While restricting nutrition can improve diseases related to the digestive tract, excessive restriction of food intake can also lead to malnutrition and delayed physical growth. Therefore, this brings the demand to study the effect and potential mechanism of restricted feeding on skeletal muscle development in rabbits. This study utilized hematoxylin-eosin (HE) staining to detect muscle fiber area which depicted significant reduction in skeletal muscle fiber upon 30% feed restriction (p < 0.05). The control group and 30% feed restricted group showed 615 deferentially expressed genes (DEGs). Through the GO and KEGG functional enrichment analysis demonstrated 28 DEGs related to muscle development. KEGG analysis showed enrichment of pathways including PI3K/Akt signaling pathway, MAPK signaling pathway, and Hedgehog signaling pathway. Further, the full length of troponin I1, slow skeletal type (TNNI1) was cloned. We studied the expression of skeletal muscle differentiation-related genes such as MyoD, Myf5 gene and Desmin. Specifically, the TNNI1 gene overexpression and knockdown studies were conducted. The over-expression of TNNI1 significantly enhanced the expression of the skeletal muscle development-related genes. Contrastingly, the silencing of TNNI1 gene reduced the expression significantly. These findings showed that TNNI1 may be a regulator for regulating the expression of muscle development-related genes.
Keywords: Restricted feeding; TNNI1 gene; meat rabbits; muscle development; muscle development genes; muscle growth; muscles differentiation.