Embryonic Development Research Articles

Advances in genetic research on Non-syndromic congenital joint synostosis

Congenital joint synostosis (CJS) is a functional impairment resulting from failure in joint morphogenesis during embryonic development. Clinically, it may be classified as syndromic (sCJS) and non-syndromic (nsCJS) disorders. Common sCJS include chromosomal disorders such as Klinefelter syndrome and single-gene disorders like Apert/Pfeiffer/Crouzon syndromes, Holt-Oram syndrome, Ehlers-Danlos syndrome, and Radial-ulnar synostosis with thrombocytopenia, presenting with multiple system/organ anomalies. By contrast, nsCJS manifest with only joint abnormalities, affecting one or multiple joints. This review has focused on human nsCJS and its genetic etiology. To date, variants in seven genes (NOG, GDF5, FGF9, GDF6, FGF16, SMAD6, and MECOM) have been identified as causative factors for nsCJS. This review has focused on such genes and provided a comprehensive review for the clinical phenotypes, genetic patterns, common variants, and underlying mechanisms associated with nsCJS based on a literature review. In addition, it has also analyzed other candidate genes for nsCJS within the context of relevant signaling pathways involved in joint morphogenesis.

Role of AMBRA1 in mitophagy regulation: emerging evidence in aging-related diseases.

Aging is a gradual and irreversible physiological process that significantly increases the risks of developing a variety of pathologies, including neurodegenerative, cardiovascular, metabolic, musculoskeletal, and immune system diseases. Mitochondria are the energy-producing organelles, and their proper functioning is crucial for overall cellular health. Over time, mitochondrial function declines causing an increased release of harmful reactive oxygen species (ROS) and DNA, which leads to oxidative stress, inflammation and cellular damage, common features associated with various age-related pathologies. The impairment of mitophagy, the selective removal of damaged or dysfunctional mitochondria by autophagy, is relevant to the development and progression of age-related diseases. The molecular mechanisms that regulates mitophagy levels in aging remain largely uncharacterized. AMBRA1 is an intrinsically disordered scaffold protein with a unique property of regulating the activity of both proliferation and autophagy core machineries. While the role of AMBRA1 during embryonic development and neoplastic transformation has been extensively investigated, its functions in post-mitotic cells of adult tissues have been limited due to the embryonic lethality caused by AMBRA1 deficiency. Recently, a key role of AMBRA1 in selectively regulating mitophagy in post-mitotic cells has emerged. Here we summarize and discuss these results with the aim of providing a comprehensive view of the mitochondrial roles of AMBRA1, and how defective activity of AMBRA1 has been functionally linked to mitophagy alterations observed in age-related degenerative disorders, including muscular dystrophy/sarcopenia, Parkinson diseases, Alzheimer diseases and age-related macular degeneration.

The vacuolar sulfate transporter PsSULTR4 is a key determinant of seed yield and protein composition in pea.

Pea is a grain legume crop with a high potential to accelerate the food transition due to its high seed protein content and relatively well-balanced amino acid composition. The critical role of external sulfur (S) supply in determining seed yield and seed quality in pea makes it essential to understand the impact of whole plant S management on the trade-off between these two traits. Here, we investigated the physiological relevance of vacuolar sulfate remobilization by targeting PsSULTR4, the only pea sulfate transporter showing substantial similarity to the vacuolar sulfate exporter AtSULTR4;1. Five mutations in PsSULTR4 were identified by TILLING (Targeting Induced Local Lesions IN Genomes), two of which, a loss of function (W78*) and a missense (E568K), significantly decreased seed yield under S deprivation. We demonstrate that PsSULTR4 triggers S distribution from source tissues, especially lower leaves, to reproductive organs to maintain seed yield under S deficiency. Under sufficient S supply, sultr4 seeds display lower levels of the S-rich storage protein PA1 at maturity. They also overaccumulate sulfate in the endosperm at the onset of seed filling. These findings uncover a role of PsSULTR4 in the remobilization of vacuolar sulfate during embryo development, allowing the efficient synthesis of S-rich proteins. Our study uncovers that PsSULTR4 functions (i) in source tissues to remobilize stored vacuolar sulfate for seed production under low S availability and (ii) in developing seeds well supplied with S to fine-tune sulfate remobilization from the endosperm as a critical control point for storage activities in the embryo.

