The Regulatory Effect of the SP1/IGF2BP3 Axis on the Proliferation of Porcine Skeletal Muscle Satellite Cells

HUANG Yuxin; WANG Wei; LI Yixing; TANG Zhonglin

doi:10.15933/j.cnki.1004-3268.2025.03.014

Abstract：This study investigated the effect of insulin-like growth factor 2 mRNA-binding protein 3(IGF2BP3)on the growth and development of porcine skeletal muscle and analyzed its biological function and expression regulation mechanism so as to provide a theoretical basis and candidate genes for genetic improvement in pigs.Porcine skeletal muscle satellite cells were utilized as the experimental material.RT-qPCR and Western blot were employed to measure the expression of cell proliferation marker genes PCNA、CDK4、Cyclin A2 and MKI67,and EdU and CCK-8 kits were used to detect cell proliferation viability and rate.The dual-luciferase assay of SP1 binding site mutations in the promoter region of the IGF2BP3 gene and the ChIP assay were employed to investigate the expression regulatory mechanism of the IGF2BP3 gene by the transcription factor SP1.The results showed that knocking down IGF2BP3 in porcine skeletal muscle satellite cells significantly upregulated the expression of cell proliferation marker genes,increased the proportion of EdU positive cells,and significantly increased the cell proliferation rate at 48 and 72 hours.The dual-luciferase activity was significantly reduced by mutations in the SP1 binding region,whereas the activity was significantly increased by SP1 overexpression.SP1 could bind to the promoter region of the IGF2BP3 gene.Interference with SP1 decreased IGF2BP3 expression,whereas overexpression of SP1 upregulated IGF2BP3 expression.Overexpression of SP1 partially eliminated the phenotype that knockdown of IGF2BP3 promoted proliferation of porcine skeletal muscle satellite cells.In conclusion,the transcription factor SP1 and the IGF2BP3 gene interact to regulate the proliferation of porcine skeletal muscle satellite cells.