The Polymorphism In5’-UTR Of PRL Gene And Its Association With Important Economic Traits In Geese

Prolactin (PRL) can inhibit the growth and development of follicles and adjusts thebroodiness, incubate and other maternal line of femalebird. The PRL gene can regulate thelevel of the PRL. This study was to analyze the polymorphism in5’-UTR of PRL gene andits association with important economic traits in geese.6goose populations, Rhine,Landaise, Roman, Yangzhou, Yan and F1population (Wanchuan) of Wanxi×Sichuangoose, were selected. Genomic DNA was extracted from blood of all geese. The fragmentcontained5’-UTR and part sequence of promoter rgion in PRL gene (PRL268) was clonedand sequencing. PRL268functions were investigated using structure prediction, SNPdetection, dual reporter gene assay, as well as its association with important economictraits in geese. The results showed that:(1) The means of DNA bending index in1to13bp,33to53bp, and61to70bpregions of the PRL268were33.99±5.88,51.74±3.81and52.17±3.96, respectively,while that in84to113bp region was18.05±6.06. There were the crest at120bp (45.88)and the stretching peak in145to163bp, which showed that these regions may havefunctional specificity. The transcription factor binding sites in the PRL268predicted wereTBP、NF-1、NF-E2、TATA-box、Pit-1、PR、Sp1、AP-1、CAC-binding_pro. Becauseof the characteristics of DNA-loop, some factor binding sites were neared each other.(2) T�'G mutation at10bp (T-10G, PRL268T/G) from CDS start point of5’-UTR inPRL268. The PRL268G gene frequencies were more than0.90in Rhine, Roman andLandaise,0.1563in Yangzhou,0.3517in Wanchuan, and0.5566in Yan.(3) The promoter effects of PRL268T/G were tested using dual reporter gene assay.The results showed that the ratio of renilla to firefly fluorescence intensity of PRL268Gincreased26.14%(p<0.01) than that of PRL268T, which indicated that the promoterefficiency was improved when T replaced with G at T-10G. site.(4) According to the gene frequency distribution and the goose egg yield levels, ThePRL268G was dominant gene in Rhin, Landes and Roman, while PRL268G in Yangzhou.The results indicated significantly association of PRL268G gene distribution with gooseegg yield levels.(5) The difference among carcass traits of different genotypes in Wanchuan showedthat the body weight and chest-leg muscle ratio of GG genotype were significantly greaterthan that of TT genotype.