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.

HT-2 toxin, a common grain contaminant, has been shown to impair mammalian reproductive function, but its specific effects on the epigenetic modifications of oocytes have not been systematically elucidated. This study aimed to investigate the impact of HT-2 toxin exposure on epigenetic modifications in mouse oocytes and the potential intervention of melatonin. The results revealed that HT-2 exposure downregulated the expression of histone methyltransferases (Suv39h2, Ehmt1, Ezh1, Ezh2) and the DNA demethylase Tet3, leading to reduced levels of repressive histone modifications (H3K9me3, H3K27me3) and abnormally elevated DNA methylation, which in turn compromised oocyte quality and significantly reduced the blastocyst formation rate after fertilization. The addition of melatonin effectively reversed the dysregulation of these epigenetics-related genes, restored histone modification and DNA methylation levels, and significantly improved embryonic developmental potential. This study reveals a novel mechanism by which melatonin mitigates reproductive toxicity through multi-target correction of HT-2-induced epigenetic errors, providing a potential strategy for preventing and addressing reproductive health issues caused by environmental toxins.

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.

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.

Ovulation and granulosa cell luteinization are induced by ovulatory signals, including luteinizing hormone (LH) and human chorionic gonadotropin (hCG). Histone modifications enable rapid, signal-responsive transcriptional reprogramming. However, the effects of LH/hCG-induced histone modification changes on the mural granulosa cells (MGCs) function remain to be fully elucidated. By mining public datasets we integrated transcriptomic and histone-modification profiles of MGCs across the ovulatory interval and tracked LH/hCG-driven gene expression at three time points (0, 4, and 12 h after-hCG). During oocyte maturation, the 4 h LH-surge constitutes a critical window for meiotic resumption, during which many genes display rapid transcriptional changes followed by a return to baseline levels. Early-response genes are enriched for cell locomotion, inflammatory responses, the activation of signaling pathways, and histone modifications. Furthermore, LH/hCG-induced transcriptome remodeling is highly correlated with dynamic gains or losses of H3K4me3 and H3K27ac. Notably, we discovered for the first time that H3K27ac marks super-enhancers (SEs) that regulate LH/hCG-induced transcriptional activation in MGCs. Finally, through complementary in vitro and in vivo pharmacological inhibition, we demonstrate that LH/hCG governs oocyte maturation and ovulation by reshaping the MGC transcriptome via H3K4me3- and H3K27ac-dependent chromatin remodeling. In summary, our study advances the understanding of how gonadotropins regulate MGC function and oocyte maturation through histone-modification-mediated transcriptional control.

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.

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.

本试验旨在探讨日粮中不同水平蛋白质和能量对西门塔尔杂交牛生产性能和经济效益的影响,为生产高质量牛肉、增加养殖经济效益提供依据.试验选取体重、出生日期相近的健康西门塔尔杂交育肥牛(约220 kg)30头,随机分为对照组、试验Ⅰ组和试验Ⅱ组,每组各10头,分别饲喂含不同水平蛋白质和能量的日粮.结果表明:试验Ⅰ组在高能量、高蛋白的水平下净增重为1.93 kg/(头·d),净利润率可达19.5％,比对照组净利润率高13.1％;而试验Ⅱ组在蛋白含量一定、能量水平较高的条件下净增重为1.77 kg/(头·d),净利润率为16.4％,比对照组净利润率高10％.试验组日增重水平显著高于对照组(P<0.05).由此可见,适当地提高全混合颗粒日粮的养分含量,可以明显提升220～350 kg西门塔尔杂交育肥牛的增重效果,使得经济效益最大化.

广西贫困人口绝大部分分布在石漠化严重的大石山区,石漠化引起的生态恶化加剧了贫困程度,阻碍区域经济的发展.该研究探索广西石漠化山区肉牛养殖产业盈利运营模式,协调石漠化治理与肉牛产业发展之间的关系,加快实现脱贫攻坚奔小康和产业兴旺乡村振兴目标的步伐,提升人民群众生活水平和生活质量,为石漠化极度贫困山区肉牛产业持续发展壮大提供参考和借鉴.