Catalytic activity of Setd2 is essential for embryonic development in mice: establishment of a mouse model harboring patient-derived Setd2 mutation.

SETD2 is the only enzyme responsible for transcription-coupled histone H3 lysine 36 trimethylation (H3K36me3). Mutations in SETD2 cause human diseases including cancer and developmental defects. In mice, Setd2 is essential for embryonic vascular remodeling. Given that many epigenetic modifiers have recently been found to possess noncatalytic functions, it is unknown whether the major function(s) of Setd2 is dependent on its catalytic activity or not. Here, we established a site-specific knockin mouse model harboring a cancer patient-derived catalytically dead Setd2 (Setd2-CD). We found that the essentiality of Setd2 in mouse development is dependent on its methyltransferase activity, as the Setd2CD/CD and Setd2-/- mice showed similar embryonic lethal phenotypes and largely comparable gene expression patterns. However, compared with Setd2-/-, the Setd2CD/CD mice showed less severe defects in allantois development, and single-cell RNA-seq analysis revealed differentially regulated allantois-specific 5' Hoxa cluster genes in these two models. Collectively, this study clarifies the importance of Setd2 catalytic activity in mouse development and provides a new model for comparative study of previously unrecognized Setd2 functions.

Characterizing seed dormancy in Epimedium brevicornu Maxim.: Development of novel chill models and determination of dormancy release mechanisms by transcriptomics

PurposeEpimedium brevicornu Maxim. is a perennial persistent C3 plant of the genus Epimedium Linn. in the family Berberaceae that exhibits severe physiological and morphological seed dormancy.We placed mature E. brevicornu seeds under nine stratification treatment conditions and explored the mechanisms of influence by combining seed embryo growth status assessment with related metabolic pathways and gene co-expression analysis.ResultsWe identified 3.9 °C as the optimum cold-stratification temperature of E. brevicornu seeds via a chilling unit (CU) model. The best treatment was variable-temperature stratification (10/20 °C, 12/12 h) for 4 months followed by low-temperature stratification (4 °C) for 3 months (4-3). A total of 63801 differentially expressed genes were annotated to 2587 transcription factors (TFs) in 17 clusters in nine treatments (0-0, 0-3, 1-3, 2-3, 3-3, 4-3, 4-2, 4-1, 4-0). Genes specifically highly expressed in the dormancy release treatment group were significantly enriched in embryo development ending in seed dormancy and fatty acid degradation, indicating the importance of these two processes. Coexpression analysis implied that the TF GRF had the most reciprocal relationships with genes, and multiple interactions centred on zf-HD and YABBY as well as on MYB, GRF, and TCP were observed.ConclusionIn this study, analyses of plant hormone signal pathways and fatty acid degradation pathways revealed changes in key genes during the dormancy release of E. brevicornu seeds, providing evidence for the filtering of E. brevicornu seed dormancy-related genes.

Monoamine oxidases activity maintains endometrial monoamine homeostasis and participates in embryo implantation and development

BackgroundMonoamine oxidases (MAOs) is an enzyme that catalyzes the deamination of monoamines. The current research on this enzyme is focused on its role in neuropsychiatric, neurodevelopmental, and neurodegenerative diseases. Indeed, MAOs with two isoforms, namely, A and B, are located on the outer mitochondrial membrane and are widely distributed in the central nervous system and peripheral tissues. Several reports have described periodic changes in the levels of this enzyme in the human endometrial tissue.ResultsThe novel role of MAOs in endometrial receptivity establishment and embryonic development by maintaining monoamine homeostasis was investigated in this study. MAOs activity was observed to be enhanced during the first trimester in both humans and mice under normal conditions. However, under pathological conditions, MAOs activity was reduced and was linked to early pregnancy failure. During the secretory phase, the endometrial stromal cells differentiated into decidual cells with a stronger metabolism of monoamines by MAOs. Excessive monoamine levels cause monoamine imbalance in decidual cells, which results in the activation of the AKT signal, decreased FOXO1 expression, and decidual dysfunction.ConclusionsThe findings suggest that endometrial receptivity depends on the maintenance of monoamine homeostasis via MAOs activity and that this enzyme participates in embryo implantation and development.

