[This retracts the article DOI: 10.1016/j.omtn.2021.03.004.].

Skeletal muscle development, orchestrated by muscle stem cells (MuSCs), is a critical determinant of meat yield and quality in cattle. Transcription factors (TFs) are pivotal regulators of MuSCs fate, yet their specific roles in meat quality remain largely unexplored. In this study, we integrated ATAC-seq and RNA-seq analyses to delineate the chromatin accessibility landscape and transcriptomic dynamics during bovine MuSCs myogenesis, identifying ZBTB18 as a core TF dynamically regulated in this process. ZBTB18 expression was higher in muscles enriched with oxidative myofibers and positively correlated with beef eating quality-related parameters. Functional assays demonstrated that ZBTB18 inhibits MuSCs proliferation while promoting myogenic differentiation, with a specific bias toward oxidative myofiber formation. Mechanistically, we established that ZBTB18 acts as a transcriptional repressor of STAT1. Our findings unveil ZBTB18 as a novel regulator of bovine myogenesis via transcriptional repression of STAT1. Notably, ZBTB18 expression is significantly associated with oxidative myofiber formation and beef eating quality. These findings also provide a strategic target for precision breeding to enhance meat quality in cattle.

The river buffalo is an economically important livestock species supplying milk and meat. However, a multi-tissue transcriptomic atlas for the key dairy river buffalo breeds, Murrah and Nili-Ravi, has not yet been established, and the lack of stable reference genes has hindered in-depth studies of their biological functions and the molecular mechanisms underlying key economic traits such as lactation. We established a multi-tissue gene expression atlas across 20 tissues and identified 717 housekeeping genes (HKGs), and RPL37A and EEF2 were further shown to be stable candidate reference genes under the conditions tested. We found 8368 tissue-specific genes (TSGs), predominantly enriched in the reproductive system. Exploratory analysis of mammary tissue (dry-period vs. public lactating samples, confounded by batch effects) revealed mammary-enriched hub genes including LALBA; these findings are preliminary and require validation. Dynamic analysis across lactation stages (early, peak, mid-, late) identified candidate genes including SEC14L2 and ACSM3. Phenotypic data showed strong negative correlations between milk yield and protein/fat content, and a positive correlation with lactose content. However, causal or regulatory roles were not inferred due to lack of paired individual-level data. Cross-dataset comparisons are descriptive only, and are not key conclusions. In summary, this study lays the foundation for advancing research in lactation trait genetics and functional genomics in river buffalo, with novel reference genes and lactation stage-specific transcriptional dynamics as its main contributions.

Research on in vitro gametogenesis (IVG) provides novel approaches to the investigation of germ cell development mechanisms and the conservation of elite livestock germplasm resources. Rabbits are an ideal animal model and highly suitable for preliminary studies. However, it is widely acknowledged that pluripotent state of rabbit embryonic stem cells (rbESCs) is primed, which limits their differentiation potential. Given the important role of the Wnt signaling pathway in regulating the pluripotency of ESCs, this study investigated how modulating this pathway affects both the pluripotency state and differentiation potential of rbESCs. The results indicate that regulating the Wnt signaling pathway is sufficient to reshape the pluripotency state of rbESCs and significantly enhance their proliferative capacity. Furthermore, upon induction of differentiation toward primordial germ cells (PGCs), it was found that rbESCs exhibited a propensity to differentiate into rabbit primordial germ-like cells (rbPGCLCs). Moreover, under the action of the Wnt signaling pathway, the resulting rbPGCLCs were more similar to in vivo PGCs. Consistently, transcriptome analysis revealed that the Wnt signaling pathway not only regulates the pluripotency of rbESCs but also enhances their ability to differentiate into PGCs. In conclusion, our results demonstrate that modulating the Wnt signaling pathway can enhance the pluripotency and germline specification ability of rbESCs.

Apoptosis of mammalian granulosa cells (GCs) is considered to be the main cause of follicular atresia. MiRNA-mediated post-transcriptional gene regulation plays a pivotal role in cell apoptosis. Our previous studies demonstrated that miR-424 is highly expressed in atretic follicles and may promoter of buffalo follicular atresia. In this study, we investigated the role and molecular mechanisms of miR-424 in buffalo follicular atresia. GCs apoptosis, proliferation and estrogen secretion were assessed by flow cytometry, EdU and ELISA, respectively. The expression levels of relevant genes were measured by qRT-PCR. Last, miR-424 agomir and antagomir was administered to mice via tail vein injection. The results showed that miR-424 promotes follicular atresia by inducing cell cycle arrest, inhibiting GC proliferation, suppressing the secretion of estradiol, and enhancing apoptosis. SERPINB2, as a target gene of miR-424, inhibits follicular atresia by promoting GCs proliferation, hormone secretion and inhibiting GCs apoptosis. Overexpression of miR-424 or silencing of SERPINB2 significantly reduced the number of follicles at various developmental stages in mice, whereas inhibition of miR-424 yielded opposite effects. In conclusion, our findings establish miR-424 as a key regulator of follicular atresia in buffalo, through direct targeting of SERPINB2 to modulate granulosa cell functions.

