The objectives of the present study were to identify additional genes that may play important roles in the regulation of skeletal muscle growth and development, and to provide fundamental information for understanding the underlying molecular mechanisms. Eighteen cDNA libraries were constructed from the longissimus muscle of Polled Dorset (PD) and Small-tailed Han (SH) fetuses. To reveal the differences between the two species, we analyzed the differences in gene expression in 60-, 90- and 120-day fetal skeletal muscle by applying Agilent ovine genome-wide microarray.
The phosphoglucomutase 1 (PGM1) gene was differentially expressed in tissues of Chinese Meishan and Large White pigs. In this study, the promoter region, expression profile, and genetic mutations of the gene were determined. Expression of a 5'-deletion in both C2C12 and PK-15 cells showed that a negative regulatory element was at -1871 to +185 bp and a positive regulatory element was at -1158 to +185 bp. Among the different types of muscle fibers, PGM1 had the highest expression in both longissimus dorsi and biceps femoris.
MSTN, IGF-І(insulin-like growth factor-І) and IGF-II (insulin-like growth factor-II) regulate skeletal muscle growth. This study investigated the effects of different dietary intake levels on skeletal muscles. Sheep was randomly assigned to 3 feeding groups: 1) the maintenance diet (M), 2) 1.4 x the maintenance diet (1.4M), and 3) 2.15 x the maintenance diet (2.15M). Before slaughtering the animals, blood samples were collected to measure plasma urea, growth hormone, and insulin concentrations.
We examined the expression of myosin heavy chain (MyHC) isoforms and forkhead box transcription factor O1 (FoxO1) in porcine soleus and extensor digitorum longus (EDL) muscles to clarify the correlation of FoxO1 and the relative abundance of transcripts of MyHC isoforms. Soleus muscle was found to be redder than EDL muscles in pigs, and immunohistochemical fast MyHC staining showed more oxidative type I fibers compared to EDL.
Macro- and microarrays are well-established technologies to determine gene functions through repeated measurements of transcript abundance. We constructed a chicken skeletal muscle-associated array based on a muscle-specific EST database, which was used to generate a tissue expression dataset of ~4500 chicken genes across 5 adult tissues (skeletal muscle, heart, liver, brain, and skin). Only a small number of ESTs were sufficiently well characterized by BLAST searches to determine their probable cellular functions.