the processes of growth, development, and formation of rooster germ cells that determine the necessary morphofunctional qualitative characteristics of mature spermatozoa are summarized. Particular attention is paid to miRNA biogenesis as an important step affecting the success of spermatogenesis, as well as the role of miRNAs in avian sex differentiation during early embryogenesis. The modern literature sources systematized in this review, revealing the questions about the role of miRNAs in the reproductive function of birds, create a theoretical basis and define new perspectives and directions for further research in this field. [ABSTRACT FROM AUTHOR]

Ovarian aging significantly impacts female fertility, with mitochondrial dysfunction emerging as a key factor. This study investigated the effects of recombinant follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on mitochondrial function and metabolism in aging female reproductive cells. Human granulosa cells (HGL5) were treated with FSH/LH or not. Mitochondrial function was assessed through various assays, including mitochondrial mass, membrane potential, ROS levels, and ATP production. Mitochondrial dynamics and morphology were analyzed using MitoTracker staining. Cellular respiration was measured using a Seahorse Bioenergetics Analyzer. Metabolic reprogramming was evaluated through gene expression analysis and metabolite profiling. In vivo effects were studied using aging mouse oocytes. FSH/LH treatment significantly improved mitochondrial function in aging granulosa cells, increasing mitochondrial mass and membrane potential while reducing ROS levels. Mitochondrial dynamics showed a shift towards fusion and elongation. Cellular respiration, ATP production, and spare respiratory capacity were enhanced. FSH/LH-induced favorable alterations in cellular metabolism, favoring oxidative phosphorylation. In aging mouse oocytes, FSH/LH treatment improved in vitro maturation and mitochondrial health. In conclusion, FSH/LH supplementation ameliorates age-related mitochondrial dysfunction and improves cellular metabolism in aging female reproductive cells. [ABSTRACT FROM AUTHOR]

Walleye pollock (Gadus chalcogrammus) is a commercially important species widely distributed in cold-water regions. We have been culturing this species artificially since 2015. The average embryo diameter was 1.43 ± 0.056 mm, and hatching occurred at 5 °C approximately 339 h post-fertilization. Gonadal development became visibly apparent at a body size of 10–15 cm after ~180 days, initially distinguishing ovaries with the development of germ cells, whereas testes were observable after further maturation. We discovered two intersexes from F1 and F2 generations, and one abnormal mature individual from F2. Morphologically, intersex walleye pollock exhibited distinct characteristics of ovary and testes, with male gonads visibly connected to the end of ovaries. In intersex walleye pollock aged 3–6 years, the gonads developed normally, and oocyte resorption was restricted to the area near the connections between testicular and ovarian tissues, with numerous atretic oocytes observed in the resorption zone. Primordial germ cells were found together in individuals who had not undergone spawning, indicating an abnormal maturation pattern. Although no significant differences in the gonadosomatic index were observed between intersex and normal individuals, further research on intersexuality is necessary to understand the reproductive development of this species and the health of offspring spawned by intersex individuals, which are rare. [ABSTRACT FROM AUTHOR]

RACGAP1 is a Rho-GTPase-activating protein originally discovered in male germ cells to inactivate Rac, RhoA and Cdc42 from the GTP-bound form to the GDP-bound form. GAP has traditionally been known as a tumor suppressor. However, studies increasingly suggest that overexpressed RACGAP1 activates Rac and RhoA in multiple cancers to mediate downstream oncogene overexpression by assisting in the nuclear translocation of signaling molecules and to promote cytokinesis by regulating the cytoskeleton or serving as a component of the central spindle. Contradictorily, it was also reported that RACGAP1 in gastric cancer could inactivate Rac and RhoA. In addition, studies have revealed that RACGAP1 can be a biomarker for prognosis, and its role in reducing doxorubicin sensitivity poses difficulties for treatment, while the current drug targets mainly focus on its downstream molecule. This article mainly reviews the expression regulation of RACGAP1 and its cancer-promoting functions through oncogene expression mediation and Rho-GTPase activation. [ABSTRACT FROM AUTHOR]