Due to the limited in vitro culture duration, oocyte maturation efficiency in vitro is lower than in vivo. Nicotinamide mononucleotide (NMN), a precursor of NAD+ and a cofactor of Sirtuin deacetylases, exhibits significant antioxidant activity. This study aims to evaluate whether NMN supplementation combined with prolonging maturation time enhances cytoplasmic maturation and improves porcine oocyte quality. The blastocyst rate increased significantly after parthenogenetic activation when maturation time was extended from 44 h to 47 h or 50 h, peaking at 47 h. Prolonged maturation improved mitochondrial function and cortical granule distribution but induced ROS accumulation and apoptosis. Notably, supplementation with 100 μM NMN reversed these negative effects, significantly increasing the total number of blastocyst cells, reducing ROS levels, and upregulating cytoplasmic quality-related gene expression. In conclusion, extending maturation to 47 h with 100 μM NMN supplementation enhances oocyte maturation and embryonic developmental potential in vitro. These findings suggest that NMN, a naturally occurring nucleotide in food, may improve oocyte quality and offer insights for optimizing in vitro culture techniques as well as treating oocyte quality-related infertility.

Super-enhancers (SEs) are critical epigenetic regulators of tissue regeneration, yet their interplay with cellular biomechanics during myogenic differentiation remains unexplored. Here, the TPM1 locus, encoding a core actin-stabilizing protein essential for skeletal muscle regeneration, harbors an evolutionarily conserved SE (TPM1_SE) that may bridge epigenetic control and mechanotransduction. In vitro, TPM1_SE deletion impaired myogenic differentiation and diminished expression of both TPM1 and its circular RNA (circRNA) isoform, CircTPM1. Conditional deletion of TPM1_SE significantly reduce muscle mass and delayed regenerative progression. Mechanistically, TPM1_SE drives expression of linear TPM1 mRNA (mice) and CircTPM1 (bovine) via TEAD4-mediated chromatin looping, coordinating cytoskeletal reorganization during myotube formation. These effects are mediated via activation of the canonical PI3K/AKT signaling pathway through interaction with NKX2.2-a pathway mechanosensitive to cellular tension. Loss of TPM1_SE disrupted NKX2.2-PI3K/AKT signaling. Crucially, CircTPM1 directly bound MYH10, enhancing MYL3-dependent actomyosin assembly, which potentiates cytoskeletal reorganization during myotube formation. Collectively, this findings establish TPM1_SE as an evolutionarily conserved hub integrating epigenetic regulation and biomechanical output. While the murine model underscores its therapeutic potential in muscle regenerative medicine, the bovine CircTPM1-mediated mechanism highlights TPM1_SE as a promising target for genetic improvement of meat quality in livestock.

The specific expression profile and function of circular RNA (circRNA) in follicular atresia remain largely unknown. Here, the circRNA expression profiles of granulosa cells derived from healthy follicles (HFs) and antral follicles (AFs) in buffalo were analyzed by RNA-seq, and the mechanism of a differentially expressed circRNA (DEcircRNA) circTEC regulating the granulosa cell function that affects follicular atresia was further explored. RNA-seq results showed that a total of 112 DEcircRNAs were identified. Among them, circTEC was highly expressed in HF, and its circular structure was confirmed by RNase R digestion assay, reversed PCR and Sanger sequencing. Functional experiments demonstrated that circTEC promotes the proliferation and steroid hormone synthesis of buffalo granulosa cells (bGCs), and it also inhibits their apoptosis. In-depth mechanism analysis showed that the expression level of circTEC in bGCs from AFs was adversely related to miR-144-5p and consistent with FZD3. CircTEC acts as an endogenous sponge of miR-144-5p to regulate the expression of the target gene FZD3 in AFs, which promotes the proliferation of bGCs and inhibits bGCs apoptosis, thereby inhibiting follicular atresia in buffalo. In summary, our study revealed the regulatory role of the circTEC/miR-144-5p/FZD3 axis during follicular atresia in buffalo. These results provided new insights into the biological mechanism underlying follicular atresia.

