Dynamic transcriptome profiles of skeletal muscle growth and development in Shaziling and Yorkshire pigs using RNA-Seq.

Abstract

We previously demonstrated that Shaziling and Yorkshire pigs differ in growth rate and meat quality. However, the molecular mechanisms responsible for such phenotypic differences remains unclear. Here, we performed a transcriptomic analysis of 36 longissimus dorsi (LM) and 36 soleus (SM) muscle samples from Shaziling and Yorkshire pigs at six postnatal stages (30, 60, 90, 150, 210, and 300 days) to explore the differences in postnatal skeletal muscle of Shaziling and Yorkshire pigs. Muscle morphological changes and the number of differentially expressed genes (DEGs) indicated the two stages of 60 to 90 d and 150 to 210 d were critical for the muscle growth and development in Shaziling pigs. The genes such as FLNC, COL1A1, NRAP, SMYD1, TNNI3, CRYAB, and PDLIM3 played vital roles in the muscle growth, and the genes such as CCDC71L, LPIN1, CPT1A, UCP3, NR4A3, and PDK4 played dominant roles in the lipid metabolism. Additionally, in contrast to the LM, the percentage of slow-twitch muscle fibers in the SM of both breeds consistently decreased from 30 to 150 days of age, but there was a significant rebound at 210 days of age. However, the percentage of slow-twitch muscle fibers in the SM of Shaziling pigs was higher than that in Yorkshire pigs, which may be associated with the calcium signaling pathway and PPARβ/δ signaling pathway. This study detected two critical periods and many functional genes for the muscle growth and development of Shaziling pigs, and showed differences in muscle fiber characteristics between Shaziling and Yorkshire pigs. This article is protected by copyright. All rights reserved.