Mature Follicles Research Articles

Regulatory signatures involved in the cell cycle pathway contribute to egg production heterosis in chicken

BackgroundCrossbreeding is widely promoted as an efficient strategy to improve the productivity in agriculture. The molecular mechanism underlying heterosis for egg production is always intriguing in chicken. The transcriptional dynamic changes play a crucial role in the formation of heterosis, but little is known for the egg production traits.ResultsIn present study, we measured the continuous manifestation of heterosis ranging from 2.67% to 10.24% for egg number in the crossbreds generated by reciprocal crossing White Leghorn and Beijing You chicken. The high-quality transcriptomes of ovary for purebreds (WW and YY) and crossbreds (WY and YW) in 5 laying stages were sequenced and integrated to identify regulatory networks relevant to the heterosis. We found highly conserved transcriptional features among 4 genetic groups. By using weighted gene co-expression network analysis (WGCNA), we obtained multiple gene co-expression modules that were significantly correlated with egg number for each group. The common KEGG pathways including apelin signaling pathway, cell cycle, ribosome, spliceosome and oxidative phosphorylation, were screened for the 2 crossbreds. Then, we identified consensus co-expression modules (CMs) that showed divergent expression pattern among crossbred (WY or YW) and purebreds (WW and YY). The hub genes of CMs were again overrepresented in the cell cycle pathway, and the crossbreds exhibited temporally complementary dominance of hub genes in the 5 laying stages. These results suggested that the crossbreds inherited from both parents to maintain the ovary function by cell cycle-related genes, contributing to the persistent heterosis for egg production. Furthermore, the dominant genes including MAD2L1, CHEK2 and E2F1 were demonstrated to function in ovarian follicle development and maturation and could be the candidate genes for egg production heterosis.ConclusionOur study characterized the dynamic profile of genome-wide gene expression in ovary and highlighted the role of dominant expression of cell cycle pathway genes in heterosis. These findings provided new insights for the molecular mechanism of egg production heterosis, which would facilitate the rational choice of suitable parents for producing crossbred chickens with higher egg production.

The hematopoietic function, histological characteristics, and transcriptome profiling of Wanxi white geese ovary during nesting and late-laying stages.

Despite several factors influencing reproduction in geese, but the precise molecular mechanisms of egg cessation are not fully understood. In the present study, the hematopoietic parameters and serum hormone levels in Wanxi white geese were analyzed. RNA-Seq was utilized to identify the differentially expressed mRNAs (DEGs) and lncRNAs (DE lncRNAs) in the ovarian tissues associated with nesting in geese during the late-laying and nesting periods. Triglyceride (TG) and alkaline phosphatase (ALP) levels were higher in late-laying geese, while white blood cell (WBC), neutrophil (NEU), hemoglobin (HGB), and hematocrit (HCT) levels were significantly lower in late-laying geese. Serum levels of luteinizing hormone (LH), estrogen (E2), and progesterone (P4) increased significantly during the late-laying period, whereas prolactin (PRL) level was lower in the late-laying period than the nesting period. During the late-laying period, geese had a clear follicular hierarchy, with ovaries exhibiting mature and primary follicles. In the nesting period, the ovaries were degenerated and had many primary follicles without follicular development. Analysis of mRNA-lncRNA expression revealed 1,257 DEGs between the nesting and the late-laying stages, of which 841 were up-regulated and 416 were down-regulated DEGs. A total of 340 DE lncRNAs were identified between the nesting and the late-laying periods, with 113 being up-regulated and 227 down-regulated lncRNAs. DEGs, including TMEM, DRD3, IGFBP7, MAPK13, GnRHR2, HECTD3, KCNU1, OPRD1, and VCAM1, along with DE lncRNAs, including XR_001203613.1, XR_001206155.1, XR_001207759.1, XR_001213571.1 and XR_001214368.1 participate in reproduction in geese. Correlation analysis indicated that the cis-regulation of XR_001213096.1-ITPR3, XR_001203613.1-GALNT15, XR_001206155.1-COL6A3, XR_001207759.1-ANKS1B, and XR_001214368.1-VPS45 participate in the molecular mechanisms underlying nesting in geese. Functional enrichment analysis revealed the DEGs and DE lncRNAs associated with focal adhesion, extracellular matrix (ECM)-receptor interaction, cell adhesion molecules (CAMs), and PI3K-Akt signaling pathways, were responsible for the differences in the ovaries between the nesting and late-laying periods. This study offers valuable information on the roles of genes and lncRNAs, and the mechanisms underlying variations in reproductive performance between the late-laying and nesting periods.

