Study on the developmental expression of Lbx1 gene in longissimus dorsi of Mashen and Large White pigs

In the present study we investigated the developmental expression patterns of Lbx1 gene in skeletal muscle of different genetic profile pigs after birth. A total of 28 Mashen pigs and 28 Large White pigs from seven development stages of 1, 30, 60, 90, 120, 150, 180 d were used and the expression patterns in longissimus dorsi were studied by quantitative real time-polymerase chain reaction and western blot in this study. The results showed that the breed, age, and the interaction of breed and age significantly affected the Lbx1 mRNA and protein expressions in longissimus dorsi (P<0.05). In Large White, the amount of Lbx1 protein was increased from new birth to 30 d, and decreased after 30 d to the lowest level at 180 d. In Mashen pig, Lbx1 protein level showed an increase trend with the age increase before 90 d, then decreased to the lowest level at 120 d, and then gradually increased upwards to the expression peak at 180 d. Before 120 d, the Lbx1 protein content in Large White was higher than that in Mashen pig, except for at 60 d. Afterwards, the protein level in Mashen was higher than that in Large White. The Lbx1 expression pattern was related to the age and genetic profiles of Mashen and Large White pigs, which indicates that Lbx1 could participate in the muscle development through activating the satellite cells of skeletal muscle after birth.