MED4 gene positively affects preadipocyte differentiation in Chinese red steppe cattle

Background:The regulatory genes related to lipid metabolism affect the intramuscular fat(IMF)content and improve meat quality traits.Mediator Complex Subunit 4(MED4),a vitamin D receptor protein,affects vitamin D,livestock growth,carcass traits,and triglyceride deposition.However,the physiological function of the MED4 gene on bovine adipocyte differentiation remains unknown.Methods:This study explored the function of the MED4 gene in preadipocyte differentiation in Chinese Red Steppe cattle.The overexpression plasmid and the interference sequences of the MED4 gene were constructed to detect the effects of the MED4 gene on adipogenesis and biomakers using quantitative polymerase chain reaction and western blotting.Results:The MED4 gene had significantly high expression during preadipocyte differentiation(p<0.05).Overexpression of the MED4 gene increased the expression of the PPARγgene,a preadipocyte differentiation biomarker,improved cellular lipid droplets and triglycerides accumulation,and positively accelerated adipocyte maturation(p<0.05).Interference of the MED4 gene can negatively regulate preadipocyte differentiation.Conclusion:This study showed that the MED4 gene may affect the preadipocyte differentiation and adipogenesis in Chinese Red Steppe cattle by regulating the PPARγgene.

Close Association between 4685 Loci on CAPN1 Gene and Meat Tenderness

[Objective] The paper was to explore the impact of 4685 loci on CAPN1 gene of Yanbian yellow cattle and red steppe cattle on meat tenderness. [Method] The 4685 loci in 14th intron region of CAPN1 gene of Yanbian yellow cattle and red steppe cattle was conducted analysis of gene polymorphism and meat tenderness by PCR-RFLP technology, and the effect of the loci on Jilin local cattle breeds was verified. [Result] The loci had close relationship with related detection indices of meat tenderness （cooking loss, muscle fibre diameter, shear force and drip loss）, and the existence of T allele could significantly increase the tenderness level of in- dividuals, but the loci was not associated to pH value. 4685 loci was not associated to carcass traits （carcass weight, net meat weight and carcass yield ratio）, which only had certain correlation with eye muscle area. [Conclusion] The 4685 loci on CAPN1 gene of Yanbian yellow cattle and red steppe cattle had close association with meat tenderness.