Transcriptomic Analysis Provides New Insights into Oocyte Growth and Maturation in Greater Amberjack (Seriola dumerili)

The greater amberjack (Seriola dumerili) is an emerging marine fish that is increasingly favored in aquaculture. Currently, there are few studies on the development and regulation of greater amberjack ovaries. In this study, the ovary transcriptome profiles of greater amberjack at three different stages (stage II, III, and IV) were performed, and identified the genes and pathways that may play significant roles in the processes of follicle growth and maturation. A total of 6597, and 1061 differentially expressed genes (DEGs) were detected in FII vs. FIII, FIII vs. FIV, and FII vs. FIV stages, respectively. GO and KEGG enrichment analyses revealed that these DEGS are primarily involved in steroid hormone biosynthesis (e.g., cyp11a1, cyp17a1, cyp19a1a, hsd3b1, esr1), lipid metabolism (e.g., plpp3, lpl, pld1, and fabp10a), and meiotic arrest and resumption (e.g., pgr, arb, ccnd2, adcy2, adcy9, myl9, calm1). Additionally, several signaling pathways involved in ovarian development have been identified, including the PI3K-Akt, Wnt, TGF-beta, GnRH, and immune-related signaling pathways. qPCR results of nine representative genes related to steroid hormone synthesis and cell growth verified the reliability of the generated RNA-seq data. This research contributes to our comprehension of the molecular processes underlying ovarian growth and maturation in marine fishes and provides a theoretical basis for the investigation of functional genes associated with oogenesis in greater amberjack.

Exploring the Mechanism of Acupuncture in Improving Ovarian Function in Rats with Poor Ovarian Response Using High-Throughput Sequencing.

This study aimed to investigate the possible mechanism through which acupuncture protects ovaries with Poor Ovarian Response (POR) in rats based on microRNA (miRNA). Thirty-six SPF SD female non-pregnant rats aged 8 weeks were randomly divided into the blank group, model group, and acupuncture group, with 12 rats in each group. According to the group, the rats were given gavage of Tripterygium wilfordii polyglycosides suspension for 14 days to establish the model of POR, and then the rats were treated with acupuncture for 2 weeks, once a day, for 20 minutes. Afterward, their hormone levels were measured, and HE staining was performed on the ovaries after the intervention. Three rats from each group were randomly selected for ovarian tissue miRNA sequencing, and differential miRNAs were subjected to Gene Ontology (GO) enrichment analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway analysis, and Quantitative Polymerase Chain Reaction (QPCR) verification. By using TargetScan to predict the target genes of differential miRNAs, we validated the results with a dual luciferase reporter gene assay. Compared with the blank group, the estrus cycle of the model group was significantly prolonged (P<0.01). Anti-Müllerian Hormone (AMH) (P<0.01) and Estrogen (E2) were significantly decreased (P<0.05). Follicle-Stimulating Hormone (FSH)(P<0.05) and Luteinizing Hormone (LH) increased sharply (P<0.01). Compared with the model group, the estrus cycle was significantly shortened in the acupuncture group (P<0.01). AMH and E2 were markedly raised (P<0.05). FSH (P<0.05) and LH (P<0.01) were significantly declined. miRNA sequencing showed that there were 23 miRNAs significantly different between the model group and the blank group (P<0.05), and 30 miRNAs significantly different between the acupuncture group and the model group (P<0.05). GO demonstrated that the network was mainly involved in cellular components, cells, cellular metabolic processes, binding, and single biological processes; KEGG signaling pathway enrichment showed that it was mainly related to MAPK, adhesion junction, calcium signaling pathways, etc. Q-PCR results showed that after modeling, the expression rose, and after acupuncture, the expression of the following miRNA decreased: miR-154-5p (P<0.01), miR-300-5p (P < 0.05), miR-376c-5p (P<0.05). The dual luciferase reporter assay showed that the relative luciferase activity of the miR-300-5p mimics+MAP3K1-WT group was significantly lower than that of the NC+MAP3K1-WT group (P<0.01). HE results demonstrated that the number of primordial follicles and primary follicles in the model group was significantly lower than that in the blank group (P<0.05). Moreover, the morphology was poorer, and the granulosa cell layer was thinner. Compared with the model group, the number of primary follicles in the acupuncture group increased (P<0.05); the morphology and granulosa cell structure of the ovary were improved to different degrees, and mature follicles could be seen. Acupuncture may improve the ovarian responsiveness of POR rats by regulating miR-154- 5p,miR-300-5p, and miR-376c-5p. Furthermore, miR-300-5p can specifically bind to the 3'-UTR of MAP3K1, and MAP3K1 may be the target of miR-300-5p.

