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Abstract Background DNA G-quadruplexes (G4s) represent a distinctive class of non-canonical DNA secondary structures. Despite their recognition as potential therapeutic targets in some cancers, the developmental role of G4 structures remains enigmatic. Mammalian embryonic myogenesis studies are hindered by limitations, prompting the use of chicken embryo-derived myoblasts as a model to explore G4 dynamics. This study aims to reveal the embryonic G4s landscape and elucidate the underlying mechanisms for candidate G4s that influence embryonic myogenesis. Results This investigation unveils a significant reduction in G4s abundance during myogenesis. G4s stabilizer pyridostatin impedes embryonic myogenesis, emphasizing the regulatory role of G4s in this process. G4 Cut&Tag sequencing and RNA-seq analyses identify potential G4s and DEGs influencing embryonic myogenesis. Integration of G4 and DEG candidates identifies 32 G4s located in promoter regions capable of modulating gene transcription. WGBS elucidates DNA methylation dynamics during embryonic myogenesis. Coordinating transcriptome data with DNA G4s and DNA methylation profiles constructs a G4-DMR-DEG network, revealing nine interaction pairs. Notably, the NFATC2 promoter region sequence is confirmed to form a G4 structure, reducing promoter mCpG content and upregulating NFATC2 transcriptional activity. Conclusions This comprehensive study unravels the first embryonic genomic G4s landscape, highlighting the regulatory role of NFATC2 G4 in orchestrating transcriptional activity through promoter DNA methylation during myogenesis.

Abstract Indicine cattle, also referred to as zebu (Bos taurus indicus), play a central role in pastoral communities across a wide range of agro-ecosystems, from extremely hot semiarid regions to hot humid tropical regions. However, their adaptive genetic changes following their dispersal into East Asia from the Indian subcontinent have remained poorly documented. Here, we characterize their global genetic diversity using high-quality whole-genome sequencing data from 354 indicine cattle of 57 breeds/populations, including major indicine phylogeographic groups worldwide. We reveal their probable migration into East Asia was along a coastal route rather than inland routes and we detected introgression from other bovine species. Genomic regions carrying morphology-, immune-, and heat-tolerance-related genes underwent divergent selection according to Asian agro-ecologies. We identify distinct sets of loci that contain promising candidate variants for adaptation to hot semi-arid and hot humid tropical ecosystems. Our results indicate that the rapid and successful adaptation of East Asian indicine cattle to hot humid environments was promoted by localized introgression from banteng and/or gaur. Our findings provide insights into the history and environmental adaptation of indicine cattle.

Haemophilus parasuis is a commensal organism of the upper respiratory tract of pigs, but virulent strains can cause Glässer’s disease, resulting in significant economic losses to the swine industry. OmpP2 is an outer membrane protein of this organism that shows considerable heterogeneity between virulent and non-virulent strains, with classification into genotypes I and II. It also acts as a dominant antigen and is involved in the inflammatory response. In this study, 32 monoclonal antibodies (mAbs) against recombinant OmpP2 (rOmpP2) of different genotypes were tested for reactivity to a panel of OmpP2 peptides. Nine linear B cell epitopes were screened, including five common genotype epitopes (Pt1a, Pt7/Pt7a, Pt9a, Pt17, and Pt19/Pt19a) and two groups of genotype-specific epitopes (Pt5 and Pt5-II, Pt11/Pt11a, and Pt11a-II). In addition, we used positive sera from mice and pigs to screen for five linear B-cell epitopes (Pt4, Pt14, Pt15, Pt21, and Pt22). After porcine alveolar macrophages (PAMs) were stimulated with overlapping OmpP2 peptides, we found that the epitope peptides Pt1 and Pt9, and the loop peptide Pt20 which was adjacent epitopes could all significantly upregulated the mRNA expression levels of IL-1α, IL-1β, IL-6, IL-8, and TNF-α. Additionally, we identified epitope peptides Pt7, Pt11/Pt11a, Pt17, Pt19, and Pt21 and loop peptides Pt13 and Pt18 which adjacent epitopes could also upregulate the mRNA expression levels of most proinflammatory cytokines. This suggested that these peptides may be the virulence-related sites of the OmpP2 protein, with proinflammatory activity. Further study revealed differences in the mRNA expression levels of proinflammatory cytokines, including IL-1β and IL-6, between genotype-specific epitopes, which may be responsible for pathogenic differences between different genotype strains. Here, we profiled a linear B-cell epitope map of the OmpP2 protein and preliminarily analyzed the proinflammatory activities and effects of these epitopes on bacterial virulence, providing a reliable theoretical basis for establishing a method to distinguish strain pathogenicity and to screen candidate peptides for subunit vaccines.

