FUNCTION OF UTERINE CALCITONIN DURING IMPLANTATION

着床期间子宫降钙素的功能

• 批准号: 6387818
• 负责人: Indrani C Bagchi
• 金额: $ 26.46万
• 依托单位: UNIVERSITY OF ILLINOIS AT URBANA-CHAMPAIGN
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-30 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6387818
• 关键词: antisense nucleic acid; biological signal transduction; cadherins; calcitonin; cell cell interaction; developmental genetics; early embryonic stage; embryo /fetus transplantation; embryo implantation; endometrium; expression cloning; female; gene expression; hormone receptor; hormone regulation /control mechanism; human tissue; immunocytochemistry; in situ hybridization; laboratory rat; mammalian embryology; menstrual cycle; pregnancy; receptor expression; second messengers; tissue /cell culture

The long-term objective of this research proposal is to explore the molecular basis of the regulation of embryonic implantation by calcitonin (CT), a peptide hormone that regulates calcium homeostasis. The expression of CT is induced in the glandular epithelium of rat uterus in the preimplantation phase of gestation and is switched off once implantation is completed. CT expression in human endometrium is restricted to the mid- secretory phase (days 19-24) of the menstrual cycle, with closely overlaps with the putative window of implantation. These findings suggest that CT may function as an important regulatory signal in the uterus during implantation. The specific aims of this proposal are: 1. To determine the functional event(s) regulated by CT during implantation. Administration of antisense oligodeoxynucleotides (ODNs), targeted against CT mRNA, into the preimplantation phase uterus results in marked suppression of the steady-state level of uterine CT mRNA. This intervention is also accompanied by a severe reduction in the number of implanted embryos. These results suggest that the impairment of implantation could be a direct phenotypic consequence of the blockade of CT gene expression by the antisense ODN. The effect of antisense ODN-induced CT deficiency on (a) uterine receptivity and (b) the ability of the embryo to implant will be examined by embryo transfer experiments. 2. To elucidate the signal transduction pathway(s) of CT in transformed human endometrial cell line Ishikawa and in primary cultures of human endometrial epithelial cells. CT acts on target cells through specific cell surface receptors. The expression of the CT receptor is also markedly elevated in the preimplantation endometrial epithelium. The second messenger pathways that are activated by CT via its receptor will be investigated in Ishikawa and primary cultures of endometrial epithelial cells. 3. To identify the genes that mediate the cellular actions of CT. CT stimulates the expression of c-fos mRNA while it inhibits the expression of osteopontin mRNA in human endometrial cells. To further understand how CT influences the embryo-uterine interactions, additional genes whose expression in the target cells is modulated in response to this hormone will be identified by subtractive cloning and their spatio-temporal expression in human endometrium during the menstrual cycle will be determine. The proposed study will provide valuable insights into the molecular mechanisms underlying the chain of events that link the transient expression of CT in the uterine glands to the control of embryo-endometrial interactions during implantation.

该研究建议的长期目标是探索降钙素（CT）调节胚胎植入的分子基础，降钙素（CT）是一种调节钙稳态的肽激素。 在妊娠前植入阶段，在大鼠子宫的腺上皮中诱导CT的表达，并在植入完成后关闭。 人子宫内膜中的CT表达仅限于月经周期的分泌阶段（第19-24天），与推定的植入窗口紧密重叠。 这些发现表明，CT在植入过程中可能是子宫中重要的调节信号。 该提案的具体目的是：1。确定植入过程中CT调节的功能事件。 针对CT mRNA的反义寡脱氧核苷酸（ODN）施用到植入前的子宫中会导致明显抑制子宫CT mRNA的稳态水平。 这种干预还伴随着植入的胚胎数量的严重减少。 这些结果表明，植入的损害可能是反义ODN阻断CT基因表达的直接表型结果。 反义ODN诱导的CT缺乏对（a）子宫接受性的影响以及（b）胚胎植入物的能力将通过胚胎转移实验来检查。 2。阐明在转化的人子宫内膜细胞系Ishikawa和人子宫内膜上皮细胞的原代培养物中CT的信号转导途径。 CT通过特定的细胞表面受体作用于靶细胞。 在植入前子宫内膜上皮细胞中，CT受体的表达也显着升高。 CT通过其受体激活的第二通道途径将在Ishikawa和子宫内膜上皮细胞的一级培养中进行研究。 3。确定介导CT细胞作用的基因。 CT刺激C-FOS mRNA的表达，同时它抑制人子宫内膜细胞中骨桥蛋白mRNA的表达。 为了进一步了解CT如何影响胚胎 - 局部相互作用，将通过减法克隆来鉴定其在靶细胞中的表达对这种激素进行调节的其他基因，并确定其在月经周期中人类子宫内膜中的时空表达。 拟议的研究将提供对事件链的分子机制的有价值的见解，这些事件链将子宫腺中CT的瞬时表达与植入过程中胚胎 - 内膜相互作用的控制联系起来。