Experimental Varicocele Impairs DNA Methylation and Demethylation in Germ Cells, TESE, and Epididymal Spermatozoa, Impacting Active DNA Demethylation in Zygotes.

Varicocele causes infertility. The current study has investigated the impact of experimental varicocele on DNA methylation, demethylation, and damage in the germ cells, TESE-derived and epididymal spermatozoa. Moreover, the results were compared between epidydimal and TESE-derived spermatozoa. Finally, the varicocele-induced effect on active DNA demethylation (ADD) of male pronucleus and pre-implantation embryo development was assessed. The mature male rats were divided into control, control-sham (undergone simple laparotomy), and experimental varicocele-induced groups (n = 6/each group). The left renal vein semi-ligation was considered to induce varicocele. The expression levels of DNA methyltransferase 1 (DNMT1) and ten-eleven-translocation proteins (TET1, 2, 3), and global DNA methylation in testicular tissue, TESE, and epididymis-derived spermatozoa, and the ADD in zygotes male pronucleus as well as pre-implantation embryo development were assessed. The expression levels of DNMT1 and TET1, 2, 3 in testicles, TESE, and epididymis-derived spermatozoa were decreased in the varicocele group compared to the control and control-sham groups. The TESE-derived spermatozoa exhibited higher DNMT1, higher DNMT1, and TET 1, 2, and no change in TET3 expression compared to epididymis-derived spermatozoa. The varicocele group represented lower DNA methylation in the testicles, TESE-derived and epididymal spermatozoa, higher 5mC+ signal in male pronucleus, and a lower pre-implantation embryo development compared to control and control-sham rats. The TESE-derived spermatozoa exhibited higher 5mC protein expression compared to epididymal spermatozoa. In conclusion, varicocele can negatively impact the DNA methylation/demethylation processes impairing spermatogenesis and leading to fertilization failure, which may ultimately result in a decrease in embryo development by increasing susceptibility to DNA damage.

Water-accommodated fractions of heavy and light oils impact DNA integrity, embryonic development, and immune system of Japanese medaka at early life stages.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous contaminants generally found in complex mixtures. PAHs are known to cause pleiotropic effects on living organisms, including developmental defects, mutagenicity, carcinogenicity and immunotoxicity, and endocrine disruptions. The main goal of this study is to evaluate the toxicity of water-accommodated fractions (WAFs) of oils in two life stages of the Japanese medaka, larvae and juveniles. The deleterious effects of an acute exposure of 48h to two WAFs from Arabian light crude oil (LO) and refined oil from Erika (HO) were analyzed in both stages. Relevant endpoints, including ethoxy resorufin-O-deethylase (EROD) activity, DNA damage (Comet assay), photomotor response, and sensitivity to nervous necrosis virus (NNV) infection, were investigated. Larvae exposed to both oil WAFs displayed a significant induction of EROD activity, DNA damage, and developmental anomalies, but no behavioral changes. Deleterious effects were significantly increased following exposure to 1 and 10μg/L of LO WAFs and 10μg/L of HO WAFs. Larval infection to NNV induced fish mortality and sharply reduced reaction to light stimulation. Co-exposure to WAFs and NNV increased the mortality rate, suggesting an impact of WAFs on fish defense capacities. WAF toxicity on juveniles was only observed following the NNV challenge, with a higher sensitivity to HO WAFs than to LO WAFs. This study highlighted that environmentally realistic exposure to oil WAFs containing different compositions and concentrations of oil generated high adverse effects, especially in the larval stage. This kind of multi-marker approach is particularly relevant to characterize the toxicity fingerprint of environmental mixtures of hydrocarbons and PAHs.

