Polymorphism And Expression Of UCP3 And Its Correlation With Growth And Feed Efficiency In Wannan Yellow Chicken

UCP3(uncoupling protein 3)is a member of mitochondrial anion carrier superfamily.As an important candidate gene for regulating energy metabolism,UCP3(uncoupling protein 3)has a significant effect on energy metabolism and feed efficiency.Therefore,this experiment started with UCP3 gene and took Wannan Yellow chicken as the experimental materialand used the matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS)technology to conduct SNPs typing.The correlation analysis of different SNPs sites with average daily weight gain(ADG),average daily feed intake(ADFI),metabolic weight(MBW0.75),feed conversion rate(FCR)and residual feed intake(RFI)of Wannan Yellow chicken was detected.Meanwhile,real-time PCR was used to detect the expression of UCP3 gene in chest muscle and leg muscle of high and low RFI group of Wannan Yellow chicken.To analyze the effect of UCP3 gene variation on feed conversion and its molecular mechanism.1.In this study,a matrix-assisted laser desorption ionization time-of-flight mass spectrometry(MALDI-TOF MS)was used to classify 9 SNPs sites of UCP3 gene in a population of 768 s Wannan Yellow chickens.The results showed that rs732812451,rs732967862 and rs741215995 were homozygous.Among the other 6 sites,rs1057617105,rs1059111355,rs1059240054,rs1059443985 and rs315702809 were in hardy-weinberg equilibrium except rs15554568.The results showed that rs1057617105 was significantly correlated with ADG(P<0.05),and the ADG of GG type individuals was higher than that of GA type individuals,and the difference was significant(P<0.05).There was no significant correlation between rs1057617105 and BW98,ADFI,MBW0.75,FCR and RFI(P>0.05)and no significant difference among genotypes.The rs1059111355 locus was significantly correlated with BW98 and ADFI(P<0.05),the BW98 and ADFI of AG type individuals were significantly higher than that of AA type individuals(P<0.05),while the BW98 and ADFI of GG type individuals were not significantly correlated with AA and AG type individuals(P>0.05).The rs1059111355 locus was not significantly correlated with ADG,MBW0.75,FCR and RFI,and there was no significant difference among different genotypes.The rs1059240054 site was only significantly correlated with ADFI(P<0.05),and the ADFI of TT type individuals was significantly higher than that of CT type individuals(P<0.05).The rs1059240054 locus was not correlated with other traits,and there was no significant difference among different genotypes.The rs1059443985 site was only significantly correlated with FCR(P<0.05),and the FCR of TT type individuals was significantly higher than that of CT type individuals(P<0.05).There was no significant correlation between rs1059443985 and other growth and feed conversion traits,and there was no significant difference between different genotypes.There was no significant correlation between rs315702809 locus and all growth and feed efficiency traits of Wannan Yellow chickens(P > 0.05),and there was no significant difference between different genotypes.2.The relative expression of UCP3 gene in chest muscle and leg muscle of high and low RFI group of sanhuang chicken in southern anhui was detected by q PCR.The expression analysis showed that the expression level of UCP3 gene in the chest muscle of the low RFI group was extremely significantly lower than that of the high RFI group(P < 0.01).In the leg muscle,the expression of UCP3 gene in the low RFI group was significantly lower than that in the high RFI group(P < 0.05).Correlation analysis showed that the expression level of UCP3 m RNA in pectoral muscle was extremely positively correlated with FCR and RFI(P < 0.01).The expression of UCP3 m RNA in leg muscle was positively correlated with FCR and RFI(P < 0.05).There was no significant correlation between the expression of UCP3 m RNA in pectoral and leg muscles and average daily weight gain(ADG),average daily food intake(ADFI),and metabolic weight(MBW0.75)(P>0.05).In summary,the results of this study have important theoretical significance and practical value for improving the feed conversion rate of chickens,and will provide important theoretical basis for the genetic improvement of the feed conversion rate of chickens and molecular marker breeding.