Temporal Expression of Myogenic Regulatory Genes in Different Chicken Breeds during Embryonic Development

Abstract

The basic units of skeletal muscle in all vertebrates are multinucleate myofibers, which are formed from the fusion of mononuclear myoblasts during the embryonic period. In order to understand the regulation of embryonic muscle development, we selected four chicken breeds, namely, Cornish (CN), White Plymouth Rock (WPR), White Leghorn (WL), and Beijing-You Chicken (BYC), for evaluation of their temporal expression patterns of known key regulatory genes (Myomaker, MYOD, and MSTN) during pectoral muscle (PM) and thigh muscle (TM) development. The highest expression level of Myomaker occurred from embryonic days E13 to E15 for all breeds, indicating that it was the crucial stage of myoblast fusion. Interestingly, the fast-growing CN showed the highest gene expression level of Myomaker during the crucial stage. The MYOD gene expression at D1 was much higher, implying that MYOD might have an important role after hatching. Histomorphology of PM and TM suggested that the myofibers was largely complete at E17, which was speculated to have occurred because of the expression increase in MSTN and the expression decrease in Myomaker. Our research contributes to lay a foundation for the study of myofiber development during the embryonic period in different chicken breeds.

DNA Demethylation of Myogenic Genes May Contribute to Embryonic Leg Muscle Development Differences between Wuzong and Shitou Geese

“…It was reported that CnAα , NFATc3 , and IGF-1 mRNA, which is involved in the regulation of myocyte hypertrophy and fiber type specificity, were detected as early as embryonic day 13, and the highest level was also found at this stage in both pectoral and leg muscle of Gaoyou and Jinding ducks [ 26 ]. A recent study investigated known key regulatory genes during pectoral and leg muscle development in Cornish, White Plymouth Rock, White Leghorn, and Beijing-You Chickens, and found that the highest expression level of Myomaker occurred from embryonic days E13 to E15 for all breeds, indicating that it was the crucial stage of myoblast fusion [ 27 ]. These findings indicate that E15 or earlier embryonic stages may also be crucial stages regulating embryonic skeletal muscle development in geese, which needs further investigation.…”

In ovo probiotic supplementation promotes muscle growth and development in broiler embryos

“…The right PMM was collected in RNAlater (Qiagen, Germantown, MD) and stored at −80°C until further processing ( Zammit et al, 2006 ; Gu et al, 2022 ). RNA was extracted using RNeasy minikit (Qiagen) according to the manufacturer's protocol, and RNA quality was determined using the Nanodrop (Eppendorf, Enfield, CT).…”

Physiological effects of in ovo delivery of bioactive substances in broiler chickens

“…The fusion of myoblasts is performed by a membrane activator called myomaker, which is required for the formation of multinucleate fibers (73). In chickens, the myomaker gene is highly expressed from e12 to e15 and decreased to nearly zero at hatch, confirming that muscle fiber types are determined during the embryonic development and do not change during the post-hatch period (74). The fiber number and density contribute to muscle growth and weight during post-hatch (75).…”