New Interpretations for Sprouting, Intussusception, Ansiform, and Coalescent Types of Angiogenesis

Angiogenesis, or the development of blood vessels by growing from already-formed vessels, is observed in embryonic development, physiological cyclical processes such as wound healing, the encapsulation of foreign bodies, tumor growth, and some other situations. In this review, we analyze the cellular mechanisms of angiogenesis, namely, angiogenesis by sprouting, ansiform (by loop formation) angiogenesis, coalescent angiogenesis, and angiogenesis by intussusception (splitting the capillary into two channels). The analysis of data revealed a lot of unanswered questions and contradictions. Here, we propose several new models of angiogenesis explaining these contradictions.

Advancement of DDR1 and DDR2 Inhibitors: Therapeutic Potential of Bioactive Compounds, Designing Strategies, and Structure‐Activity Relationship (SAR)

AbstractDDR1 and DDR2 are nonintegrin collagen receptors in the receptor tyrosine kinase family. Both DDRs bind to various collagen types and perform crucial functions in embryo development. DDRs are different from other receptor tyrosine kinases due to their interaction with extracellular matrix components and unusual activation kinetics. DDR regulates cell migration, survival, proliferation, differentiation, and extracellular matrix remodeling. Dysregulated DDR function is linked to the advancement of several human illnesses, including fibrosis, arthritis, neurodegenerative diseases, and cancer. DDRs play a vital role in disease progression and development. Therefore, the use of DDR inhibitors represents a promising therapeutic strategy, particularly for disorders with limited therapy alternatives. In recent years, DDRs have been regarded as attractive targets for drug development, as evidenced by a significant rise in research in this field. The current review illustrates about recent advancement of small molecules, their designing strategies and structure‐activity relationship. The DDR inhibitors can contain various core structures such as pyrimidine, phthalazine, pyrazole, pyrazine, imidazo[1,2‐a]sspyrazine, quinazoline, and thieno[3,2‐b]pyridin‐7‐yl derivatives. Furthermore, based on the constructive analysis of the published derivatives, we found that the majority of the powerful compounds have a similar scaffold (amide linker, hydrophobic tail, hinge binder with or without spacer). Among the different literature, the most potent compounds 4 (imidazo[1,2‐a]pyrazine), 5 (pyridine), 19 (pyridine), and 24 (quinazoline) displayed potent activity against DDR1 with IC50 values ranging from 2.26 – 4.67 nM, while DDR2 IC50 values ranging from 3.2 – 7.29 nM. This approach will help medicinal chemists to refine and develop novel small molecules targeting DDR1 and DDR2.

Drinking water quality impacts oocyte viability and embryo development

Normal reproductive function and fertility is considered a “sixth vital sign” because disruptions to this sensitive physiological system can forewarn other health issues, including exposure to environmental toxicants. We found that female mice exhibited profound loss of embryos during pre-implantation and fetal development coincident with a change to the source of their drinking water. When female mice were provided with tap water from the building in which they were housed (Water 2), instead of tap water from a neighboring building which was their previous supply (Water 1), ovulated oocytes were degenerated or had impaired meiotic maturation, and failed to form embryos. The harmful effects of Water 2 exposure were not reversible even following a recovery period; however, carbon-filtration of Water 2 removed the toxic contaminant. Water composition analysis to identify the responsible toxicant(s) found that trace elements were present at expected levels and phthalates were undetectable. Per- and Poly-fluoroalkyl Substances (PFAS), a family of persistent organic pollutants were detected at ∼4 ng/L. To investigate further, female mice were given drinking water categorized by level of PFAS contamination (0.6 ng/L, 2.8 ng/L, or 4.4 ng/L) for 9 weeks. Compared to mice consuming purified MilliQ water, mice consuming PFAS-contaminated water had decreased oocyte quality, impaired embryogenesis and reduced cell numbers in blastocysts. PFAS concentration in the drinking water was negatively correlated with oocyte viability. Importantly, the levels of PFAS detected in the tap water are within current “safe level” guidelines, and further research is needed to determine whether PFAS are responsible for the observed reproductive toxicity. However, this research demonstrating that water deemed suitable for human consumption has detrimental effects on mammalian embryo development has important implications for public health and water quality policies.