Defective Mammary Epithelial Outgrowth in Transgenic EKAREV–NLS Mice: Correction via Estrogen Supplementation and Genetic Background Modification

Fluorescent biosensors offer a powerful tool for tracking and quantifying protein activity in living systems with high temporospatial resolution. However, the expression of genetically encoded fluorescent proteins can interfere with endogenous signaling pathways, potentially leading to developmental and physiological abnormalities. The EKAREV-NLS mouse model, which carries a FRET-based biosensor for monitoring extracellular signal-regulated kinase (ERK) activity, has been widely utilized both in vivo and in vitro across various cell types and organs. In this study, we report a significant defect in mammary epithelial development in EKAREV-NLS C57BL/6J female mice. Our findings reveal that these mice exhibit severely impaired mammary epithelial outgrowth, linked to systemic defects including disrupted estrous cycling, impaired ovarian follicle maturation, anovulation, and reduced reproductive fitness. Notably, estrogen supplementation was sufficient to enhance mammary epithelial growth in the EKAREV-NLS C57BL/6J females. Furthermore, outcrossing to the ICR genetic background fully restored normal mammary epithelial outgrowth, indicating that the observed phenotype is dependent on genetic background. We also confirmed the functional performance of the biosensor in hormone-supplemented and outcrossed tissues through time-lapse imaging of primary mammary epithelial cells. Our results underscore the critical need for thorough characterization of biosensor-carrying models before their application in specific research contexts. Additionally, this work highlights the influence of hormonal and genetic factors on mammary gland development and emphasizes the importance of careful consideration when selecting biosensor strains for mammary studies.

PH-responsive hydrogel with dual-crosslinked network of polyvinyl alcohol/boric acid for controlled release of salvianolic acid B: novel pro-regenerative mechanisms in scar inhibition and wound healing.

This study investigates a novel pH-responsive hydrogel composed of polyvinyl alcohol (PVA) and boric acid (BA) designed for the controlled release of salvianolic acid B (SAB), addressing the critical challenge of scar formation and skin regeneration. The dual-crosslinked network architecture of the hydrogel exhibits remarkable pH sensitivity, enabling it to achieve a peak SAB release within 48 hours in the acidic microenvironment characteristic of early-stage wound healing. In vitro assessments demonstrated that the PVA-BA-SAB hydrogel significantly inhibits fibroblast activation and mitigates abnormal collagen deposition, effectively preventing excessive scar formation. Transcriptome sequencing reveals the potential role of PVA-BA-SAB hydrogel in balancing TGF-β and Wnt signaling pathways. Furthermore, in vivo studies revealed enhanced tissue regeneration, characterized by improved collagen organization and increased vascularization, as well as the promotion of mature hair follicle development. The hydrogel's biocompatibility, mechanical robustness and adhesive properties were also thoroughly evaluated, confirming its suitability for clinical applications. These findings suggest that the PVA-BA-SAB hydrogel fully exerts the excellent characteristics of biomaterials and maximizes the pharmacological effect of SAB. Our innovative drug delivery system not only facilitates enhanced wound healing but also offers a strategic approach to minimize scarring. This research provides valuable insights into innovative therapeutic strategies for effective wound management and tissue repair.

Fetal fibroblast heterogeneity defines dermal architecture during human embryonic skin development.