Organism health relies on cell proliferation, migration, and differentiation. These universal processes depend on cytoplasmic reorganization driven notably by the cytoskeleton and its force-generating motors. Their activity generates forces that mechanically agitate the cell nucleus and its interior. New evidence from reproductive cell biology revealed that these cytoskeletal forces can be tuned to remodel nuclear membraneless compartments, known as biomolecular condensates, and regulate their RNA processing function for the success of subsequent cell division that is critical for fertility. Both cytoskeletal and nuclear condensate reorganization are common to numerous physiological and pathological contexts, raising the possibility that mechanical remodeling of nuclear condensates may be a much broader mechanism regulating their function. Here, we review this newfound mechanism of condensate remodeling and venture into the contexts of health and disease where it may be relevant, with a focus on reproduction, cancer, and premature aging. [ABSTRACT FROM AUTHOR]

Pediatric suprasellar tumors represent a unique and intricate challenge in the landscape of pediatric neuro-oncology. We conducted an in-depth literature review, focusing on large clinical trials and major publications in pediatric suprasellar tumors, particularly craniopharyngiomas and germ cell tumors, to provide a comprehensive perspective on the challenges in the diagnosis, treatment, and molecular aspects of these tumors. Nestled within the critical confines of the suprasellar region, these tumors manifest against the backdrop of crucial growth and developmental processes. The suprasellar region, housing the pituitary gland and surrounding structures, plays a pivotal role in orchestrating hormonal regulation and growth. The emergence of tumors within this delicate terrain introduces a complex array of challenges, encompassing neurological, endocrinological, and developmental dimensions from damage to the hypothalamic-pituitary axis. This article provides a thorough exploration of pediatric craniopharyngiomas and germ cell tumors, elucidating their clinical presentations, treatment modalities, and outcomes. The focused analysis aims to deepen our understanding of these tumors by offering insights for refined clinical management and improved patient outcomes. [ABSTRACT FROM AUTHOR]

Skin and hair development is regulated by multitude of programs of activation and silencing of gene expression to maintain normal skin and hair follicle (HF) development, homeostasis, and cycling. Here, we have identified E74-like factor 5 (Elf5) transcription factor, as a novel regulator of keratinocyte proliferation and differentiation processes in skin. Expression analysis has revealed that Elf5 expression was localised and elevated in stem/progenitor cell populations of both the epidermis (basal and suprabasal) and in HF bulge and hair germ stem cell (SCs) compartments during skin and hair development and cycling. Expressional and functional analysis using RT-qPCR, western blot and colony forming assays, revealed that Elf5 plays an important role in regulating keratinocyte proliferation and differentiation processes as well as potentially determining cell fate by regulating the stem/progenitor cell populations in skin and HFs. These data will provide a platform for pharmacological manipulation of Elf5 in skin, leading to advancements in many areas of research, including stem cell, regenerative medicine, and ageing. [ABSTRACT FROM AUTHOR]

Research has shown that exposure to bisphenol A (BPA), a widely used plasticizer, can lead to meiotic errors, resulting in poor reproductive cell quality and infertility. Health-related concerns have prompted the search for BPA alternatives; however, evidence suggests that currently used BPA analogs, such as bisphenol S (BPS), may pose similar risks to human health. While the effects of BPA on female fertility are well documented, the impact of BPA exposure on sperm quality is poorly understood. To better understand the effects of bisphenol analogs on spermatogenesis, we synthesized a less investigated BPA analog, tetramethyl bisphenol F (TMBPF), and compared its reprotoxic potential to that of widely used BPA and BPS using C. elegans -based assays. We evaluated germ cell count, spermatid size, morphology, and activation in males treated with 0.5 mM ethanol-dissolved bisphenol analogs for 48 h as well as their cross-progeny number and viability. Our results indicated that all of the evaluated bisphenol analogs—BPA, BPS, and TMBPF—adversely affect male fertility to varying degrees. Whereas all three bisphenols reduced spermatid size, only BPA exposure resulted in impaired spermatid activation and significantly reduced brood size. In addition, a decrease in embryonic viability, suggestive of an increased incidence of sperm chromosomal aberrations, was observed following exposure to all of the tested bisphenols. Further investigation is necessary to fully elucidate the underlying mechanisms and implications of BPA, BPS, and TMBPF on spermatogenesis. [ABSTRACT FROM AUTHOR]

