The Expression Of RBP4and Its Association Between SNP And Reproduction In Chicken

Retinol-binding protein4(RBP4) is the only transport protein for retinoids in the blood, and is a member of hydrophobic binding protein family. It plays unfungible role in storage, metabolism of retinol and transport of retinol to the target cells. RBP4is mainly produced in liver, but also synthesized in kidney, adipose tissue, endometrium ovary et.al. The transport and buffering ability of RBP4at this critical time of pregnancy makes RBP4a strong candidate gene for litter size in pigs in2001.This paper used RT-qPCR to analysis RBP4expression patterns at12,20,32and45weeks and seven tissues (heart, liver, kidney, fallopian tubes, ovaries, pituitary and hypothalamus) on three lines about SD02, SD03of Erlang Mountainous Chicken and Roman egg shell powder. We also used PCR-SSCP and sequence methods to detecte the SNPs of RBP4exon intron sequence in two lines about SD02and SD03of Erlang mountain chicken, and meanwhile, we did association analysis combined with reproductive traits.The results are as follows:The liver was advantageous tissue for RBP4in seven tissues of this three strains at four growth points. The expression of RBP4had differences between broiler and layer, but the differences were not significant. So we could not conject that RBP4was the major gene what influences egg production traits.Different expression of RBP4was detected among this three strains:Roman egg shell powder had highter expression of RBP4in pituitary and hypothalamus at12week than SD02strain of Erlang mountain chicken, and in fallopian tubes at45week than SD02and SD03two strains of Erlang mountain chicken. Besides the expression of RBP4in Roman egg shell powder was not highter than in SD02and SD03strains. In SD02strain, except that heart, liver, ovaries, pituitary and hypothalamus had the highest expression level at32week, others had no differences. In SD03strain, heart had the highest expression level at45week, liver、 pituitary and hypothalamus had the highest expression level at32week, others had no differences. In Roman egg shell powder, heart had the highest expression level at45week, pituitary and hypothalamus had the highest expression level at32week, others had no differences.Three mutation sites named M(T303721C)、N(C301334G)、P(T301387C), which were all samesense mutations were found in the exon2and4of RBP4. There were significant differences (P<0.05) for the weight at first egg, and egg shell strength(p<0.01) inM、N site. Genetype CC and GG had heavier the weight at first egg than genetype CG, genetype CG and GG had stronger egg shell strength than genetype CC. For site P, also had significant differences (P<0.05) for egg shell strength, haugh unit and albumen height. Genetype TT had stronger egg shell strength than genetype CT, genetype CT had more larger Haugh Unit and albumen heigh than genetype TT. So we can use RBP4polymorphism information to choose SD02and SD03of Erlang mountain chicken according to characters like the weight at first egg, shell strength, protein height and haugh unit. But the characters of the total number of eggs, age at first egg were still needed further validation.