Abnormal amino acid synthesis and glutathione metabolism may affect PCOS blastocyst development: an examination of in vitro mouse blastocysts model utilizing RNA-sequencing

BackgroundExtensive research has been conducted on embryonic developmental disorders linked to Polycystic Ovary Syndrome (PCOS), a pathological condition that affects 5−10% of women and is characterized by irregularities in the menstrual cycle and infertility. By employing RNA sequencing (RNA-seq), we performed an in-depth investigation of PCOS-related changes in gene expression patterns at the mouse blastocyst stage.MethodsThe zygotes of female B6D2 mice were obtained and then differentiated into blastocysts in K + Simplex Optimised Medium (KSOM) cultures containing exo-NC (negative control for exosomes) or exo-LIPE-AS1 (a novel exosomal marker of PCOS). Subsequently, blastocysts were collected for RNA-seq. The bioinformatics was performed to analyze and compare the differences of gene expression profile between blastocysts of control and PCOS group.ResultsThere were 1150 differentially expressed genes (DEGs) between the two groups of mouse blastocysts; 243 genes were upregulated and 907 downregulated in the blastocysts of the exo-LIPE-AS1 group compared to those of the exo-NC group. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the genes involved in amino acid synthesis and glutathione metabolic pathways were down-regulated in exo-LIPE-AS1 group.ConclusionThis study has revealed that blastocyst developmental retardation may be associated with the downregulation of amino acid synthesis and glutathione metabolism, which may affect energy metabolism, biosynthesis, cellular osmotic pressure, antioxidant synthesis, ROS clearance or mitochondrial function, and ultimately cause blastocyst cell development abnormalities. Our research offers encouraging data on the mechanisms underlying aberrant embryonic development in patients with PCOS as well as potential treatment strategies.

Dysregulation of Transposon Transcription Profiles in Cancer Cells Resembles That of Embryonic Stem Cells

Transposable elements (TEs) comprise a substantial portion of the mammalian genome, with potential implications for both embryonic development and cancer. This study aimed to characterize the expression profiles of TEs in embryonic stem cells (ESCs), cancer cell lines, tumor tissues, and the tumor microenvironment (TME). We observed similarities in TE expression profiles between cancer cells and ESCs, suggesting potential parallels in regulatory mechanisms. Notably, four TE RNAs (HERVH, LTR7, HERV-Fc1, HERV-Fc2) exhibited significant downregulation across cancer cell lines and tumor tissues compared to ESCs, highlighting potential roles in pluripotency regulation. The strong up-regulation of the latter two TEs (HERV-Fc1, HERV-Fc2) in ESCs has not been previously demonstrated and may be a first indication of their role in the regulation of pluripotency. Conversely, tandemly repeated sequences (MSR1, CER, ALR) showed up-regulation in cancer contexts. Moreover, a difference in TE expression was observed between the TME and the tumor bulk transcriptome, with distinct dysregulated TE profiles. Some TME-specific TEs were absent in normal tissues, predominantly belonging to LTR and L1 retrotransposon families. These findings not only shed light on the regulatory roles of TEs in both embryonic development and cancer but also suggest novel targets for anti-cancer therapy. Understanding the interplay between cancer cells and the TME at the TE level may pave the way for further research into therapeutic interventions.

HÁBITOS ALIMENTARES DURANTE A GESTAÇÃO: UMA INVESTIGAÇÃO SOBRE A POSSÍVEL INFLUÊNCIA NO DESENVOLVIMENTO DO TRANSTORNO DO ESPECTRO AUTISTA (TEA)

Autism Spectrum Disorder (ASD) is a complex neurological condition that impacts social, communicative, and behavioral development. This study investigates the relationship between the dietary habits of pregnant women and the development of ASD in their children, focusing on folic acid (vitamin B9) supplementation. Previous studies suggest that folic acid is essential for neural tube closure during embryonic development, but its excess may be related to an increased risk of autism. The study uses a qualitative methodology and a comprehensive literature review, analyzing articles published between 2017 and 2024 in databases such as SciELO, PubMed, Google Scholar, and Web of Science. The literature review highlights the importance of epigenetic regulation in the neurological development of ASD, influenced by adequate levels of folic acid during pregnancy. However, there is a significant gap in the complete understanding of this relationship, especially regarding the interaction of several nutrients and their impacts on neurodevelopment. In conclusion, although folic acid supplementation is an essential public health measure to prevent neural tube defects, careful monitoring is crucial to avoid potential risks of autism. The research highlights the need for further studies to elucidate the exact mechanisms and identify reliable biomarkers that can aid in early diagnosis and preventive interventions to improve health outcomes in children at risk of developing ASD.

