Evaluation The Reproductive Performance Of Porcine KISS1 And FSHR Transgenic Mice

Reproduction is one of the important economic character. The low reproduction capacity is one of the reasons which limits the development of modern animal husbandry. Follicle stimulating hormone receptor (Follicle Stimulating Hormone Receptor, FSHR) and KISS1 genes play significant roles in litter size. Follicle stimulating hormone (Follicle Stimulating Hormone, FSH) plays vital role in promoting the gonadal development and maintaining reproductive function. FSHR is the receptor of FSH that distributes in the surface of cell membrane, and mediates the physiological regulation of FSH. KISS1 is an important regulatory factor inducing gonadotropin releasing hormone (Gonadotropin releasing hormone, GnRH) secretion and the central node in the gonadal axis system. Kisspeptins which are encoded by the KISS1 gene, can directly regulate the pulsatile secretion of gonadotropins, luteinizing hormone (Luteinizing hormone, LH) and FSH. LH and FSH stimulate the maturation of the gonads and regulate the function of the reproduction. KISS1 and its receptor gene G protein-coupled receptor 54 (G protein-coupled Receptor 54, GPR54) play key roles in the onset of puberty.In our previous studies, porcines FSHR and KISS1 gene transgenic(Transgenic, TG) mice were generated by constructing vector pCaMKIIα-KISS1 and AMH-pFSHR which were microinjected into mouse zygotes. The AMH-pFSHR and pCaMKIIα-KISS1 were specific expressed in the mouse ovarian granulosa cells and hypothalamus respectively. The positive rate of Fl-F5 generation TG mice, the expression of porcines FSHR and KISS1 genes and the effect of reproductive performance on female mice were checked. The main results are as follows,1. Porcines FSHR TG mice:The average litter size of F1-F5 generation TG mice were higher than wild type (Wild Type, WT) mice. The average litter size of F1 and F3 generations of TG mice were significantly higher than WT mice (P<0.05). Porcine FSHR (pFSHR) expression was detected in ovary of TG mice by RT-PCR and Quantitative real-time PCR, but not in heart, liver, spleen, kidney, uterus and hypothalamus. Mouse FSHR (mFSHR) gene detected in ovary of TG and WT mice. Western blot analysis showed that Porcine FSHR protein was expressed in ovaryof TG mice. There was no significant difference between TG and WT mice, which is resonable and agree with the result of Quantitative real-time PCR. The concentration of FSH, LH, estradiol and progesterone in serum that play the important roles in the repreoductive system were tested by ELISA when mice in diestrus. ELISA results indicated that these hormone have no significant differences in TG and WT mice(P>0.05). TG and WT females were mated with WT male respectively, then littler size, parity, farrowing interval, birthday were recorded. Reproduction data revealed that litter size increased with age first and then decreased. At the same age, little size of TG mice was higher compared to WT mice, and peaked in the 220 days of age (P<0.05).The farrowing interval of TG mice was shorter (P<0.05).2. Porcines KISS1 TG mice:The average litter size of F1-F5 generation TG mice were higher than WT mice. The average litter size of F1 and F2 generations of TG mice were significantly higher than WT mice (P<0.01 and P<0.05 respectively). Porcine KISS1 (pKISS1) expression was detected in hypothalamus of TG mice by RT-PCR and Quantitative real-time PCR, but heart, liver, spleen, kidney, uterus and ovary were not found. Mouse KISSl (mKISSl) gene detected in hypothalamus and ovary of TG and WT mice. Western blot analysis showed that porcine kisspeptin were expressed in hypothalamus. There was no significant difference between TG and WT mice, which is resonable and agree with the result of Quantitative real-time PCR. ELISA results indicated that the concentration of FSH and estradiol hormones of F4 generation TG mice were higher than WT mice (P<0.05). Reproduction data revealed that litter size of TG mice was higher compared to WT mice, and peaked in the 200 days of age.The farrowing interval of TG mice was shorter. Offspring mice of F4 porcines KISS1 TG mice initiate puberty onset earlier than WT mice, and ovary weight increased significantly(P<0.05)...