Changes of mRNA, miRNA and lncRNA expression contributing to skeletal muscle differences between fetus and adult Mongolian horses.

The growth and development of myofibers, as the fundamental units comprising muscle tissue, and their composition type are indeed among the most crucial factors influencing skeletal muscle types. Muscle fiber adaptation is closely associated with alterations in physiological conditions. Muscle fiber types undergo dynamic changes in fetus and adult horses. Our aim is to investigate the mechanisms influencing the differences in muscle fiber types between fetal and adult stages of Mongolian horses. The study investigated the distribution of muscle fiber types within longissimus dorsi muscle of fetus and adult Mongolian horses. A total of 652 differentially expressed genes (DEGs), 476 Differentially expressed lncRNAs (DELs), and 174 Differentially expressed miRNAs (DEMIRs) were identified using deep RNA-seq analysis. The results of functional analysis reveal the transformations in muscle fiber type from the fetal to adult stage in Mongolian horses. The up-regulated DEGs were implicated in the development and differentiation of muscle fibers, while down-regulated DEGs were associated with muscle fiber contraction, transformation, and metabolism. Additionally, connections between non-coding RNA and mRNA landscapes were identified based on their functional alterations, some non-coding RNA target genes may be associated with immunity. These data have broadened our understanding of the specific roles and interrelationships among regulatory molecules involved in Mongolian horse development, this provides new perspectives for selecting and breeding superior individuals and for disease prevention.

Melatonin promotes proliferation of Inner Mongolia cashmere goat hair follicle papilla cells through Wnt10b.

The study demonstrated that melatonin (MT) can induce the development of secondary hair follicles in Inner Mongolian cashmere goats through the Wnt10b gene, leading to secondary dehairing. However, the mechanisms underlying the expression and molecular function of Wnt10b in dermal papilla cells (DPC) remain unknown. This research aimed to investigate the impact of MT on DPC and the regulation of Wnt10b expression, function, and molecular mechanisms in DPC. The findings revealed that MT promotes DPC proliferation and enhances DPC activity. Co-culturing DPC with overexpressed Wnt10b and MT showed a significant growth promotion. Subsequent RNA sequencing (RNA-seq) of overexpressed Wnt10b and control groups unveiled the regulatory role of Wnt10b in DPC. Numerous genes and pathways, including developmental pathways such as Wnt and MAPK, as well as processes like hair follicle morphogenesis and hair cycle, were identified. These results suggest that Wnt10b promotes the growth of secondary hair follicles in Inner Mongolian cashmere goats by regulating crucial factors and pathways in DPC proliferation.

A genome-wide landscape of mRNAs, miRNAs, lncRNAs, and circRNAs of skeletal muscles during dietary restriction in Mongolian horses.

The proportion of different muscle fibers is essential for the horse breed's aptitude for athletic activities. Adaptation of locomotor muscle is correlated with altered physiologic conditions. To investigate the adaptive changes of muscle fiber phenotype and transcriptome in horse skeletal muscle during dietary restriction (DR). The muscle fiber type distribution and deep RNA-seq analysis of detecting differentially expressed mRNAs (DEGs), miRNA (DEMIRs), lncRNAs (DELs), circRNAs (DECs), and their function analysis were investigated in gluteus medius muscle of Mongolian horses during DR. A total of 1433 DEGs, 5 DEMIRs, 329 DELs, and 53 DECs were identified. Differing from non-uniform muscle fiber type changing, functional enrichment analysis showed that most downregulated DEGs were associated in muscle contraction, fuel energy metabolism, and protein balance. Linkages between non-coding RNA and mRNA landscape were detected from their functional changes. Our study provides new insights into the expressional changes of mRNA and non-coding RNA in horse skeletal muscles during DR, which might improve our understanding of the molecular mechanisms regulating muscle adaption during DR for racing horses.

Melatonin Regulates the Periodic Growth of Cashmere by Upregulating the Expression of Wnt10b and ß-catenin in Inner Mongolia Cashmere Goats.

Secondary hair follicle growth in cashmere goats has seasonal cycle changes, and melatonin (MT) has a regulatory effect on the cashmere growth cycle. In this study, the growth length of cashmere was measured by implanting MT in live cashmere goats. The results indicated that the continuous implantation of MT promoted cashmere to enter the anagen 2 months earlier and induce secondary hair follicle development. HE staining of skin tissues showed that the number of secondary hair follicles in the MT-implanted goats was significantly higher than that in the control goats (P < 0.05). Transcriptome sequencing of the skin tissue of cashmere goats was used to identify differentially expressed genes: 532 in February, 641 in October, and 305 in December. Fluorescence quantitative PCR and Western blotting results showed that MT had a significant effect on the expression of Wnt10b, ß-catenin, and proteins in the skin tissue of Inner Mongolia cashmere goats. This finding suggested that MT alters the cycle of secondary hair follicle development by changing the expression of related genes. This research lays the foundation for further study on the mechanism by which MT regulates cashmere growth.