Progress 05/01/07 to 05/01/08
Outputs
OUTPUTS: The long-range goal of this research is to improve the efficiency and the rates of muscle (meat) accretion in poultry and to identify biochemical parameters associated with enhanced muscling. Improvement in our understanding of the factors regulating body growth will lead to the development of procedures to lower production costs and assist in the identification of superior lines of turkeys and chickens for meat production. During the past year, we have been investigating the role of muscle membrane lipid composition in poultry skeletal muscle responsiveness to growth factor stimuli. We have found that membrane lipid composition does affect the expression of genes critical in muscle growth. The results from these studies are novel in that there are no reported studies as to how such membrane changes might influence growth factor receptor activity and therefore skeletal muscle growth and development. We therefore, propose that changes in the lipid composition of diets may impact muscle growth rates by influencing growth factor receptor activities. PARTICIPANTS: Dr. Douglas McFarland, South Dakota State University, is a co-PI on this research. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Changes in muscle membrane lipid composition affect the ability of these cells to replicate and form differentiated muscle structures. Nutritional dietary regimens may be able to adjusted to enhance muscle cell membrane structure leading to enhanced muscle formation and perhaps improved meat quality. Every percent improvement in breast meat yield is worth $100 million to the turkey industry, and in broilers over $300 million.
Publications
- Velleman, S.G., Li, X., Coy, C.S., and McFarland, D.C. 2008. The effect of fibroblast growth factor 2 on in vitro expression of syndecan-4 and glypican-1 in turkey satellite cells. Poult. Sci. 87:1834-1840.
- Li, X., McFarland, D.C., and Velleman, S.G. 2008. Extracellular matrix proetoglycan decorin-mediated myogenic satellite cell responsiveness to transforming growth factor-B during satellite cell proliferation and differentiation. Dom. Anim. Endocrinol. 35:263-373.
- Li, X., McFarland, D.C., and Velleman, S.G. 2008. Effect of smad3 mediated tranforming growth factor B1 signaling on satellite cell proliferation and differentiation in chickens. Poult. Sci. 87:1823-1833.
- Zhang, X., Nestor, K.E., McFarland, D.C., and Velleman, S.G. 2008. The role of syndecan-4 and attached glycosaminoglycan chains on myogenic satellite cell growth. Matrix 27:619-630.
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Progress 01/01/07 to 12/31/07
Outputs
OUTPUTS: Heparan sulfate proteoglycans (HSPG) are key components of the cell membrane and extracellular matrix of skeletal muscle cells. Two major groups of membrane-associated HSPG found in skeletal muscle are syndecans (SYN) and glypicans (GPC), both of which can regulate growth factor activities and thus modulate cell proliferation and differentiation. In the current study, the mRNA expression of a group of membrane-associated HSPG (SYN 2 through 4 and GPC 1) was investigated in embryonic pectoralis major muscle [embryonic days (ED) 14, 16, 18, 20, 22, 24] and myogenic satellite cells isolated from males of a turkey genetic line selected for increased 16-wk BW (F line) and an unselected randombred control (RBC2 line) from which the F line was developed. The mRNA expression was measured by a real-time quantitative PCR approach. The SYN 2 and SYN 4 expression exhibited a similar pattern during embryonic p. major muscle development, which remained constant from ED 14 to ED 22 and
declined sharply from ED 22 to ED 24 to a very low level. In contrast, the SYN 3 and GPC 1 expression showed a continuous decline from ED 14 to ED 24. The F line had higher SYN 2 (ED 14, 18, 20, 22), SYN 3 (ED 22), and SYN 4 (ED 22) expression than the RBC2 line. In myogenic satellite cells, initiating differentiation resulted in a decrease in SYN 2 expression and an increase in GPC 1 expression. Both SYN 3 and SYN 4 expression stayed almost constant through both the proliferation and differentiation stages. The proliferating satellite cells from the F line displayed higher SYN 4 expression than those from the RBC2 line. Collectively, the results from the current study suggest that membrane-associated HSPG are differentially expressed in both embryonic p. major muscle tissue and satellite cells isolated from F-line and RBC2-line male turkeys, implying their distinct roles in myogenesis and differing influence on muscle growth properties.
PARTICIPANTS: Dr. Douglas McFarland, Professor, South Dakota State University is the primary collaborator on this research. Dr. Caini Liu, Postdoctoral Fellow, worked on aspects of this project as part of her training.
Impacts
Per capita consumption of chicken and turkey has increased dramatically since the 1970s. Chicken consumption has increased from 40.3 pounds per person in 1970 to 82.5 pounds per person in 2003. Turkey consumption has risen from 8.1 pounds in 1970 to 17.4 pounds per person in 2003. The upward trend in poultry consumption is expected to continue. In this regard breeders are focused on maximizing growth especially for lean carcass development with an emphasis on the breast muscle. For the industry, every percent improvement in breast muscle yield is worth $100 million to the US turkey industry, and in broilers is worth over $300 to the US broiler industry. Therefore, furthering our understanding of the mechanisms regulating muscle growth will have a significant financial impact to the US poultry industry
Publications
- Velleman, S.G., Coy, C.S., and McFarland, D.C. 2007. Effect of syndecan-1, syndecan-4, and glypican-1 on turkey muscle satellite cell proliferation, differentiation, and responsiveness to fibroblast growth factor . Poult. Sci. 86:1406-1413.
- McFarland, D.C., Velleman, S.G., Pesall, J.E., and Liu, C. 2007. The role of myostatin in chicken (gallus doemsticus) myogenic satellite cell proliferation and differentiation. Gen. and Comp. Endocrinol. 151:351-357.
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