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.

随着社会的发展和人民生活水平的提高,对肉类的需求逐步由传统的猪肉、鸡肉和鱼肉向牛肉等高档肉类消费转变.近年来,肉牛肉羊养殖产业市场行情稳中向好,大力的政策扶持使得大量的社会资本进入到牛羊养殖领域,各地牛羊草食动物养殖蓬勃发展,产业迅速扩大发展也逐渐暴露了制约产业发展的问题,牛羊养殖企业难赚钱、不赚钱、亏本经营的现象愈发普遍.本文调查和跟踪了桂林市牛羊产业发展状况,阐述了广西牛羊产业发展存在的共性问题,总结了养殖盈利运营的一些好的经验做法,为桂林以及广西牛羊产业高质量发展提供参考.

近年来,牛羊产业是广西农村巩固脱贫攻坚、助力乡村振兴的重要产业之一,是农业经济的重要组成部分.本文主要针对广西桂南地区牛羊养殖现状、产业发展区域优势、技术瓶颈、发展方向、解决方案及建议等发展态势进行分析,为助力乡村振兴、推动桂南地区牛羊产业经济带高质量发展提供参考依据.

The proliferation and myogenic differentiation of muscle stem cells (MuSCs) are important factors affecting muscle development and beef quality. There is increasing evidence that circRNAs can regulate myogenesis. We found a novel circRNA, named circRRAS2 that is significantly upregulated in the differentiation phase of bovine MuSCs. Here, we aimed to determine its roles in the proliferation and myogenic differentiation of these cells. The results showed that circRRAS2 was expressed in several bovine tissues. CircRRAS2 inhibited MuSCs proliferation and promoted myoblast differentiation. In addition, chromatin isolation by using RNA purification and mass spectrometry in differentiated muscle cells identified 52 RNA-binding proteins that could potentially bind to circRRAS2, in order to regulate their differentiation. The results suggest that circRRAS2 could be a specific regulator of myogenesis in bovine muscle.HighlightsCircRRAS2 expression is higher in DM cells than in GM cells.CircRRAS2 could significantly inhibit the proliferation and apoptosis of bovine MuSCs.CircRRAS2 promotes the differentiation of bovine MuSCs into myotubes.CircRRAS2 may exert regulatory effects through multiple RNA binding proteins.

As a gene with antiaging functions, sirtuin6 (SIRT6) belonging to the sirtuin family plays a vital role in DNA repair, telomerase function, and cellular senescence, as well as maintains epigenomic stability and promotes longevity. However, its role in cell senescence in large animals, such as buffaloes, remains unknown. Fibroblasts are commonly used for somatic reprogramming, and their physiological characteristics affect the efficiency of this process. We aimed to elucidate the role of SIRT6 in cellular senescence and proliferation and analyze its effect on the biological function of buffalo fibroblasts to help improve the efficiency of buffalo somatic cell reprogramming. The expression of SIRT6 and related DNA damage was measured in buffalo fibroblasts obtained at different developmental stages (in the fetus and at 3 and 10 years of age), and the effect of SIRT6 knockdown on the senescence of buffalo fetal fibroblast was investigated. An inverse relationship was observed between SIRT6 expression and senescence in buffalo fibroblasts obtained from animals of various ages. This was accompanied by decreased cell growth, viability, and increased DNA damage. Short hairpin RNA-mediated SIRT6 knockdown accelerated the senescence of buffalo fetal fibroblasts. It blocked the cell cycle during in vitro cell culture, which further enhanced DNA damage, particularly with respect to the telomeres. Collectively, our findings suggest that SIRT6 expression was closely associated with buffalo senescence in fibroblasts. These findings serve as a foundation to better understand the cellular functions of SIRT6 and also aid in selecting donor cells for buffalo somatic cell reprogramming.

