In all mammalian species, progesterone is essential in the preparation for and maintenance of pregnancy, if it occurs. Progesterone primes the endometrium for possible implantation and inhibits uterine contraction until birth. Aldo‐keto reductases (AKRs) belong to a superfamily of NADPH‐dependent reductases that act on a wide range of substrates, including simple carbohydrates, steroid hormones, and endogenous prostaglandins. 20‐alpha hydroxysteroid dehydrogenase (20α‐HSD; EC.1.1.1.149) enzyme belongs to the family of aldo‐keto reductases. 20α‐HSD predominantly converts progesterone into its biologically inactive form 20α‐hydroxyprogesterone (20α‐OHP), and plays a crucial role in the termination of pregnancy and initiation of parturition. We have been reporting on the molecular characterizations of placental and ovarian 20α‐HSD in the bovine, pig, deer and monkey.In this study, to understand the fundamental function of monkey 20α‐HSD, we created transgenic mice expressing EGFP gene under monkey 20α‐HSD promoter. The EGFP protein was expressed in the placenta and ovary of tg mice during pregnancy. Now, we are trying to elucidate the function by PGF2α, Prolactin, Oxytocin. (Eun‐Bi Seo and Chae‐Won Park were supported by a scholarship from the BK21 Plus Program (31Z20130012928). the Ministry of Education, Science and Technology, korea)

The aldo‐keto reductase (AKR) superfamily are monomeric oxidoreductases that catalyze the NADP(H)‐dependent reduction of a wide variety of substrates, including seroids, prostaglandins, bile acids, carbohydrates, and xenobiotics. A group of AKRs known as hydroxydteroid dehydrogenase (HSDs) play a pivotal role in the modulation and regulation of steroid hormones, such as androgen, estrogens, and progestins, and are thus considered important targets for drug design. Thus, to gain further insights into the expression and localization of 20 HSD in the porcine ovary and placenta during early pregnancy, we analyzed the mRNA and protein expressions and immunohistochemistry. The expression of mRNA and protein was particularly strong in the ovary on day 31 of pregnancy. We also reported that 20[alpha]‐HSD was localized in the villus of trophoblast and endometrium glands during early pregnancy. Further studies are needed to determine the functional significance of porcine 20[alpha]‐HSD during pregnancy.

Human protein C (hPC) is a regulator of homeostasis, suggesting its potential use as a therapy for many disease states. Protein C is a zymogen of a serine protease that is activated by thrombin. Protein C, also known as autoprothrombin ¢òA and blood coagulation factor ¢û¢õ, is a zymogenic (inactive) protein, the activated form of which plays an important role in regulating blood clotting, inflammation, cell death and maintaining the permeability of blood vessel walls in humans and other animals. hPC is a 62 KD disulfide‐linked heterodimer consisting of a 21 KD light chain and a 41 KD heavy chain which circulates as an inactive zymogen in plasma.In this study, we focus on generation of hPC transgenic mice. hPC transgenic mice were produced by using micro‐injection method. The hPC cDNA was cloned into pBC1 vector under goat beta‐casein promoter. One‐cell stage embryos microinjected were transferred to 24 recipient mice on day 1 of the estrus cycle. We screened 61 mice by the PCR. Four line transgenic mice were identified and confirmed expression of protein C gene in mammary gland and several organ. We also analyzed the expression of mRNA and protein through the northern blot and western blot in mammary gland of hPC transgenic mice. hPC was localized in the alveolar epithelial cell by immunohistochemistry. Now, we are collecting the milk from the 2 found lines.