To investigate heterogeneity of fibroblasts in human fetal skin, we analysed published single-cell RNA sequencing data (8 and 16 post conception weeks (PCW)) and performed single-molecule fluorescence in situ hybridisation to map their spatial distribution and predicted dynamic interactions. Clustering revealed 8 fibroblast populations with developmental stage-specific abundance changes. Proliferative cells (MKI67+) were present at all stages. The appearance of dermal papilla (PRDM1+) and hair follicle (SLC26A7+) fibroblasts coincided with hair follicle maturation, while fibroblasts (APOE+) specifically associated with blood vessels increased in abundance as the vessels developed. HOXC5 was a marker of the most abundant 7-8 PCW fibroblasts; this cluster was diminished at 9-13 PCW and undetectable subsequently. A second population (PLAT+) decreased in abundance with the same kinetics. Fibroblasts corresponding to papillary dermis (GRP+) were predominant at 9-13 PCW while reticular dermal fibroblasts (ASPN+) were the major cluster at 14-16 PCW. Partition-based graph abstraction and pseudotime analysis indicated that the HOXC5+ fibroblasts is closely connected with the papillary and hair follicle fibroblasts, while the PLAT+ fibroblasts is connected with reticular and vascular fibroblasts. Dermal papilla fibroblasts are the most highly differentiated. Integration of fetal and adult datasets distinguish the adult and fetal papillary clusters from the reticular clusters.

Productive, Reproductive, Behavioural, Gene Expression, Histological, and Economic Criteria of Feeding Fenugreek and Berseem Seeds as Alternative Protein Sources in New Zealand White Does Rabbits (Oryctolagus Cuniculus).

Feed cost represents about 70% of the total production costs of rabbit farms. There is little research on the usage of Berseem and Fenugreek seeds as substitutes for soybeans in rabbit diets. The current investigation was conducted to assess the influence of dietary inclusion of Fenugreek and/or Berseem seeds at varying levels as a substitute for soybean meal on reproductive performance, milk production, maternal behaviour, economic efficiency, mammary gland and ovarian histology, and relative expression of reproductive genes of New Zealand White rabbit does. Eighty fully grown New Zealand White does weighing between 2.75 and 3.00 kg live weight and aged 5-6 months old were utilized. Rabbits were allocated into four groups (20 rabbits/group): control group (basal diet), T1 (5% fenugreek), T2 (15% Berseem seeds), and T3 (2.5% Fenugreek with 7.5% Berseem seeds). We noticed that the dietary inclusion of Fenugreek and/or Berseem seeds significantly improved weight and total weight gain of litters. The increased body weight and decreased feed costs were accompanied by improved return parameters, including total return, net return economic efficiency, and relative economic efficiency, particularly in the T2 and T3 groups. Moreover, milk yield was increased in treated groups compared with those fed basal diet. The improved milk yield was associated with the enhancement of mRNA expression of the prolactin gene and improved mammary morphological characteristics, especially in the T1 group. Indeed, a rabbit does in T2 group revealed an earlier nest building, a higher nest quality, and an increased willingness to nurse. While those in T1 group presented the highest percentages of kits with full bellies. Interestingly, T2 and T3 had large mature follicles (preovulatory follicles) and few numbers of small follicles which was associated with a marked upregulation of mRNA levels of follicular stimulating hormone gene. It would be concluded that the dietary inclusion of Berseem seeds as a complete or partial replacement for soybean in New Zealand white rabbits' diet could be used to enhance the growth performance of litter and improve doe's milk production, maternal behaviour, and economic efficiency.

Polycystic Ovary Syndrome and Eating Disorders-A Literature Review.

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder that affects women of reproductive age and is characterized by hyperandrogenism, ovulatory dysfunction and polycystic ovarian morphology. PCOS is often associated with hormonal imbalances, metabolic dysfunction and comorbid psychiatric disorders, including eating disorders (EDs). The review identifies key hormonal factors-serotonin, leptin, insulin, ghrelin, kisspeptin and cortisol-and their roles in the pathophysiology of PCOS and associated psychiatric symptoms. Serotonin deficiency, commonly seen in PCOS patients, is associated with mood and eating disorders. Fluctuations in leptin, the satiety hormone, affect hypothalamic-pituitary-ovarian axis function and ovarian follicle maturation, increasing the risk of infertility. Elevated levels of kisspeptin in PCOS patients contribute not only to hormonal dysregulation but also to increased susceptibility to eating disorders such as bulimia and binge eating, likely due to its influence on the limbic system and glucose metabolism. Hyperinsulinemia and insulin resistance further impair reproductive and metabolic health, while promoting eating disorders such as binge eating and bulimia. Ghrelin and cortisol also emerge as significant factors. The review emphasizes the bidirectional relationship between PCOS and eating disorders, in which hormonal imbalances perpetuate psychiatric conditions, creating a vicious cycle. A multidisciplinary approach including gynecologists, endocrinologists, psychiatrists and nutritionists is recommended to ensure complex treatment. Early identification of those at risk through targeted screening and personalized interventions is key. Future research should focus on discovering the underlying hormonal mechanisms to improve treatment strategies and quality of life for women with PCOS.