Pluripotent stem cell-derived organoids: A brief history of curiosity-led discoveries.

Organoids are quickly becoming an accepted model for understanding human biology and disease. Pluripotent stem cells (PSC) provide a starting point for many organs and enable modeling of the embryonic development and maturation of such organs. The foundation of PSC-derived organoids can be found in elegant developmental studies demonstrating the remarkable ability of immature cells to undergo histogenesis even when taken out of the embryo context. PSC-organoids are an evolution of earlier methods such as embryoid bodies, taken to a new level with finer control and in some cases going beyond tissue histogenesis to organ-like morphogenesis. But many of the discoveries that led to organoids were not necessarily planned, but rather the result of inquisitive minds with freedom to explore. Protecting such curiosity-led research through flexible funding will be important going forward if we are to see further ground-breaking discoveries.

From follicle to blastocyst: microRNA-34c from follicular fluid-derived extracellular vesicles modulates blastocyst quality

BackgroundWithin the follicular fluid, extracellular vesicles (EVs) guide oocyte growth through their cargo microRNAs (miRNAs). Here, we investigated the role of EVs and their cargo miRNAs by linking the miRNAs found in EVs, derived from the fluid of an individual follicle, to the ability of its oocyte to become a blastocyst (competent) or not (non-competent).MethodsBovine antral follicles were dissected, categorized as small (2–4 mm) or large (5–8 mm) and the corresponding oocytes were subjected to individual maturation, fertilization and embryo culture to the blastocyst stage. Follicular fluid was pooled in 4 groups (4 replicates) based on follicle size and competence of the corresponding oocyte to produce a blastocyst. Follicular fluid-derived EVs were isolated, characterized, and subjected to miRNA-sequencing (Illumina Miseq) to assess differential expression (DE) in the 4 groups. Functional validation of the effect of miR-34c on embryo development was performed by supplementation of mimics and inhibitors during in vitro maturation (IVM).ResultsWe identified 16 DE miRNAs linked to oocyte competence when follicular size was not considered. Within the large and small follicles, 46 DE miRNAs were driving blastocyst formation in each group. Comparison of EVs from competent small and large follicles revealed 90 DE miRNAs. Cell regulation, cell differentiation, cell cycle, and metabolic process regulation were the most enriched pathways targeted by the DE miRNAs from competent oocytes. We identified bta-miR-34c as the most abundant in follicular fluid containing competent oocytes. Supplementation of miR-34c mimic and inhibitor during IVM did not affect embryo development. However, blastocyst quality, as evidenced by higher cell numbers, was significantly improved following oocyte IVM in the presence of miR-34c mimics, while miR-34c inhibitors resulted in the opposite effect.ConclusionThis study demonstrates the regulatory effect of miRNAs from follicular fluid-derived EVs on oocyte competence acquisition, providing a further basis for understanding the significance of miRNAs in oocyte maturation and embryonic development. Up-regulation of miR-34c in EVs from follicular fluid containing competent oocytes and the positive impact of miR-34c mimics added during IVM on the resulting blastocysts indicate its pivotal role in oocyte competence.

Modulation of mechanosensitive genes during embryonic aortic arch development.

