Uterine Vascular Remodeling during Pregnancy

描述（由申请人提供）：我们的实验室最近发现了一种新的小鼠g蛋白偶联受体（GPCR），该受体在胚胎植入后的蜕胞间室中上调（7倍）。RT-PCR和原位杂交显示，这种新型GPCR在时间和空间上局限于妊娠期间子宫间质室的表达模式，在其他组织/器官中不表达。使用人脱个体化基质细胞的研究表明，在人脱个体化过程中表达了一个功能性的对应物。因此，拟议的研究可能会对人类怀孕产生影响。同样，肾素（一种通过血管紧张素原的蛋白水解裂解产生活性血流动力学肽的酶）在妊娠早期在子宫内膜中被上调。我们的假设是，孤立的GPCR在正常妊娠的功能上是必需的，并且这种新的受体在母胚界面介导血管紧张素-(1-7)诱导的血管舒张。在Specific Aim 1中，我们建议在插入诱变研究中证明受体的功能需求，其中cre重组酶插入受体基因位点。特别的重点将给予子宫血管动力学和前列腺素的生产在妊娠早期。生成GPCR-cre小鼠系的一个重要方面是，由于该受体对子宫脱个体化的表达受到限制，该小鼠可以在未来的实验中作为急需的研究工具，使用Cre/LoxP技术研究其他被认为对子宫脱个体化很重要的基因。在特异性目标2中，我们将测试GPCR启动子驱动转基因表达的功能。该研究项目的成功完成将在受体信号传导领域有广泛的应用，并将促进我们对母胚相互作用的理解。

DESCRIPTION (provided by applicant): Our laboratory recently identified a novel murine G-protein coupled receptor (GPCR) that becomes up- regulated (7-fold) in the decidualizing stromal compartment in response to the implanting embryo. RT-PCR and in situ hybridization reveal that the novel GPCR is temporally and spatially restricted in its expression pattern to the stromal compartment of the uterus during pregnancy and is not expressed in other tissues/organs. Studies using human decidualized stromal cells suggest that a functional counterpart is expressed during human decidualization. The proposed studies will therefore have likely implications for human pregnancy. Likewise, it was established that renin, an enzyme that generates active hemodynamic peptides through proteolytic cleavage of angiotensinogen, is up-regulated in the endometrium during early gestation. Our hypothesis is that the orphaned GPCR is functionally required for normal pregnancy, and that this novel receptor serves to mediate angiotensin-(1-7)-induced vasodilation at the maternal-embryo interface. In Specific Aim 1 we propose to demonstrate the functional requirement of the receptor in insertional mutagenesis studies in which cre recombinase is inserted into the receptor gene locus. Particular focus will be given to uterine vascular dynamics and prostaglandin production during early pregnancy. One important aspect of generating the GPCR-cre mouse line is that, due to the restricted expression of the receptor to the decidualizing uterus, the mouse can be used in future experiments as a much needed research tool to study other genes thought to be important for uterine decidualization using Cre/LoxP technology. In Specific Aim 2, we will test the functionality of the GPCR promoter to drive transgene expression. Findings derived from the successful completion of this research project will have broad application to the field of receptor signaling and will advance our understanding of maternal-embryo interactions.