Fertility potential in patients with ovarian cancer

Malignant neoplasms of the reproductive system are the most common form of oncological morbidity in women, accounting for over 30% of all cancer cases. Most antineoplastic agents act by inducing DNA damage in highly proliferating cancer cells, resulting in oocyte death. Ovarian toxicity is the most common side effect of cancer treatment in young women. Both chemotherapy and radiotherapy have been shown to be toxic to the ovaries, increasing the risk of premature ovarian failure, early menopause, endocrine disorders, and infertility. Patients who have undergone cancer treatment have severe follicular atresia, even if they have a regular menstrual cycle. Currently, the most effective methods of preserving fertility in cancer patients include cryopreservation of oocytes and embryos after ovarian hyperstimulation. Other fertility preservation methods include ovarian tissue cryopreservation, follicle or embryo maturation in vitro, ovarian transposition, ovarian suppression, and adjuvant therapy. Despite promising fertility prospects, iatrogenic infertility is one of the most undesirable adverse effects of cancer therapy for young women. Timely referral to a gynecologist prior to chemotherapy or radiation therapy is key to successful fertility preservation. Women should be aware of the available opportunities of assisted reproductive technologies, along with potential risks and failures with regard to their age, stage of disease, and treatment method. At this stage, it is necessary to develop well-defined and effective algorithms for oncologists, obstetrician-gynecologists, fertility specialists, and embryologists.

Ultrasound-based geometric modeling of the human ovary with applications to cryopreservation.

Successful cryopreservation of the whole ovary outside of the body, while a woman undergoes cancer treatments, may help preserving fertility and regaining hormone balance during recovery. One of the key challenges in whole ovary cryopreservation is adequately loading the organ with cryoprotective agents (CPAs). Another notable challenge in developing the application is the lack of geometric data needed for designing matching thermal protocols. The objective of the current study is twofold: (i) to develop an effective geometric reconstruction method for the ovary, based on transvaginal ultrasound (TVUS) data, and (ii) to perform a pilot study on the thermal effects associated with CPA loading with application to vitrification. This study includes screening of 127 TVUS imaging datasets of ovaries from healthy ovulatory participants, reconstruction of 14 geometric models, and thermally analyzing two representative geometric models of low and high mature follicles-to-organ volume ratios. Results of this study demonstrate that the proposed reconstruction method is faster and more accurate than that facilitated by commercially available software (SonoAVC, GE Healthcare). Two extremes were investigated: (1) complete vitrification of the ovary, and (2) crystallization of mature follicles while the remaining ovarian stroma vitrifies. CPA loading into the mature follicles is considered an outstanding cryopreservation challenge, but with very little impact on long-term fertility preservation. Results of this study suggest that ovarian preservation by vitrification is feasible when sufficient CPA loading is achieved, while identifying the most suitable CPA for the task remains a challenge beyond the scope of the current study.

A Review of Mathematical Modelling Methods for Bovine Hormone Dynamics.

This paper explores various approaches to modeling the bovine estrus cycle, focusing on improving estrus detection to enhance reproductive management in dairy cattle. The review examines a range of mathematical models, including hormonal models based on ordinary differential equations (ODEs) that simulate hormone dynamics, as well as follicular competition models that track the maturation of individual follicles. In addition to these, Precision Dairy Monitoring Technologies (PDMT) are discussed, which utilize real-time physiological and behavioral data to provide predictive insights into estrus. The paper assesses the effectiveness of both traditional modeling approaches and PDMT in improving breeding efficiency, minimizing labor, and optimising herd management practices.

146 Relationship between preovulatory follicle maturity and the follicular fluid metabolome

146 Relationship between preovulatory follicle maturity and the follicular fluid metabolome

Steroid metabolism and hormonal dynamics in normal and malignant ovaries.

