Studies On The Genetic Effects And Mechanism Of PLIN Gene On Growth,Carcass And Meat Quality Traits And Their Expression Characterization In Jinmao Hua Chicken

In the present study,PCR-SSCP method was used to detect the SNPs of PLIN gene in the core group of Jinmao Hua chicken.The general linear model was used to analyze its relationship with growth traits,carcass traits and meat quality traits.Additional,the developmental pattern of PLIN mRNA expression in different tissues in different growth stages were determined by relative quantitative RT-PCR.The main results were as follows:1.The PLIN gene was selected as the candidate gene,and the polymorpHism of exon region of the gene was detected.The results showed that two mutations of T910C and A920G were detected in exon 3,the former mutation did not result in a change in the encoded amino acid and was a synonymous mutation;the latter mutation resulted in a change in the amino acid encoding the amino acid from lysine to glutamic acid,result in three genotypes,including AA,AB and BB,and a G3488A mutation was detected in exon 8,the mutation sites caused no change in the encoded amino acid,result in two genotypes,including CC and CD.Association analysis showed that the body weight of AB individuals was significantly higher than that of AA genotype at 4,6,8 and 10 weeks of age(P<0.01)and BB genotype at 10 weeks of age(P<0.05),suggesting that AB individuals were predominant individuals.There was no difference in growth traits between CC and CD genotype(P>0.05).In female chickens,AB genotype was significantly higher than AA and BB genotypes at half-net rate,abdominal fat weight,head weight,weight,liver weight,spleen weight,and wing weight(P<0.05).In male chickens,AA genotype was significantly higher than AB genotype(P<0.05).There were no significant differences between CC and CD genotypes in female chickens.For male chickens,the abdominal fat weight of CC type was significantly lower than that of CD type(P<0.05),while the breast muscle rate of CC genotype was significantly higher than CD genotype(P<0.05).For the meat quality traits,AA and AB genotype were significantly higher than BB genotype female chickens in the leg muscle water content.In male chicken,the leg muscle water content of AB genotype was significantly higher than that of AA and BB genotype.In female chicken,the crude fat content of CC genotype breast muscle was significantly higher than that of CD genotype(P<0.05),In male chicken,CC genotype were significantly higher than CD genotype at the shear stress and crude protein content of the pectoral muscle(P<0.05),and very significantly higher than CD genotype at leg muscle moisture content(P<0.01).2.The polymorpHism of exon 5 of PLIN gene was detected,and five mutations were found.C1889T,T1904C,and C1922T were located in exon 5,and A2014G and C2020T were located in the introns 5 adjacent to exon 5.These mutations result in no amino acids change,which indicated that they were synonymous mutations.The haplotype combination analysis of the female chicken populations showed that the haplotype combinations H2H5 and H3H3 were the significantly higher than other haplotype combinations(P<0.05 or P<0.01),and the haplotype combinations of H1H5 and H2H2 were significantly lower than other haplotypes(P<0.05 or P<0.01)in the growth traits.Therefore,H2H5 and H3H3 were the dominant genotypes and H1H5 and H2H2 were the inferior genotypes for growth traits.In terms of carcass traits of female chicken,The haplotype combination of H1H3 and H4H4 was the dominant haplotype combination for abdominal fat weight,and the haplotype combination was H2H6 the dominant haplotype combination for leg muscle rate.When it comes to male chicken,haplotype combination of H1H3 was the dominant haplotype combination forabdominal fat weight.For meat quality traits,the haemolage of female chicken was significantly higher than that of other haplotypes in haplotype H4H4(P<0.05),Leg muscle in the haplotype H2H6 was higher,In the cock,chest muscle color in haplotype H1H3 higher,Leg muscle color in H1H4 higher;Hams leg muscle pH in haplotype H1H4 was significantly higher,In cock,chest muscle pH in the haplotype H1H1 were higher;The water level of the chest muscle of the hen was higher than that of the haplotype H2H2 and H4H4.The content of inosinic acid was different only in the leg muscle of the hen and H1H4 was the dominant haplotype combination;The haplotype combinations of crude fat content in hen cramp muscle were H1H4 and H1H3,respectively.Therefore,PLIN gene polymorpHism had significant or significant effects on the growth,slaughter and meat quality traits(P<0.05 or P<0.01).3.The expression of PLIN gene at different growth stages and tissues of Jinmao Hua Chicken was determined.The results showed that PLIN gene was highly expressed in heart,liver and chest muscle,While the expression level in breast muscle was higher than that in leg muscle.The expression of mRNA in the liver showed an increasing trend at the late growth stage,In the roosters,the expression levels in the pectoralis and thigh muscles decreased first and then increased,While the expression level in hens,chest muscles and leg muscles increased first and then decreased.