The sirtuins constitute a group of histone deacetylases reliant on NAD⁺ for their activity that have gained recognition for their critical roles as regulators of numerous biological processes. These enzymes have various functions in skeletal muscle biology, including development, metabolism, and the body's response to disease. This comprehensive review seeks to clarify sirtuins' complex role in skeletal muscle metabolism, including glucose uptake, fatty acid oxidation, mitochondrial dynamics, autophagy regulation, and exercise adaptations. It also examines their critical roles in developing skeletal muscle, including myogenesis, the determination of muscle fiber type, regeneration, and hypertrophic responses. Moreover, it sheds light on the therapeutic potential of sirtuins by examining their impact on a range of skeletal muscle disorders. By integrating findings from various studies, this review outlines the context of sirtuin-mediated regulation in skeletal muscle, highlighting their importance and possible consequences for health and disease.

As societal progress elevates living standards, the focus on meat consumption has shifted from quantity to quality. In broiler production, optimizing meat quality has become paramount, prompting efforts to refine various meat attributes. Recent advancements in sequencing technologies have revealed the genome’s complexity, surpassing previous conceptions. Through experimentation, numerous genetic elements have been linked to crucial meat quality traits in broiler chickens. This review synthesizes the current understanding of genetic determinants associated with meat quality attributes in broilers. Researchers have unveiled the pivotal insights detailed herein by employing diverse genomic methodologies such as QTL-based investigations, candidate gene studies, single-nucleotide polymorphism screening, genome-wide association studies, and RNA sequencing. These studies have identified numerous genes involved in broiler meat quality traits, including meat lightness (COL1A2 and ACAA2), meat yellowness (BCMO1 and GDPD5), fiber diameter (myostatin and LncIRS1), meat pH (PRDX4), tenderness (CAPN1), and intramuscular fat content (miR-24-3p and ANXA6). Consequently, a comprehensive exploration of these genetic elements is imperative to devise novel molecular markers and potential targets, promising to revolutionize strategies for enhancing broiler meat quality.

Excessive abdominal fat deposition (AFD) in poultry reduces meat yield and efficiency. The gut microbiota regulates AFD through shifts in microbial composition and the production of metabolites. Reduced microbial diversity and fat-promoting taxa (e.g., Methanobrevibacter, Escherichia-Shigella) elevate AFD, while lean-linked bacteria (e.g., Bacteroides, Oscillospira) promote leanness. Dietary interventions, including botanical ingredients (e.g., honeycomb flavonoids elevating short-chain fatty acid producers), fermented feeds (e.g., cottonseed meal enriching butyrogenic taxa), probiotics (e.g., Lactobacillus johnsonii downregulating PPARγ/FAS), and additives (bile acids activating FXR/PPARα), modulate gut microbiota to reduce AFD by enhancing barrier function, suppressing pathogens, and regulating lipid metabolism. Fecal microbiota transplantation confirms microbiota-driven AFD reduction but faces donor-matching challenges. Breed-specific microbial signatures and context-dependent outcomes inform precision strategies to improve feed efficiency and lean yield.

Background: The testis, a critical reproductive organ in male animals, is responsible for sperm production and androgen secretion. Testis weight often correlates with reproductive performance, yet the genetic factors influencing testicular traits in chickens remain unclear. Methods: Previous genome-wide association studies (GWAS) have identified key genes affecting testicular traits in Kangle Yellow chickens, along with the associated regulatory pathways and Gene Ontology (GO) terms, through bioinformatic analyses. In this study, we utilized the existing literature, full-length transcriptome data, and proteome analyses to select key candidate genes. Results: We identified 13 associated markers for chicken testicular traits with 262 candidate genes. Nine candidate genes were found to regulate chicken testicular traits referred to integrated analysis, including CDH3, ZFPM1, CFAP52, ST6GAL1, IGF2BP2, SPG7, CDT1, NFAT5, and OPRK1. Physical interactions among these genes were also observed, implicating mechanisms such as cell adhesion molecules and neuroactive ligand–receptor interaction. Conclusions: These findings provide a genetic basis for improving testicular traits in Chinese native chicken breeds.

A central challenge in functional genomics is understanding the difference between correlative transcriptomic observations and definitive causal understanding of gene function in vivo. Poultry skeletal muscle, a system of significant agricultural and biological importance, demonstrates this challenge. While transcriptomic studies have cataloged extensive RNA expression dynamics during muscle development and in growth-related myopathies like wooden breast, establishing causative roles for these molecules is lacking. This review synthesizes how advanced genetic tools are now enabling a shift from correlation to causation in avian muscle biology. We detail how viral vectors (e.g., adenovirus, lentivirus, and RCAS) and CRISPR/Cas9 systems have provided direct in vivo validation of the functional roles of specific mRNAs, miRNAs, lncRNAs, and circRNAs in regulating myogenesis, hypertrophy, and atrophy. We contrast this success in fundamental biology with the study of myopathies, which remains largely descriptive. Here, a wealth of transcriptomic data has identified dysregulated pathways, including ECM remodeling, metabolism, and inflammation, but functional validation for most candidates is absent. We argue that the critical next step is to apply this established functional genomics toolkit to disease models. By defining causal mechanisms, this research will not only address a major agricultural issue but also provide a model for using genetic tools to dissect complex traits in a post-genomic era.

Streptococcus agalactiae ATCC 27956 is a highly contagious Gram-positive bacterium that causes mastitis, has a high infectivity for mammary epithelial cells, and becomes challenging to treat. However, the molecular interactions between it and mammary epithelial cells remain poorly understood. This study analyzed differential gene expression in mammary epithelial cells with varying levels of S. agalactiae infection using UID-Dual transcriptome sequencing and bioinformatics tools. This study identified 211 differentially expressed mRNAs (DEmRNAs) and 452 differentially expressed lncRNAs (DElncRNAs) in host cells, primarily enriched in anti-inflammatory responses, immune responses, and cancer-related processes. Additionally, 854 pathogen differentially expressed mRNAs (pDEmRNAs) were identified, mainly enriched in protein metabolism, gene expression, and biosynthesis processes. Mammary epithelial cells activate pathways, such as the ERK1/2 pathway, to produce reactive oxygen species (ROS) to eliminate bacteria. The bacteria disrupt the host’s innate immune mechanisms by interfering with the alternative splicing processes of mammary epithelial cells. Specifically, the bacterial genes of tsf, prfB, and infC can interfere with lncRNAs targeting RUNX1 and BCL2L11 in mammary epithelial cells, affecting the alternative splicing of target genes and altering normal molecular regulation.