Early embryonic aortic arches (AA) are a dynamic vascular structures that are in the process of shaping into the great arteries of cardiovascular system. Previously, a time-lapsed mechanosensitive gene expression map was established for AA subject to altered mechanical loads in the avian embryo. To validate this map, we investigated effects on vascular microstructure and material properties following the perturbation of key genes using an in-house microvascular gene knockdown system. All siRNA vectors show a decrease in the expression intensity of desired genes with no significant differences between vectors. In TGFβ3 knockdowns, we found a reduction in expression intensities of TGFβ3 (≤76%) and its downstream targets such as ELN (≤99.6%), Fbn1 (≤60%), COL1 (≤52%) and COL3 (≤86%) and an increase of diameter in the left AA (23%). MMP2 knockdown also reduced expression levels in MMP2 (≤30%) and a 6-fold increase in its downstream target COL3 with a decrease in stiffness of the AA wall and an increase in the diameter of the AA (55%). These in vivo measurements were confirmed using immunohistochemistry, western blotting and a computational growth model of the vascular extracellular matrix (ECM). Localized spatial genetic modification of the aortic arch region governs the vascular phenotype and ECM composition of the embryo and can be integrated with mechanically-induced congenital heart disease models.

A CRISPR/RfxCas13d-mediated strategy for efficient RNA knockdown in mouse embryonic development.

The growing variety of RNA classes, such as mRNAs, lncRNAs, and circRNAs, plays pivotal roles in both developmental processes and various pathophysiological conditions. Nonetheless, our comprehension of RNA functions in live organisms remains limited due to the absence of durable and effective strategies for directly influencing RNA levels. In this study, we combined the CRISPR-RfxCas13d system with sperm-like stem cell-mediated semi-cloning techniques, which enabled the suppressed expression of different RNA species. This approach was employed to interfere with the expression of three types of RNA molecules: Sfmbt2 mRNA, Fendrr lncRNA, and circMan1a2(2,3,4,5,6). The results confirmed the critical roles of these RNAs in embryonic development, as their loss led to observable phenotypes, including embryonic lethality, delayed embryonic development, and embryo resorption. In summary, our methodology offers a potent toolkit for silencing specific RNA targets in living organisms without introducing genetic alterations.

Application of genome tagging technology in elucidating the function of sperm-specific protein 411 (Ssp411).

The genome tagging project (GTP) plays a pivotal role in addressing a critical gap in the understanding of protein functions. Within this framework, we successfully generated a human influenza hemagglutinin-tagged sperm-specific protein 411 (HA-tagged Ssp411) mouse model. This model is instrumental in probing the expression and function of Ssp411. Our research revealed that Ssp411 is expressed in the round spermatids, elongating spermatids, elongated spermatids, and epididymal spermatozoa. The comprehensive examination of the distribution of Ssp411 in these germ cells offers new perspectives on its involvement in spermiogenesis. Nevertheless, rigorous further inquiry is imperative to elucidate the precise mechanistic underpinnings of these functions. Ssp411 is not detectable in metaphase II (MII) oocytes, zygotes, or 2-cell stage embryos, highlighting its intricate role in early embryonic development. These findings not only advance our understanding of the role of Ssp411 in reproductive physiology but also significantly contribute to the overarching goals of the GTP, fostering groundbreaking advancements in the fields of spermiogenesis and reproductive biology.

Analysis of factors influencing pregnancy and its outcomes in women undergoing in vitro fertilization-embryo transfer/frozen embryo transfer cycles: A retrospective study.

The relationship between clinical outcomes and various factors influencing pregnancy was analyzed to provide reference data for patients and clinicians when selecting embryo transfer protocols. This was a retrospective study of 1309 transfer cycles between June 1, 2018, and May 1, 2023, in the Reproductive Medicine Center. Univariate analysis was performed on various factors that may have affected pregnancy outcomes, and further regression analysis was performed on those factors found by univariate analysis to correlate positively with clinical pregnancy outcomes. Finally, the embryo transfer schemes were compared based on the analysis results. The results showed that the stage of embryonic development significantly affected pregnancy outcomes after transplantation (P < .01, 95% confidence interval: 2.554 [1.958-3.332]). There was no significant difference in the pregnancy rate between 1 high-quality blastocyst transfer and 2 cleavage-stage embryos or blastocyst transfer (64.22% vs 70.11%, P = .439); however, the rate of multiple pregnancies after 1 high-quality blastocyst transfer was close to the rate of natural conception. These data show that the transfer of single high-quality blastocysts can significantly reduce the multiple pregnancy rate while ensuring an ideal pregnancy rate, which can be used as a reference for planning the first transplantation in patients with good prognoses.