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Molecular basis of cryptorchidism-induced infertility

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Science china(Life sciences) 2010年第11期53卷 1274-1283页

作者： liu YiXun & LI XiXia State key laboratory of reproductive biology, institute of zoology, chinese academy of sciences, beijing 100101, china 1. State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Artificial cryptorchidism or local testicular heat treatment can induce reversible oligospermia or azoospermia in monkeys and rats via germ cell apoptosis. Local warming of monkey testes in water at 43°C for 2 consecutive days (30 min per day) decreased the number of sperm in the semen by up to 80% on d 28, and the effect was completely reversed on d 144. Germ cells rely heavily on Sertoli cells for structural and nutritional support. Specialized junctions that play a pivotal role in spermatogenesis occur at sites of Sertoli-Sertoli and Sertoli-germ cell contact in the seminiferous epithelium. We demonstrated that expression of tight junction (TJ)-associated molecules, such as occludin and zonula occludens-1 (ZO-1), were greatly reduced 24–48 h after heat treatment, while the permeability of the blood-testis barrier (BTB) was simultaneously increased, but recovered 10 d later. These results indicate a reversible disruption of the BTB associated with transient inductions of transforming growth factor (TGF) β2 and β3 expression, p38 mitogen-activated protein kinase and extracellular signal-regulated kinase activation, and concomitant loss of occludin and ZO-1. This suggests that expression of TJ-associated molecules and the BTB was reversibly perturbed by mild testicular hyperthermia, and that the heat-induced induction of TGF-β might be involved in downregulating TJ-associated proteins, leading to cell junction reduction. This review discusses the changes in total gene expression patterns after experimental cryptorchidism in adult mouse testes, and the cloning of several novel, physiologically significant spermatogenesis-specific genes.

关键词： cryptorchidism spermatogenesis apoptosis heat stress Sertoli cells blood-testis barrier tight junction

Follicular growth,differentiation and atresia

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chinese Science Bulletin 2003年第17期48卷 1786-1790页

作者： JIN Xuan & liu Yixun State key laboratory of reproductive Biololgy, institute of zoology, chinese academy of sciences, beijing 100080, china State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

Only limited numbers of primordial follicles in mammalian ovary grow and differentiate to reach the stage of dominate follicles and ovulate. 99% of the follicles in the ovary undergo atresia at various stages of development. Regulation of follicular growth, development and atresia is a complex process and involves interactions between endocrine factors and intraovarian regulators. This review summa-rized:ⅰ) FSH may not be a survival factor in regulating slow-growing preantral follicles. Some locally produced growth factors, activin and orphan receptors might play a more important role at this stage. ⅱ) Estrogen, activin/ inhibin and follistatin coordinate with FSH to regulate and control follicle differentiation. ⅲ) There are two types of follicular atresia induced by apoptosis which originates from GC or oocyte, respectively. Early translation of tPA mRNA into tPA protein in oocyte may be associated with oocyte apoptosis.

关键词：哺乳动物原始卵泡卵泡生长粒状细胞细胞分化

Role of ubiquitination in meiotic recombination repair

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Science china(Life sciences) 2010年第4期53卷 447-454页

作者： CUI Li & LI Wei State key laboratory of reproductive biology, institute of zoology, chinese academy of sciences, beijing 100101, china 1. State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Programmed and unprogrammed double-strand breaks (DSBs) often arise from such physiological requirements as meiotic recombination, and exogenous insults, such as ionizing radiation (IR). Due to deleterious impacts on genome stability, DSBs must be appropriately processed and repaired in a regulatory manner. Recent investigations have indicated that ubiquitination is a critical factor in DNA damage response and meiotic recombination repair. This review summarizes the effects of proteins and complexes associated with ubiquitination with regard to homologous recombination (HR)-dependent DSB repair.

