Production Of BMPR-IB Transgenic Pigs

The fertility is an important trait in the pig industry. Pig breeders always aim to produce prolific pigs with higher litter size. However, the reproductive performance is controlled by multiple genes and affected by many other factors such as environment, nourishment and so on. Since the transgenic "giant mouse" was produced in 1982, scientists began to utilize the transgenic technology to improve production of pigs. In pace with the presence of Somatic Cell Nuclear Transfer(SCNT) technique, the "disease resistant-swine", "environment-friendly-swine", "fast-growth swine" and other transgenic porcine have been produced. In this study, somatic cell clone technique was used to produce the trans-BMP-RIB-gene pigs.The bone morphogenetic protein receptor IB (BMPR-IB) gene is the first major gene for fecundity identified in Booroola-Merino sheep, BMPR-IB gene is located on the region of porcine chromosome 8. The complete cDNA sequence of 3559 basepair with open reading frame(ORF) of 1509 basepair. In this study, we obtained the completed cDNA of BMPR-IB by using total RNA from brain and ovarian tissues, and performed the site directed mutagensis on BMPR-IB, that was intergrated into the recombined vector pEF-GFP. After the insertion of the Neo-gene, the eukaryotic expression vector, and pEF-BMPRIB-Neo was generated. This vector was transfected into the Large White fetal fibroblasts by using the liposome transfection. Positive cell lines were achieved after G418 screened, and these somatic cell lines were merged into porcine oocytes at Mâ…¡phase by microscopic injections. Electronic pulse was used to fuse and activate transgenic embryo. Transgenic embryos were then cultured in the chemical supplementary activation drops with Cytochalasin-B and 6-DMAP for 3-4 hours. Transgenic embryos at 2-4 cell phases were implanted into the bottom of fallopian tube under surgery, and then for the final production of transgenic pigs.This research was expected to get prolific transgenic pigs by genetically modified cloning technology in the shortest time, and improve survival rate number and piglets nest farrowing, thus producing prolific breeding pigs, and promoting the development of the pig industry.