Background/Objectives: As a well-known source of energy from feed, the significance of fatty acids in regulating the reproductive potential of livestock has received attention in recent years, especially follicular development. Moreover, successful ovulation is a process that is crucial for reproduction and fertility in domestic animals. Therefore, it is important to reveal the signatures of fatty acids in follicular fluid during mammalian ovulation, and this provides a possible method to prevent the occurrence of ovarian cysts in domestic animals. Methods: Pre-ovulatory follicles (n = 6) and peri-ovulatory follicles (n = 6) during normal ovulation, as well as cystic follicles (n = 6) in ovulation-deficient ovarian cyst were isolated and characterized, while follicular fluid was collected for targeted fatty acid metabolomics detection and analysis. Results: We have illustrated the anatomical and biochemical characterization of pre-ovulatory, peri-ovulatory, and cystic follicles. Subsequently, we identified changes in 51 fatty acids profiles in the follicular fluid. The highest proportion of fatty acids in the follicular fluid at three different ovulation stages is polyunsaturated fatty acids, among which the abnormality of the linoleic acid metabolism pathway was involved in ovulation defects in cystic follicles. Remarkably, we found that linoleic acid was significantly increased while arachidonic acid was significantly decreased in cystic follicles. Conclusions: Polyunsaturated fatty acids play a significant role in the follicular ovulation stage of sows. Among them, linoleic acid and arachidonic acid are closely related to the ovulation defects of cystic follicles, which suggests that identifying changes in important metabolic signatures may give us a better understanding of the pathogenesis of ovarian cyst.

Kynurenine (KYN) is a primary tryptophan derivative found in the human body and fermented foods. Previous studies have shown that KYN is an aryl hydrocarbon receptor (AHR) agonist and is important in regulating various physiological activities, including female reproduction. Progesterone is a vital steroid hormone that facilitates embryo implantation and maintains pregnancy. However, whether KYN affects its biosynthesis remains unclear. To gain understanding, in vitro luteinized porcine granulosa luteal (pGL) cells were treated with KYN. The results showed that KYN disrupted progesterone biosynthesis by decreasing the expression of steroidogenic acute regulatory protein (STAR) and 3beta-hydroxysteroid dehydrogenase (HSD3B) in pGL cells. In addition, the expression of three transcription factors of STAR and HSD3B (GATA4, GATA6, and CEBPB) decreased after KYN treatment. Furthermore, the AHR blockade results showed comparable effects to those of KYN treatment, and subsequent knockdown experiments confirmed these results. These findings suggest that KYN inhibits progesterone biosynthesis in pGL cells by downregulating GATA4, GATA6, and CEBPB expression through AHR. Thus, our results showed for the first time a previously unknown connection between KYN and progesterone biosynthesis.

The TGF-β/Smad signalling pathway plays a critical regulatory role in mammalian follicular development. Vascular Cell Adhesion Molecule 1 (VCAM1), as a member of the immunoglobulin (Ig) superfamily, is commonly expressed in various cells of the mammalian ovary and affects ovarian development. Previous studies have shown that TGF-β1 is a regulator that down-regulates the expression of VCAM1 in human granulosa cells, but its specific mechanism remains unclear. In this study, we revealed that in porcine follicular granulosa cells, TGF-β1 reduces VCAM1 expression by activating TGF-β receptor type I and through the Smad pathway. This down-regulation can be completely reversed by knockdown of Smad2, but not Smad3, suggesting that Smad2 may exert a non-redundant, specialised function in the regulation of VCAM1 by the TGF-β/Smad signalling pathway. These results enhance the understanding of the regulatory mechanisms of the TGF-β signalling pathway in reproduction and provide a theoretical basis for the regulation of reproductive traits.

Buffaloes are mono-ovulating animals, with only about 5% of primordial follicles being fully capable of maturation into primary oocytes throughout their reproductive years. In vitro primordial follicle activation technology provides a new way to manipulate and utilize oocyte resources. However, in vitro activation of buffalo primordial follicles has not been reported. In this study, buffalo cortical strips were cultured in vitro and activated with PI3K and mTOR stimulators, and the proportion of activated and developed follicles was evaluated and compared between groups . Furthermore, the key genes involved in primordial follicle activation were screened using RNA sequencing. Results showed that buffalo ovarian cortex can be well preserved by being cultured in vitro for at least 7 days and maintain its tissue properties and follicular morphology. In vitro, treatment with PI3K and mTOR pathway stimulators significantly enhanced the activation efficiency of the primordial follicles. In addition, several differentially expressed genes related to follicular development, such as IDO1, CXCL10 and CXCL6 were significantly up-regulated after stimulation. Our findings demonstrate that PI3K and mTOR stimulators can significantly promote the activation and development of buffalo follicles, and providing technical support and a theoretical basis for the optimization of in vitro culture technology of buffalo preantral follicles .