关键词： ubiquitin meiosis homologous recombination DNA double-strand breaks

Progress in interspecies cloning of mammals

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Progress in Natural Science:Materials International 2004年第1期14卷 2-9页

作者： WEN Duancheng, BI Chunming and CHEN Dayuan(State key laboratory of reproductive biology, institute of zoology, chinese academy of sciences, beijing 100080, china) chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China

Interspecies mammalian cloning can be achieved by application of two key techniques, i.e. the technique of interspecies nuclear transfer and the technique of interspecies pregnancy. The general principles, problems and possible solutions, as well as the recent advances of interspecies mammalian cloning have been summarized in this review.

关键词： interspecies cloning interspecies nuclear transfer interspecies pregnancy mammals

Comparative study on the effect of integrin αvβ3 on secretion of matrix metalloproteinases in human normal and carcinoma trophoblasts

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Progress in Natural Science:Materials International 2005年第11期15卷 982-987页

作者： BAI Suxia, FU Yayuan, KONG Gang and WANG Yanling (State key laboratory of reproductive biology, institute of zoology, chinese academy of sciences, beijing 100080, china The Second Hospital of chinese Medicine College, Shenyang 110003, china) State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. The Second Hospital of chinese Medicine College Shenyang 110003 China

The invasion of cytotrophoblast cells into the maternal endometrium during embryonic implantation is very similar to the metastasis of carcinoma cells. However, the significant difference is that the former is a highly controlled process. In this report, the effects of integnn αvβ3 on the secretion of matrix metalloproteinase (MMP) were compared between normal cytotrophoblast cells and chorio-carcinoma cells by RT-PCR, gelatin zymography and immunocytochemistry. The results reveal that both normal cytotrophobiast cells and choriocarcinoma cells can express integrin αvβ3. The secretion of MMPs in normal cytotrophoblast cells is up-regulated by anti-αvβ3 antibody, whereas, decreased in choriocarcmoma cells. It was suggested that αvβ3 can modulate the expression of MMPs in trophoblasts, and this action is carried out through distinct mechanisms in normal and carcinoma cytotrophoblast cells.

关键词： cytotrophoblast cells choriocarcinoma cells integrfn αvβ3 matrix metalloproteinase.

The Fate of Mitochondria in Ibex-hirus Reconstructed Early Embryos

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 371-374页

作者： Yan JIANG, Shu-Zhen liu, Yan-Ling ZHANG, Man-Xi JIANG, Qing-Yuan SUN, and Da-Yuan CHEN* State key laboratory of reproductive biology, institute of zoology, the chinese academy of sciences, beijing 100080, china State key laboratory of reproductive biology Institute of Zoology the Chinese Academy of Sciences Beijing 100080 China

Inter-species nuclear transfer could be used to preserve North Goat (Capra ibex), an endan- gered species. We established the culture conditions for ibex-hirus reconstructed embryos and optimized the method for DNA extractions of a single cell and early cloned embryo. By using mitochondria-specific probes of ibex and hirus respectively we found that mitochondria of donor cells can co-exist with recipients in 1-cell and 2-cell stages of the reconstructed embryos but not in the following developmental stages.

关键词： Capra ibex cloned embryos nuclear transfer mitochondria PCR

Expression of gelatinases and tissue inhibitors of metallo-proteinases in the rhesus monkey(Macaca mulatta) corpus luteum

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chinese Science Bulletin 2001年第15期46卷 1292-1296页

作者： LI Qinglei, WANG Hongmei, SHAO Longjiang, YU Xiaoguang, Nl Jiang & ZHU Cheng1. State key laboratory of reproductive biology, institute of zoology, chinese academy of sciences, beijing 100080, china 2. laboratory of reproductive Endocrinology, Harbin Medical University, Harbin 150001, china State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing China laboratory of reproductive Endocrinology Harbin Medical University Harbin China