Background Approximately 2–20% of cutaneous melanomas (CMs) are diagnosed as amelanotic/hypopigmented melanoma (AHM) and represent a challenge for early diagnosis. Objectives To investigate loss-of-function mutations in key pigmentation genes in matched germline and AHM, as well as pigmented melanoma (PM), tumour DNA samples. Methods Analysis of clinical and histopathological characteristics – together with whole-exome sequencing data of 34 fresh frozen primary CMs, graded according to the amount of pigmentation present – was performed. Together with germline and somatic variant analysis, 30 samples had previously been analysed for copy number aberration (CNA) changes. This study focused on germline and somatic variants in the coding region of 16 genes known to be associated with albinism/hypopigmentation or variation in human pigmentation in all samples. Chromosomal regions encompassing these 16 genes were examined for DNA copy loss or gain. Results The finding that red hair-related MC1R and TYR R402Q loss-of-activity gene variant alleles and genotypes are associated with AHM was confirmed. Germline AHM-related gene variants were enriched in 70% (n = 7/10) of patients with AHM vs. 8% (n = 2/24) of those with PM. This surprisingly high frequency of rare germline variants in people with AHM constitutes the 'first hit' and confirms that those with AHM are more likely to be albinism allele carriers than individuals with PM. Next, in CNA analysis of each tumour sample, 50% (n = 4/8) of AHM samples with a pigmentation gene variant had loss of heterozygosity (LOH) in the region containing the corresponding gene and 25% (n = 2/8) had LOH in chromosomal regions of two AHM-related genes. Conclusions This study proposes that the likely molecular mechanism for the development of amelanogenesis in AHM is carriage of an albinism/hypopigmentation allele followed by LOH of the corresponding gene in the tumour. [ABSTRACT FROM AUTHOR]

The development of in vitro gametogenesis (IVG) in the mouse opened up unforeseen possibilities for assisted reproduction. The development of this technology to be used in cattle production could accelerate the rate of genetic selection by dramatically reducing the generation interval, while decreasing the environmental impact of livestock production as the need to grow animals in the process of genetic selection would be reduced or even eliminated. Although several steps of the process of IVG such as in vitro oocyte maturation and fertilization, and embryo production are already routinely performed in cattle, other steps of the system such as in vitro follicle and oocyte development are still rudimentary. The stable derivation of bovine pluripotent stem cells is the starting point without which IVG cannot be realized. However, producing a primordial germ cell and taking this cell through oogenesis and folliculogenesis in a dish will require a more detailed understanding of the milestones that need to be accomplished in vivo before they can be recapitulated in vitro. In particular, understanding the regulatory circuitry of germ cell specification in the embryo, the timing and events related to development of the germ cell program, and the factors necessary to make a competent egg, will need to be uncovered. Here, we review the process of IVG and provide a brief description of the current advances and bottlenecks related to in vitro oogenesis and folliculogenesis in cattle. Finally, we provide a brief comparison between mice and cows in this regard. Producing eggs and sperm in the laboratory is a novel technology that has the potential to reduce the impact of animal agriculture on our planet and accelerate the genetic improvement of cattle. However, there are many pieces of information that we still need to learn about how cows reproduce before we can take advantage of this technology. Recent scientific advances are helping fill these gaps and should lead us toward more efficient and sustainable agriculture. Image by Anna C. Denicol. This article belongs to the Collection: Proceedings of the Annual Conference of the International Embryo Technology Society, Fort Worth, TX, USA, 18–22 January 2025. [ABSTRACT FROM AUTHOR]