Serine protease inhibitor E2 (SerpinE2), a serine protease inhibitor predominantly expressed in ovarian granulosa cells (GCs), plays a critical role in follicular development and ovulation in mammals. However, its exact role and underlying mechanisms remain unclear. In this study, we used buffalo GCs as a research model to investigate both the effects of SerpinE2 on GCs function and the mechanisms governing its expression. RT-qPCR analysis revealed that SerpinE2 expression was significantly higher in healthy follicles (HFs) compared to atretic follicles (AFs). Through comprehensive functional assays (CCK-8, EDU, flow cytometry and ELISA), we demonstrated that SerpinE2 promotes GCs proliferation, enhances steroidogenesis (progesterone and estradiol), and suppresses apoptosis. Mechanistically, dual-luciferase reporter assays confirmed FOXL2 as a direct transcriptional activator of SerpinE2, with FOXL2 overexpression significantly enhancing both SerpinE2 expression and its steroidogenic effects. Additionally, Western blot analysis demonstrated that H3K9 methylation levels were significantly increased in AFs and FOXL2 knockdown GCs. CUT&RUN-qPCR further demonstrated that H3K9me3 was highly enriched in the promoter regions of SerpinE2 in AFs and FOXL2 knockdown GCs, leading to reduced SerpinE2 expression. These findings suggest that SerpinE2 promotes steroid hormone synthesis in GCs in a FOXL2-dependent manner; H3K9me3 is directly involved in FOXL2-mediated regulation of SerpinE2 transcription in GCs. This study provides new insights into the molecular mechanisms by which SerpinE2 regulates mammalian follicular development.

Abstract Kynurenine (KYN) is a primary tryptophan derivative found in the human body and fermented foods. Previous studies have shown that KYN is an Aryl hydrocarbon receptor (AHR) agonist and is important in regulating various physiological activities, including female reproduction. Progesterone is a vital steroid hormone that facilitates embryo implantation and maintains pregnancy. However, whether KYN affects its biosynthesis remains unclear. To gain understanding, in vitro luteinized porcine granulosa luteal (pGL) cells were treated with KYN. The results showed that KYN disrupted progesterone biosynthesis by decreasing the expression of STAR and HSD3B in pGL cells. In addition, the expression of three transcription factors of STAR and HSD3B (GATA4, GATA6, and CEBPB) decreased after KYN treatment. Furthermore, the AHR blockade results showed comparable to those of KYN treatment, and subsequent knockdown experiments confirmed these results. These findings suggest that KYN inhibits progesterone biosynthesis in pGL cells by downregulating GATA4, GATA6, and CEBPB expression through AHR. Thus, our results showed for the first time, a previously unknown connection between KYN and progesterone biosynthesis.

Skeletal muscle, the primary meat-producing tissue in bovines, is regulated by a complex transcriptional network during development. The role of Thrombospondin 3 (THBS3) and its associated super-enhancer (SE) in this process remains largely unknown. Here, by integrating multi-omics data, we identified THBS3 as a novel core regulator of myogenesis, orchestrated by a cognate super-enhancer (THBS3-SE). Functional assays demonstrated that THBS3 knockdown significantly promoted the proliferation and myogenic differentiation of bovine muscle stem cells (MuSCs) and accelerated their commitment to a fast-twitch fiber fate. Transcriptomic analysis linked THBS3 function to key signaling pathways controlling muscle growth, especially the mechanistic target of rapamycin (mTOR) signaling pathway. Mechanistically, we found that distal enhancers within the THBS3-SE loop to the THBS3 promoter drive its transcription, and CRISPR-based interference of these enhancers recapitulated the pro-myogenic effects of THBS3 knockdown. Collectively, our findings unveiled a THBS3-SE-mediated regulatory axis that critically governed bovine MuSCs’ fate. Targeting this axis may offer a novel strategy for improving beef production efficiency.