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are believed to play important roles in the formation and regression of corpus luteum (CL). This study is to investigate the expression of gelatinases (MMP-2, -9) and TIMPs in the rhesus monkey CL in both early and late luteal phases and during the early stages of pregnancy. Ovaries were collected from regularly cycling rhesus monkey at D5 and D15 following ovulation and at D12, D18 and D26 of pregnancy. In situ hybridization revealed that in the CL MMP-2 niRNA was expressed during both formation and regression, while MMP-9 mRNA was mainly localized in the late luteal phase. Reduction of MMP-2, -9 transcripts in the CL was observed during pregnancy. MMP-2 mRNA in the CL reduced to an undetectable level at D26 of pregnancy. TIMP-1 mRNA was highly expressed in the CL in both early and late luteal phases and persisted throughout the early stages of pregnancy. Strong signal for TIMP-2 mRNA was also detected in both luteal phases, and the

关键词： matrix metalloproteinases tissue inhibitors of metallo-proteinases gelatinases macaca mulatta corpus luteum.

Replacement of inner cell mass in mouse

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chinese Science Bulletin 2003年第13期48卷 1347-1351页

作者： BI Chunming, WEN Duancheng, XU Ying, SUN Qingyuan & CHEN Dayuan State key laboratory of reproductive biology, institute of zoology,chinese academy of sciences, beijing 100080, china Correspondence should be addressed to Chen Dayuan(e-mail: chendy@ ***) State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences China

The intra- or inter-strain reconstitutedblastocysts were produced by replacing the inner cell mass of Kunming mouse blastocysts with that of Kunming orC57BL/6 mouse strain blastocysts. A total of 192 intra-strain reconstituted blastocysts were transferred into 17pseudopregnant Kunming mice, and 2 reconstituted embryos were developed into term; while 115 inter-strain reconstituted blastocysts were produced, analysis of thereconstituted blastocysts showed that the morphology andcytoskeleton srtucture of the blastocysts were not differentfrom those of normal blastocysts, however, no viableoffspring was obtained after embryo transfer for these inter-strain reconstituted blastocysts. The resultsdemonstrated that the intra-strain reconstituted blastocystscould normally develop into term, whereas the inter-strain reconstituted blastocysts possessed less developmental potential as the intra-strain reconstituted blastocysts. Thisstudy may give light to solve the problem of low implantation rate and placenta abnormality in mammal cloning.

关键词：内细胞群细胞替代老鼠再生胚泡形态学克隆技术

Effects of MEK inhibitor U0126 on meiotic progression in mouse oocytes: microtuble organization, asymmetric division and metaphase Ⅱ arrest

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Cell Research 2003年第5期13卷 375-383页

作者： CHAO TONG, HENG YU FAN, DA YUAN CHEN, XIANG FEN SONG, HEIDE SCHATTEN, QING YUAN SUNI 1 State key laboratory of reproductive biology, institute of zoology, chinese academy of sciences, beijing 100080, china. 2 Department of Veterinary Pathobiology, University of Missouri-Columbia, MO 65211, USA 1State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. E-mail: sunqy@*** 1State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. E-mail: sunqy@*** 1State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. E-mail: sunqy@*** 1State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. E-mail: sunqy@*** 2Department of Veterinary Pathobiology University of Missouri-Columbia MO 65211 USA. 1State key laboratory of reproductive biology Institute of Zoology Chinese Academy of Sciences Beijing 100080 China. E-mail: sunqy@***

In this study we used U0126, a potent and specific inhibitor of MEK, to study the roles of MEK/ERK/p90rsk signaling pathway in the meiotic cell cycle of mouse oocytes. The phosphorylation of MAP kinase and p90rsk in the oocytes treated with 1.5 μM U0126 was the same as that in oocytes cultured in drug-free medium. With 1.5 μM U0126 treatment, the spindles appeared normal as they formed in oocytes, but failed to maintain its structure. Instead, the spindle lost one pole or elongated extraordinarily. After further culture, some oocytes extruded gigantic polar bodies （>30 μm） that later divided into two small ones. Some oocytes underwent symmetric division and produced two equal-size daughter cells in which normal spindles formed. In oocytes with different division patterns, MAP kinase was normally phosphorylated. When the concentration of U0126 was increased to 15 mM, the phosphorylation of both MAPK and p90rsk were inhibited, while symmetric division was decreased. When incubating in medium c

关键词： kinases signal transduction oocyte development fertilization meiosis.