The ovaries are key steroid hormone production sites in post-pubertal females. However, current research on steroidogenic enzymes, endogenous hormone concentrations and their effects on healthy ovarian function and malignant development is limited. Here, we discuss the importance of steroid enzymes in normal and malignant ovaries, alongside hormone concentrations, receptor expression and action. Key enzymes include STS, 3β-HSD2, HSD17B1, ARK1C3, and aromatase, which influence ovarian steroidal action. Both androgen and oestrogen action, via their facilitating enzyme, drives ovarian follicle activation, development and maturation in healthy ovarian tissue. In ovarian cancer, some data suggest STS and oestrogen receptor α may be linked to aggressive forms, while various oestrogen-responsive factors may be involved in ovarian cancer metastasis. In contrast, androgen receptor expression and action vary across ovarian cancer subtypes. For future studies investigating steroidogenesis and steroidal activity in ovarian cancer, it is necessary to differentiate between disease subtypes for a comprehensive understanding.

To examine the potential effectiveness of &lt;i&gt;Psidium guajava&lt;/i&gt; in Letrozole induced polycystic ovarian syndrome in female albino rats

Polycystic ovarian syndrome (PCOS) is a common endocrine disorder characterized by hormonal imbalances, metabolic disturbances, and ovarian dysfunction. This study aimed to investigate the therapeutic potential of methanol extract from Psidium guajava leaves as a natural remedy for alleviating PCOS symptoms in female albino rats. The experimental approach involved assessing critical physiological and biochemical markers both before and after treatment, including body weight, blood levels of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH), ovarian weight, and the FSH/LH ratio. Anti-inflammatory effects were evaluated by measuring inflammatory markers like TNF-α and lipid-derived mediators. Furthermore, a histological analysis of ovarian tissue was performed to observe changes in follicular development and ovarian structure. The results showed that Psidium guajava treatment significantly improved hormonal profiles, reduced inflammation markers, and promoted the regeneration and maturation of ovarian follicles, counteracting hyperandrogenism and inflammation associated with PCOS. These findings suggest that Psidium guajava leaf extract could be a promising adjunct therapy for managing PCOS, supporting endocrine balance, ovarian health, and inflammation reduction. However, further studies are needed to understand the underlying mechanisms and long-term effects of this botanical treatment.

Transcriptomic Response of the Ovarian Follicle Complex in Post-Vitellogenic Rainbow Trout to 17α,20β-Dihdroxy-4-pregnen-3-one In Vitro.

Gonadotropins and progestins are the primary regulators of follicle maturation and ovulation in fish, and they require complex communication among the oocyte and somatic cells of the follicle. The major progestin and the maturation-inducing hormone in salmonids is 17α,20β-dihdroxy-4-pregnen-3-one (17,20βP), and traditional nuclear receptors and membrane steroid receptors for the progestin have been identified within the follicle. Herein, RNA-seq was used to conduct a comprehensive survey of changes in gene expression throughout the intact follicle in response to in vitro treatment with these hormones to provide a foundation for understanding the coordination of their actions in regulating follicle maturation and preparation for ovulation. A total of 5292 differentially expressed genes were identified from our transcriptome sequencing datasets comparing four treatments: fresh tissue; untreated control; 17,20βP-treated; and salmon pituitary homogenate-treated follicles. Extensive overlap in affected genes suggests many gonadotropin actions leading to the acquisition of maturational and ovulatory competence are mediated in part by gonadotropin induction of 17,20βP synthesis. KEGG analysis identified signaling pathways, including MAPK, TGFβ, FoxO, and Wnt signaling pathways, among the most significantly enriched pathways altered by 17,20βP treatment, suggesting pervasive influences of 17,20βP on actions of other endocrine and paracrine factors in the follicle complex.

