CONSEQUENCES OF MALE LH RECEPTOR GENE KNOCKOUT

男性 LH 受体基因敲除的后果

• 批准号: 6317900
• 负责人: ZHENMIN LEI
• 金额: $ 7.2万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-04-13 至 2003-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6317900
• 关键词: androgens; biological models; cell growth regulation; cell transplantation; epididymis; fertility; gene deletion mutation; gene induction /repression; gene targeting; genetically modified animals; hormone therapy; laboratory mouse; luteinizing hormone; male; mixed tissue /cell culture; morphology; receptor expression; southern blotting; sperm; spermatogenesis

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.

描述：（由申请人提供）我们最近成功创建了 用黄体生成激素受体基因基因敲除（LHRKO）的小鼠 同源DNA重组技术。靶向LHR基因的删除 向外显子一个区域的启动子完全灭活了该基因，该基因 在纯合动物的性腺中未检测到LHR。 LHR 无效的男性不是致命的，而是无菌的，而他们的杂合窝窝夫人 似乎正常。纯合雄性的外部和内部生殖器 被严重发育不良，精子发生在 精子细胞。表型被认为是由雄激素降低引起的 在没有LH刺激睾丸Leydig细胞的情况下的影响。 睾丸激素替代疗法，尽管睾丸有所改善 形态学和精子发生，没有恢复男性生育能力，作为纯合子 雄性的精子数量和运动性非常低。鉴于LH 其受体在性腺和nongonadal中具有普遍的作用 组织，例如精子中的功能性LHR，并具有初步 从LHRKO男性获得的结果，我们假设LH的贡献 对于精子发生，可能不仅仅是作用于雄激素的leydig细胞 生产。拥有这种独特的LHRKO鼠标模型使我们能够选择性地 研究LH在生殖生物学中的关键作用。这提出了 研究旨在寻找LHRKO中不育的潜在原因 即使在雄激素替代疗法之后，男性也是如此。因此，这个小的赠款 应用只专注于已知至关重要的两个方面 精子发生和精子成熟，被列为两个特定目的：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 我们进一步研究LH在男性繁殖中的重要作用 生化和分子水平。由于遗传缺陷，人类不孕症 在LHR或LH-P亚基中，越来越多地认识到 发生具有相应突变的动物模型。 因此，从这些LHRKO小鼠获得的数据不仅会推动我们的 了解LH对正常男性的行为的重要性 生殖生理学，但也将有助于开发更好的诊断 和男性不育的治疗选择，相反，发展更多 有效，更安全的男性避孕试剂。