Buffalo breeding has become an important branch of the beef cattle industry. Hence, it is of great significance to study buffalo meat production and meat quality. However, the expression profiles of mRNA and long non-coding RNAs (lncRNA) molecules in muscle stem cells (MuSCs) development in buffalo have not been explored fully. We, therefore, performed mRNA and lncRNA expression profiling analysis during the proliferation and differentiation phases of MuSCs in buffalo. The results showed that there were 4,820 differentially expressed genes as well as 12,227 mRNAs and 1,352 lncRNAs. These genes were shown to be enriched in essential biological processes such as cell cycle, p53 signaling pathway, RNA transport and calcium signaling pathway. We also identified a number of functionally important genes, such as MCMC4, SERDINE1, ISLR, LOC102394806, and LOC102403551, and found that interference with MYLPF expression significantly inhibited the differentiation of MuSCs. In conclusion, our research revealed the characteristics of mRNA and lncRNA expression during the differentiation of buffalo MuSCs. This study can be used as an important reference for the study of RNA regulation during muscle development in buffalo.

[Objectives] To study the effects of Chinese herbal medicine feed additives on the growth performance and dietary nutrient metabolic rate of black-one chickens. [Methods] 480 pieces of 1-day-old Donglan Black-bone Chickens were selected and divided into 4 groups, with 6 replicates in each group, with 20 pieces in each replicate. Among them, group A was the control group and was fed the basal diet; the groups B, C, and D were the experimental groups, which were separately supplemented with 0.25%, 0.50% and 1.00% of Chinese herbal medicine additives in the basal diet, and the experimental period was 70 d. At the end of the feeding experiment, 24 experimental chickens with similar body weight were selected from each group, and the same design of the feeding experiment was used to continue to feed the original diet for the metabolic experiment to determine the nutrient metabolic rate. [Results] Except the 50 -70 d stage, the average daily gain (ADG ) of group B in other stages was increased by 5.00% -9.15% (P < 0.05), and the average body weight of group B at 70 d was also increased by 4.86% (P <0.05); the ADG of group C at 36-49, 1-49 and 1 - 70 d and the average individual weight at 70 d were also higher than that of group A by 5.90%, 2.66%, 2.68% and 2.57%, respectively (< >0.05) ; at 36-49 d, the average daily feed intake (ADFI) of group A was higher than that of group Bby6.04% (P <0.01), and was also higher than that of groups C and D by 5.12% and 4.13% (P <0.05), respectively; at1-49d, the ADFI of group A was higher than that of group C by 2.86% (P <0.05), and there was no significant difference between the four groups of experimental chickens at each stage (P > 0.05) ; at 22 - 35 and 1 - 70 d, the feed to gain ratio (F/G) of group B was 6.32% and 3.41% lower than that of group A (P <0.05), and at 36 -49 and 1 - 49 d, the F/G of group B was even lower; at 36 -49 d, the F/G of group C was 10.15% lower than that of group A (P <0.05), and at 1-49 d, it was also lower than that of group A by 5.29% (P < 0.01) ; there was no significant difference between the two groups at other stages. In terms of nutrient metabolism % the three different amounts of this additive have increased the metabolic rate of DM, CP, CF, NFE, CA, Ca, P, TE and other nutrients in the diet to varying degrees, especially the addition of 0.25% and 0.50% had the significant increase. [Conclusions] The addition of 0.25% Chinese herbal medicine additives in the diet can significantly improve the growth performance and main nutrient metabolic rate of Donglan Black-bone Chickens. [ABSTRACT FROM AUTHOR]