Surgical castration is a primary method for controlling male fertility, but it is impractical for large-scale population control of stray animals. Developing nanoparticle-mediated sterilants that induce cell apoptosis rather than necrosis is a complex and promising area of research. This study aimed to investigate the impact of intratesticular administration of alpha-mangostin encapsulated in nanostructured lipid carriers (AM-NLC) on testicular changes and any associated adverse effects over a 168-day observation period. Thirty-two healthy mature tomcats were enrolled. None of the cats treated with either AM-NLC (n = 28) or blank NLC (n = 4) exhibited noticeable complications related to pain or stress throughout the study, as assessed by clinical examination, blood profiles, and serum amyloid A levels. Histopathological analysis of AM-NLC treated cats revealed seminiferous epithelium degeneration, leading to defective tubules. Key findings included germ cell depletion, disorganized spermatogenic cells without spermatids in certain areas, apoptotic bodies, and intracytoplasmic vacuolization. The intertubular compartment showed no signs of inflammation, hyalinization, fibrosis, or necrosis. Despite widespread degeneration, some normal tubules were present in focal areas. The severity score of seminiferous tubule degeneration significantly increased from day 56 onwards (P < 0.05), suggesting a gradual and progressive compromise of the seminiferous epithelium. In contrast, testes from the blank-NLC group exhibited normal spermatogenesis. Overall, there were no significant changes in the volume of dissected testes, serum testosterone levels, or apoptotic index in AM-NLC-treated cats (P > 0.05). In conclusion, this study represents the first in vivo investigation of apoptotic-inducing agents as a novel nanomedicine-based antifertility compound for non-surgical castration in male animals. While the AM-NLC formulation proved safe for intratesticular administration, it failed to induce infertility in cats, as epididymal spermatozoa persisted throughout the study. Further research into alternative apoptosis-inducing nanomedicine sterilants remains both essential and challenging. [ABSTRACT FROM AUTHOR]

The gonadal primordial germ cells (PGCs) possess a unique state of pluripotency and X chromosome activity. However, extensive evidence indicates developmental variability in PGCs across different species. This study aims to evaluate the pluripotency status, specific gene expression patterns, and X chromosome reactivation (XCR) of pig gonadal PGCs. Single-cell RNA-seq revealed significant heterogeneity within the population of gonadal PGCs. Notably, these PGCs expressed high levels of pluripotency markers OCT4, PRDM14, and NANOG, while lacking SOX2 expression. Through the screening of marker genes and subsequent protein expression validation, we identified growth differentiation factor 3 (GDF3) as a specific surface marker for pig gonadal PGCs, facilitating their efficient purification for further study. Furthermore, analysis of gonadal PGCs demonstrated complete XCR. This was evidenced by the absence of repressive histone modifications (H3K27me3, H3K9me3, and H2AK119ub), the lack of X inactive specific transcript (XIST) RNA FISH signal, and the doubled expression of X-linked genes. Additionally, these PGCs expressed high levels of genes associated with epigenetic modification, chromatin remodeling, and XIST -associated RNA-binding. These factors likely play a crucial role in regulating pluripotency and X chromosome activity. In summary, this study reveals the heterogeneity in pig gonadal PGCs and identifies GDF3 as a specific surface marker. It also elucidates the expression patterns of pluripotency transcription factors and the events involved in XCR. • Pig gonadal PGCs exhibit obvious heterogeneity. • Female PGCs lack condensed XIST and repressive histone modifications punctate signals. • The GDF3 is a specific surface marker for gonadal PGCs. [ABSTRACT FROM AUTHOR]