The spatiotemporal transcription of follicle-stimulating hormone receptor (FSHR) and luteinizing hormone/human chorionic gonadotropin receptor (LHCGR) are crucial events for follicular development. However, their regulatory mechanisms are unclear. DNA methylation and histone acetylation are the main epigenetic modifications, and play important roles in transcriptional expression, which regulate cell responses including cell proliferation, senescence and apoptosis. This review will discuss the dynamic epigenetic modifications of FSHR and LHCGR that occur during the process of follicular development and their response to gonadotropins. In addition, some alteration patterns that occur during these epigenetic modifications, as well as their retrospect retrotransposons, which regulate the gene expression levels of FSHR and LHCGR will be discussed.

本试验旨在研究2种不同蛋白水平日粮对湖羊生长性能、肉品质及血常规的影响.选择健康的5月龄公湖羊20只,随机分为2组,每组10只;对照组湖羊初始体重为(27.23±1.87)kg,基础日粮的粗蛋白水平为8.63％;高蛋白组湖羊初始体重为(27.21±1.79)kg,设计日粮的粗蛋白水平为16.35％;预试期7 d、正试期57 d.结果表明:高蛋白组湖羊试验结束时末重、平均日增重均显著高于对照组(P<0.05),料重比显著低于对照组(P<0.05);2组湖羊的净肉率、骨率和骨肉比差异不显著(P>0.05),高蛋白组湖羊的宰前活重、胴体重、屠宰率和净肉重均显著高于对照组(P<0.05);2组湖羊的肉品质相关指标无差异,其血常规指标均处于正常范围.由此可见,饲喂高蛋白水平日粮能显著提高育肥期湖羊生长性能,且不影响湖羊的健康和肉品质.

1 引言 高校肩负着立德树人、育才育人的时代重任,要解决好专业教育和思政教育"两张皮"的问题,课程思政应时代而产生,它将爱国主义教育、集体主义教育、生命教育、环保意识、安全教育、社会责任感等思政元素融入专业教育当中,将思想政治教育与专业教育有机的结合在一起,潜移默化地对学生的思想意识、行为举止产生影响,帮助学生塑造正确的世界观、人生观、价值观.

本实验旨在探讨甘氨脱氧胆酸(GDCA)对猪卵泡颗粒细胞状态和功能的影响,为后续研究GDCA对卵泡发育的影响提供一定的理论支持.利用猪卵泡颗粒细胞体外培养技术,在细胞对数生长期用不同浓度(0、50、100、200、400、800 μmol/L)的GDCA处理,分别采用CCK-8、流式细胞术、酶联免疫吸附实验(ELISA)和荧光定量PCR等方法,检测GDCA对体外培养猪卵泡颗粒细胞增殖、凋亡和类固醇激素合成的影响.结果表明:随着添加GDCA浓度增加,颗粒细胞的增殖率呈下降趋势,而凋亡率呈上升趋势,浓度达到 200 μmol/L时与对照组相比差异显著;不同浓度GDCA处理组的颗粒细胞培养基中类固醇激素:雌激素(E2)、孕酮(PROG)含量无显著变化;细胞增殖(CyclinD1和CDK4)、凋亡(CASPASE3、CASPASE8、CASPASE9和BAX)和激素合成相关基因(3βHSD和CYP19A1)的表达量与细胞表型相符.以上结果表明,GDCA可诱导猪卵泡颗粒细胞凋亡,抑制其增殖,但对猪卵泡颗粒细胞类固醇激素合成无显著影响.

本试验对水牛SERPINE2基因进行生物信息学分析,探索其在水牛不同组织器官中的表达规律,旨在为研究SERPINE2在水牛生殖过程中的具体调控机制提供理论支持.利用PCR技术克隆水牛SERPINE2基因CDS区的全长序列,在线生物信息学分析程序对SERPINE2进行分析,实时荧光定量PCR技术检测SERPINE2 mRNA在水牛不同组织的表达水平.结果表明:SERPINE2基因CDS区长度为1191 bp,编码397个氨基酸,通过分析相似性结果,发现水牛和牛、绵羊、山羊的相似性为99.6％;系统进化树结果显示,遗传距离最近的是水牛和牛,绵羊次之.在组成SERPINE2蛋白的氨基酸中,缬氨酸含量较高,占氨基酸总数的9.6％.SERPINE2蛋白是一种不稳定的亲水蛋白,SERPINE2有一个信号肽,没有跨膜结构域.SERPINE2蛋白的二级结构中,α-螺旋结构的占比最高,为41.56％.多个器官检测出SERPINE2 mRNA的表达,其中在卵巢的表达量显著高于其他器官,说明SERPINE2基因可能与卵巢生长发育有重大联系.