Exploring the distribution of polymorphism across diverse breeds Worldwide in the bovine NR5A2 gene and its correlation with number of mature follicles and corpus albicans

The Nuclear receptor subfamily 5 group A member 2 (NR5A2) gene plays a pivotal role in ovarian development, ovulation, and reproductive traits. There is a lack of studies on its impact on ovarian traits and reproductive traits in cattle. This study aimed to explore NR5A2 gene polymorphisms associations with reproductive traits and investigate the distribution of NR5A2 gene polymorphisms across diverse bovine breeds worldwide. We identified a novel 17-bp deletion within the NR5A2 gene specifically in Chinese Holstein cows (n = 1033) leading to the observation of two genotypes DD and ID. Subsequent association analysis revealed a significant correlation between the ‘ID’ genotype at this locus and a larger number of corpus albicans (p = 0.042) in diestrus, as well as a higher number of mature follicles (p = 0.038) in estrus. In addition, we also found that the distribution of this deletion exhibits strong regionality across different cattle breeds globally. These findings indicate that the 17-bp deletion mutation within the NR5A2 gene is significantly associated with an increased corpus luteum diameter and a greater number of mature follicles, suggesting its potential utility as a valuable DNA marker for enhancing cow fertility.

Successful Live Birth Outcome in A Patient with Empty Follicle Syndrome: A Case Report and Literature Review.

Here, we report on a rare case of a successful live birth in a patient with empty follicle syndrome. A 35-year-old woman with ovulatory disorder and a 4-year history of primary infertility conducted in vitro fertilization-embryo transfer (IVF-ET) treatment in our hospital. The patient experienced six controlled ovarian stimulation cycles. In the first two cycles, despite adequate ovarian response, normal development of multiple follicles, and normal serum estradiol (E2) levels, no oocytes were retrieved from these mature follicles during the aspiration procedure. The patient was diagnosed with "empty follicle syndrome". Whole exome sequencing (WES) identified a missense mutation in the luteinizing hormone/chorionic gonadotropin receptor (LHCGR). In subsequent cycles, we try to increase the trigger dosage, combine gonadotropin-releasing hormone agonists (GnRH agonist) with human chorionic gonadotropin (HCG) for a dual trigger, supplement with luteinizing hormone (LH)-like active substances during the stimulation process, and extend the time between triggering and oocyte retrieval. In the end, successful oocyte retrieval and pregnancy were achieved.

Transcriptomic data reveals MYC as an upstream regulator in laying hen follicular recruitment

Understanding the mechanisms of follicular recruitment is essential for improving laying hen and broiler breeder productivity, as it directly influences egg production. Despite advancements in poultry breeding for enhanced egg production, the factors driving successful ovarian follicle maturation remain inadequately understood. This study investigates the genetic drivers mediating the transition of pre-recruitment follicles to the pre-ovulatory phase, a crucial stage before ovulation. Using RNA sequencing and bioinformatics approaches such as a differential gene expression analysis, we compared pre-recruitment follicles with the recently recruited F5 pre-ovulatory follicle to identify key genes and upstream regulators involved in this transition. Further validation through qRT-PCR confirmed these findings. Using Qiagen's Ingenuity Pathway Analysis we identified MYC proto-oncogene (C-Myc) as a pivotal upstream regulator, controlling genes essential for cell proliferation and differentiation. Additionally, TGFβ1 emerged as a key regulator, influencing pathways involving SMAD3, TNF, and TP53. The study highlights the intricate regulatory network involving MYC and other transcription factors such as CTNNB1, crucial for follicular development. These findings provide valuable insights into the molecular mechanisms governing follicular selection and maturation, which are essential for enhancing egg production efficiency. Future research should explore the roles of MYC, CTNNB1, and other driver genes in follicular development to further understand and improve reproductive efficiency in poultry.

Dynamic maternal synthesis and segregation of the germ plasm organizer, Bucky ball, in chicken oocytes and follicles

Maternal germ plasm determines the germline in birds. Previously, we proposed the chicken-specific Bucky ball (cBuc) as a functional equivalent of the zebrafish germ plasm organizer. This study demonstrated the maternal cBuc synthesis, and verified a highly dynamic distribution of Bucky ball from oocyte nests to maturing follicles using specific antibodies. The dynamic re-localization of cBuc from the ovarian stroma to the granulosa cells, and the Balbiani structure of the oocyte was revealed. Following the accumulation of cBuc in the Balbiani body, an increased signal of chicken vasa homolog (CVH) in close contact to cBuc could be detected. Highest transcription of cBuc was recorded in follicles with diameters up to 500 µm. First RNA-interference experiments in an in-vivo follicle culture assay revealed inhibiting effects on cBuc in small follicles. These data demonstrate the maternal origin of cBuc, and underpin its role as germ plasm organizer.