山羊SURF4表达特征分析及其对肌内前体脂肪细胞分化的影响OA

The Surfeit locus protein 4(SURF4)gene,a member of the highly conserved surfeit gene family,functions as a cargo receptor that mediates protein transport and participates in lipid synthesis and metabolism.This study aimed to clone the SURF4 gene sequence from goats(Capra hircus),analyze its tissue expression profile,and investigate its role in intramuscular adipocyte differentiation.Using one-year-old Jianzhou Big-ear male goats as experimental subjects,this study performed RT-PCR to clone the complete CDS of goat SURF4 and conducted bioinformatics analysis of the obtained sequence.qPCR was employed to construct the tissue expression profile.An overexpression vector(pEGFP-N1-SURF4)was constructed and transfected into intramuscular adipocytes to evaluate its effects on adipocyte differentiation through morphological(Oil Red O staining)and molecular analyses.The results showed that the cloned goat SURF4 gene sequence was 1089 bp,with an 810 bp CDS region encoding 269 amino acids.SURF4 was ubiquitously expressed in heart,liver,spleen,and lung tissues,with significantly higher expression in the liver(P＜0.01).Overexpression of SURF4 markedly promoted lipid accumulation in intramuscular adipocytes and activated adipogenic pathways:mRNA levels of CCAAT/enhancer-binding protein alpha(C/EBPα)and peroxisome proliferator-activated receptor gamma(PPARγ)were dramatically upregulated(P＜0.01),while sterol regulatory element-binding protein 1(SREBP1)transcription increased significantly(P＜0.05).Key lipid synthesis markers—adipocyte fatty acid-binding protein 4(FABP4)and fatty acid synthase(FASN)—also showed extreme upregulation(P＜0.01).In conclusion,SURF4 overexpression enhances intramuscular adipocyte differentiation in goats.This study provides a theoretical foundation for elucidating the biological role and molecular mechanisms of SURF4 in regulating intramuscular fat deposition.