Temporal expression of transforming growth factor-[beta]2 and myostatin mRNA during embryonic myogenesis in Indian broilers

• Published in: Research in veterinary science Vol. 82; no. 1; p. 50
• Main Authors: Saxena, V.K, Sundaresan, N.R, Malik, Faizi, Ahmed, K.A, Saxena, M, kumar, Sumit, Nandedkar, P.V, Singh, R.V
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Limited 01.02.2007
• Subjects: Cell adhesion & migration; Embryos; Muscular system; Musculoskeletal system; Proteins; Studies; Veterinary medicine
• ISSN: 0034-5288; 1532-2661
• DOI: 10.1016/j.rvsc.2006.05.005

TGF-β2 and myostatin, the members of TGF family, act through both autocrine and paracrine mechanisms to regulate the growth and differentiation at various developmental stages in chicken. The kinetics and expression profile of these two growth factors were investigated by semi-quantitative RT-PCR, during the myogenesis of Indian broiler chickens. Total RNA was isolated from whole embryos on each of embryonic days (E) 0-6 (n =3 per day) and from the biceps femoris muscle at E7-E18 (n =3 per day). The expression of TGF-β2 was noticed on E2 that remained at the same level until E6. In biceps femoris muscle, higher level of TGF-β2 expression was observed during E7-E12, which decreased gradually thereafter. These findings suggested that TGF-β2 might be a regulatory factor participating in the myogenesis of chicken embryos. Initial myostatin expression was noticed on E1, even before the myogenic lineage is established in embryo. This finding suggested an additional role of myostatin in early chicken embryo development, other than myogenesis. Furthermore, myostatin expression was significantly higher on E3 as compared to earlier studies, where initial higher level was observed at E2, suggesting the differential expression of myostatin among breeds. Higher and almost static myostatin expression was noticed in biceps femoris muscle during the entire period of myogenesis (E7-E18). In the present study, the ontogeny of myostatin expression coincided with myogenesis of chicken. Therefore, it may be hypothesized that myostatin is not only a major determinant of muscle mass, but also involved in early embryogenesis in chickens.