【Objective】At present, studies have proved that circRNA plays important roles in the development of bovine muscle, but its molecular regulation mechanism remain elusive. Screening circRNAs related to bovine muscle development can lay a foundation for further elucidating the molecular mechanism of bovine muscle development.【Method】In this study, RNA-seq sequencing results of proliferating (GM) and myogenic differentiation (DM) yellow bovine muscle stem cells (MuSCs) analyzed in the previous stage were used to screen for significantly differentially expressed circRNA, circCEP85L. Tissue samples of heart, liver, spleen, lung, kidney, muscle, intestine and stomach were collected aseptically from fresh yellow fetal calves, and yellow muscle stem cells were isolated and cultured and induced into myogenic differentiation. GM and DM cells cultured in vitro from yellow calves were collected, RNA was extracted and reverse transcribed into cDNA, respectively. Quantitative real time PCR (qRT-PCR) was used to detect the expression of circCEP85L in different tissues and different cell states. Meanwhile, specific primers were designed to amplify the full length of circCEP85L, and the overexpression vector p-circCEP85L was constructed. The plasmid was transfected into MuSCs and overexpressed circCEP85L cell samples were collected. Using overexpression plasmid pCD5-ciR cell samples as control, qRT-PCR, flow cytometry, Western Blot and immunofluorescence were used to detect the effects of overexpression of circCEP85L on proliferation, apoptosis and myogenic differentiation of yellow bovine MuSCs.【Result】The electrophoresis of PCR product proved the existence of circCEP85L. CircCEP85L was expressed in various tissues, and the expression level in DM stage was significantly higher than that in GM stage (P<0.001). To further investigate the effect on circCEP85L scallion MuSCs. The overexpression vector p-circCEP85L was transfected with the control vector pCD5-ciR in vitro cultured yellow bovine MuSCs and the EdU results showed that overexpression of circCEP85L significantly reduced the proportion of EdU positive cells (P<0.001) after continuing the culture for 24 h. Flow cycle analysis showed that overexpression of circCEP85L increased the proportion of cells in G0/G1 phase and significantly decreased the proportion of cells in S phase (P<0.001). Flow cytometry showed that overexpression of circCEP85L significantly inhibited the apoptosis rate of MuSCs (P<0.05). qRT-PCR and western blot were used to detect the expression of proliferation and apoptosis-related genes in MuSCs, respectively. The results showed that overexpression of circCEP85L significantly reduced the mRNA expression levels of proliferation and apoptosis-related genes in bovine MuSCs (P<0.001), and the expression of apoptotic protein BAX was also significantly reduced (P<0.01). In addition, in order to detect the effect of circCEP85L overexpression on myogenic differentiation of cattle MuSCs, the differentiation medium was replaced 24 hours after transfection to induce cell differentiation. Western blot and immunofluorescence results showed that overexpression of circCEP85L significantly promoted the expression level of differentiation marker gene MyH6 (P<0.001), and the number and size of myotubes formed by cell fusion were significantly higher than those of the control group.【Conclusion】The results of this study indicate that circCEP85L affects the growth and development process of skeletal muscle in cattle by inhibiting the proliferation and apoptosis of MuSCs and promoting myogenic differentiation of cells, which is expected to be a key circRNA for subsequent mechanistic studies to regulate the growth and development process of skeletal muscle in cattle.

本试验旨在研究甘肃不同地区小麦秸秆纤维水平的差异.按不同地区分为5 组.采用范氏(Van Soest)法测定小麦秸秆中的NDF与ADF.结果表明,凉州、民乐、古浪三个县的NDF含量显著高于甘州和山丹两县(P<0.05),甘州高于山丹(P<0.05);古浪县小麦秸秆中的ADF含量显著高于凉州、民乐、甘州、山丹四个县的(P<0.05),凉州、民乐县的ADF含量又显著高于甘州、山丹这两县(P<0.05),同时甘州县小麦的ADF含量显著高于山丹县(P<0.05).这为今后不同地区小麦秸秆饲用采购提供一定的理论依据.