CONSEQUENCES OF MALE LH RECEPTOR GENE KNOCKOUT

描述：(申请人提供)我们最近成功地创建了 黄体生成素受体基因敲除(LHRKO)小鼠 同源DNA重组技术。LHR基因的靶向缺失 外显子1区域的启动子完全使该基因失活，这 结果在纯合子动物的性腺中未检测到LHR。LHR 空雄性不是致命性的，而是不育的，而它们的杂合子后代 看起来很正常。纯合子男性的外生殖器和内生殖器 严重不发达，精子发生在 精母细胞。这种表型被认为是由雄激素减少引起的。 无促黄体生成素刺激对睾丸间质细胞的影响 睾酮替代疗法，尽管睾丸有改善 形态和精子发生，没有恢复男性生育能力，为纯合子 雄性的精子数量和活动率都非常低。鉴于这一事实， 具有广泛的作用，由其在性腺和非性腺中的受体介导 精子和附睾中的功能性LHR等组织，以及初步的 从LHRKO男性获得的结果，我们假设黄体生成素的贡献 对精子发生的影响可能不仅仅是对间质细胞产生雄激素的作用 制作。拥有这一独特的LHRKO鼠标模型使我们能够选择性地 研究黄体生成素在生殖生物学中的关键作用。这项建议 研究旨在寻找LHRKO不孕不育的潜在原因 男性即使在雄激素替代治疗后也是如此。因此，这笔小小的赠款 应用程序将只关注已知的两个方面 精子发生和精子成熟，被列为两个特定的目标：1) 研究LHRKO对生精细胞的影响。2)确定 LHRKO对精子成熟的影响这些功能数据对于 美国将进一步研究促黄体生成素在男性生殖中的重要作用 生物化学和分子水平。人类因遗传缺陷造成的不孕不育 在LHR或LH-p亚基中越来越被认识，但没有天然的 可供研究的具有相应突变的发生动物模型。 因此，从这些LHRKO小鼠获得的数据不仅将推动我们的 了解促黄体生成素对正常男性有多重要 生殖生理学，但也将有助于开发更好的诊断 和治疗男性不育症的选择，反过来，发展出更多 有效和安全的男性避孕药。

DESCRIPTION: (Provided by the Applicant) We recently succeeded in creating mice with the luteinizing hormone receptor gene knockout (LHRKO) by a homologous DNA recombination technology. Targeting deletion of the LHR gene at the promoter to exon one region completely inactivated the gene, which resulted in no detectable LHR in the gonads of homozygous animals. The LHR null males are not lethal but sterile, while their heterozygous littermates appear to be normal. The external and internal genitalia of homozygous males were grossly underdeveloped and spermatogenesis was arrested at the spermatocytes. The phenotype is believed to be caused by decreased androgen influence in the absence of LH stimulation of testicular Leydig cells. Testosterone replacement therapy, in spite of improvement in testicular morphology and spermatogenesis, did not restore male fertility, as homozygous males have very low sperm numbers and motility. In view of the fact that LH has pervasive actions, mediated by its receptors in gonadal and nongonadal tissues such as functional LHR in sperm and epididymis and with preliminary results obtained from LHRKO males, we hypothesize that the contribution of LH to spermatogenesis may be more than just acts on Leydig cells for androgen production. Having this unique LHRKO mouse model enables us to selectively investigate the crucial roles of LH in reproductive biology. This proposed research is aimed at searching for potential causes of infertility in LHRKO males even after androgen replacement therapy. Therefore, this small grant application will only focus on two aspects that are known to be critical in spermatogenesis and sperm maturation, listed as two specific aims: 1) investigating the effect of LHRKO on spermatogenic cells. 2) determining the effect of LHRKO on sperm maturation. These functional data are essential for us to further investigate the vital role of LH in male reproduction at biochemical and molecular levels. Infertility in human due to genetic defects in LHR or LH-p subunit are increasingly recognized, but there are no naturally occurring animal models with the corresponding mutations available for study. Thus, the data obtained from these LHRKO mice will not only advance our understanding on how important the actions of LH are for normal male reproductive physiology but will also facilitate developing better diagnostic and therapeutic options for male infertility and, conversely, developing more effective and safer male contraceptive reagents.