Dietary Morus alba L. leaf supplementation improves hepatic lipid accumulation of laying hens via downregulating CircACACA

Emerging roles of circular RNAs on the regulation of production traits in chicken

Chickens are vital agricultural animals that supply a significant portion of the protein consumed by humans. In society today, enhancing the productive performance of chickens in a safe and efficient manner has become a central focus of research. This performance is determined by various production traits that are primarily influenced by multiple factors, including epigenetics-a critical aspect of gene regulation. Circular RNAs (circRNAs), a unique class of non-coding RNAs, have emerged as key epigenetic regulators. Recent studies have demonstrated that circRNAs are extensively engaged in numerous production traits, which include skeletal muscle formation, fat deposition, ovarian follicle development, liver function, bone development, immunity, and resistance to environmental stress. These processes play crucial roles in determining the overall productivity of chickens. Given the significance of circRNAs in these various traits, this article provides a comprehensive review of the functional circRNAs associated with different traits in chickens, serving as a valuable theoretical reference for future research. Further investigation into the role of circRNAs may reveal novel insights into the molecular mechanisms underlying key economic traits in chickens and pave the way for innovative strategies in molecular breeding aimed at enhancing chicken productive performance.

The Effect of Mulberry Silage Supplementation on the Carcass Fatness and Long-Chain Fatty Acid Composition of Growing Lambs Compared with Traditional Corn Silage

Lamb meat has become very popular with consumers in recent years due to its nutritional benefits. As a lean red meat, lamb is an important natural source of polyunsaturated and saturated fatty acids, which can be modified by adjustments in livestock feed. This study used proteomic and metabolic analyses to compare a basal ration supplemented with either mulberry silage or corn silage. Supplementation with mulberry silage led to a reduction in subcutaneous carcass fatness compared with corn silage. Additionally, changes in the proteome associated with fatty acid metabolism and oxidation resulted in decreased levels of saturated and trans fatty acids, while significantly increasing the levels of α-linolenic acid (ALA) and oleic acid and reducing linoleic acid content.

circUSP13 facilitates the fast-to-slow myofiber shift via the MAPK/ERK signaling pathway in goat skeletal muscles

Understanding how skeletal muscle fiber proportions are regulated is essential for understanding muscle function and improving the quality of mutton. While circular RNA (circRNA) has a critical function in myofiber type transformation, the specific mechanisms are not yet fully understood. Prior evidence indicates that circular ubiquitin-specific peptidase 13 (circUSP13) can promote myoblast differentiation by acting as a ceRNA, but its potential role in myofiber switching is still unknown. Herein, we found that circUSP13 enhanced slow myosin heavy chain (MyHC-slow) and suppressed MyHC-fast expression in goat primary myoblasts (GPMs). Meanwhile, circUSP13 evidently enhanced the remodeling of the mitochondrial network while inhibiting the autophagy of GPMs. We obtained fast-dominated myofibers, via treatment with rotenone, and further demonstrated the positive role of circUSP13 in the fast-to-slow transition. Mechanistically, activation of the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway significantly impaired the slow-to-fast shift in fully differentiated myotubes, which was restored by circUSP13 or IGF1 overexpression. In conclusion, circUSP13 promoted the fast-to-slow myofiber type transition through MAPK/ERK signaling in goat skeletal muscle. These findings provide novel insights into the role of circUSP13 in myofiber type transition and contribute to a better understanding of the genetic mechanisms underlying meat quality.