Molecular Cloning, Expression Profiling, and Marker Validation of the Chicken Myoz3 Gene

Research Note: Association of IGF-1R gene polymorphism with egg quality and carcass traits of quail (Coturnix Japonica)

Insulin-like growth factor 1 receptor (IGF-1R) gene is the main effector of insulin-like growth factor (IGF), which plays an important role in growth, development and reproduction of the animal organism. This study aimed to investigate the association of IGF-1R gene single nucleotide polymorphisms (SNPs) with egg quality and carcass traits of quail by direct sequencing. In this study, genomic DNA was extracted from quail blood samples of 46 Chinese yellow (CY) quail, 49 Beijing white (BW) quail and 48 Korean (KO) quail strains. Egg quality and carcass traits were measured and used for IGF-1R gene analysis in 3 quail strains. The results showed that 2 SNPs (A57G and A72T) of the IGF-1R gene were detected in 3 quail strains. The A57G was significantly associated with yolk width (YWI) in BW strain (P < 0.05). Whereas A72T was significantly associated with egg shell thickness (EST) in BW strain (P < 0.05), and significantly associated with egg weight (EW), egg long (EL), and egg short (ES) in KO strain (P < 0.05). Haplotypes based on 2 SNPs showed significant effect on EST in 3 quail strains (P < 0.05), it also has a significant effect on EW in KO strain (P < 0.05). Meanwhile, A72T was significantly associated with liver weight (LW) and dressing percentage (DP) in 3 strains (P < 0.05). Haplotypes showed significant effect on LW (P < 0.05). Therefore, the IGF-1R gene may be a molecular genetic marker to improve egg quality and carcass traits in quails.

Integrated multi-omic data reveal the potential molecular mechanisms of the nutrition and flavor in Liancheng white duck meat

The Liancheng white (LW) duck is one of the most valued Chinese indigenous poultry breeds. Its meat is rich in nutrients and has distinct flavors, but the molecular mechanisms behind them are unknown. To address this issue, we measured and compared multi-omic data (genome, transcriptome, and metabolome) of breast meat from LW ducks and the Mianyang Shelduck (MS) ducks. We found that the LW duck has distinct breed-specific genetic features, including numerous mutant genes with differential expressions associated with amino acid metabolism and transport activities. The metabolome driven by genetic materials was also seen to differ between the two breeds. For example, several amino acids that are beneficial for human health, such as L-Arginine, L-Ornithine, and L-lysine, were found in considerably higher concentrations in LW muscle than in MS duck muscle (p < 0.05). SLC7A6, a mutant gene, was substantially upregulated in the LW group (p < 0.05), which may lead to excessive L-arginine and L-ornithine accumulation in LW duck meat through transport regulation. Further, guanosine monophosphate (GMP), an umami-tasting molecule, was considerably higher in LW muscle (p < 0.05), while L-Aspartic acid was significantly abundant in MS duck meat (p < 0.05), showing that the LW duck has a different umami formation. Overall, this study contributed to our understanding of the molecular mechanisms driving the enriched nutrients and distinct umami of LW duck meat, which will provide a useful reference for duck breeding.

A Proteomic Study for the Discovery of Beef Tenderness Biomarkers and Prediction of Warner-Bratzler Shear Force Measured on Longissimus thoracis Muscles of Young Limousin-Sired Bulls

Beef tenderness is of central importance in determining consumers’ overall liking. To better understand the underlying mechanisms of tenderness and be able to predict it, this study aimed to apply a proteomics approach on the Longissimus thoracis (LT) muscle of young Limousin-sired bulls to identify candidate protein biomarkers. A total of 34 proteins showed differential abundance between the tender and tough groups. These proteins belong to biological pathways related to muscle structure, energy metabolism, heat shock proteins, response to oxidative stress, and apoptosis. Twenty-three putative protein biomarkers or their isoforms had previously been identified as beef tenderness biomarkers, while eleven were novel. Using regression analysis to predict shear force values, MYOZ3 (Myozenin 3), BIN1 (Bridging Integrator-1), and OGN (Mimecan) were the major proteins retained in the regression model, together explaining 79% of the variability. The results of this study confirmed the existing knowledge but also offered new insights enriching the previous biomarkers of tenderness proposed for Longissimus muscle.

Transcriptome Profiling Associated with Carcass Quality of Loin Muscles in Crossbred Pigs

Carcass quality traits, such as lean depth and loin depth, are of extreme economic importance for the swine industry. This study aimed to identify the gene expression pattern related to carcass quality in crossbred pigs ((Landrace × Yorkshire) × Duroc). In total, 20 crossbred pigs were used in this study and they were divided into two groups (class I grade, n = 10; class II grade, n = 10) based on the carcass grades. Total RNA samples extracted from the loin muscles of both groups were submitted for RNA-seq. The quality assessment of the sequencing reads resulted in 25,458 unigenes and found 12,795 candidate coding unigenes with homology to other species after annotation. Differentially expressed gene (DEG) analysis of the two groups revealed 282 up-regulated and 189 down-regulated genes (p ≤ 0.01), linked to tissue development, striated muscle tissue development, tissue morphogenesis, and lipid metabolic process gene ontology (GO) terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis highlighted genes related to the calcium signaling pathway, melanogenesis, the sphingolipid signaling pathway, the apelin signaling pathway, and the mTOR signaling pathway. We constructed an expressed gene profile, which may serve as a resource for genomic studies focused on uncovering the molecular mechanisms underlying carcass quality in crossbred pigs.

Transcriptomic analysis of chicken Myozenin 3 regulation reveals its potential role in cell proliferation

Embryonic muscle development and fibre type differentiation has always been a topic of great importance due to its impact on both human health and farm animal financial values. Myozenin3 (Myoz3) is an important candidate gene that may regulate these processes. In the current study, we knocked down and overexpressed Myoz3 in chicken embryonic fibroblasts (CEFs) and chicken myoblasts, then utilized RNA-seq technology to screen genes, pathways and biological processes associated with Myoz3. Multiple differentially expressed genes were identified, including MYH10, MYLK2, NFAM1, MYL4, MYL9, PDZLIM1; those can in turn regulate each other and influence the development of muscle fibres. Gene ontology (GO) terms including some involved in positive regulation of cell proliferation were enriched. We further validated our results by testing the activity of cells by cell counting kit-8(CCK-8) and confirmed that under the condition of Myoz3 overexpression, the proliferation rate of CEFs and myoblasts was significantly upregulated, in addition, expression level of fast muscle specific gene was also significantly upregulated in myoblasts. Pathway enrichment analysis revealed that the PPAR (Peroxisome Proliferator-Activated Receptor) pathway was enriched, suggesting the possibility that Myoz3 regulates muscle fibre development and differentiation through the PPAR pathway. Our results provide valuable evidence regarding the regulatory functions of Myoz3 in embryonic cells by screening multiple candidate genes, biological processes and pathways associated with Myoz3.