Delayed Implantation

延迟着床

• 批准号: RGPIN-2018-05767
• 负责人: Murphy, Bruce
• 金额: $ 8.01万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=746067
• 关键词: Delayed; Implantation

The long-term objective of this research program is to determine the characteristics and regulation of a mammalian reproductive strategy known as embryonic diapause. Also known as delayed implantation, diapause is a trait found in 130 or more species of mammals, whereby which the embryo undergoes reversible developmental arrest at the blastocyst stage, to be later reactivated to implant in the uterus. This strategy uncouples mating from parturition and allows both to occur when conditions are most favorable for reproductive success and offspring survival. We propose to continue studies comparing obligate and facultative diapause by comparing carnivore and rodent models, with focus on changes in the embryo and on regulation of developmental arrest by the endometrium. The first short-term objective is to determine the gene expression patterns that characterize both the entry of the morula stage embryo into the blastocyst in diapause, and the exit of the blastocyst from diapause during the renaissance of development. This will be achieved by single cell transcriptome analysis of the two compartments of the blastocyst, the inner cell mass and the trophectoderm, followed by validation by transcript and protein analysis. The second objective is to determine the uterine (endometrial) mechanisms and pathways that regulate the entry and exit from diapause, again by transcriptome sequencing, followed by proteomic validation. The third objective is to test candidate secretory factors derived from Objectives 1 and 2 with embryos in vitro to establish their authenticity as regulators of diapause. In this objective, targets from the first objective will be explored in rodent embryos in vitro by pharmacological inhibition of intracellular pathways, and secondly, by using inhibitory RNA and overexpression strategies to manipulate gene expression. Embryos will be incubated with protein and other factors of uterine provenance. These factors, along with pharmacological agents and genomic tools that prove effective in inducing or maintaining diapause in rodent embryos will then be explored to determine their potential for inducing diapause in cattle, a species where the trait does not naturally occur. Bovine blastocysts in vitro will be employed and the endpoint will be the capacity for developmental arrest and consequent reactivation. Among multiple impacts of the study will be further discovery of the mechanisms that regulate diapause, potentially allowing for intervention to increase reproduction in endangered species that display diapause. If diapause can be induced in the bovine embryo, it opens the door to embryo preservation without freezing and its associated cellular damage.

这项研究计划的长期目标是确定被称为胚胎滞育的哺乳动物生殖策略的特征和调节。滞育也被称为延迟着床，滞育是在130种或更多种哺乳动物中发现的一种特征，胚胎在囊胚阶段经历可逆的发育停滞，随后被重新激活以植入子宫。这种策略将交配与分娩分开，并允许在最有利于繁殖成功和后代生存的条件下进行交配。我们建议通过比较食肉动物和啮齿动物模型来继续研究专性和兼性滞育，重点研究胚胎的变化和子宫内膜对发育停滞的调节。第一个短期目标是确定桑葚胚在滞育阶段进入囊胚的基因表达模式，以及发育复兴期间囊胚从滞育阶段退出的基因表达模式。这将通过对囊胚的两个区室，内细胞群和滋养外胚层的单细胞转录组分析来实现，然后通过转录和蛋白质分析进行验证。第二个目的是确定子宫（子宫内膜）调节进入和退出滞育的机制和途径，再次通过转录组测序，然后进行蛋白质组学验证。第三个目标是用体外胚胎测试目标1和目标2衍生的候选分泌因子，以确定它们作为滞育调节剂的真实性。在这个目标中，第一个目标将通过药物抑制细胞内通路在体外啮齿动物胚胎中探索，其次，通过使用抑制性RNA和过表达策略来操纵基因表达。胚胎将与子宫来源的蛋白质和其他因素一起孵育。这些因素，以及证明在诱导或维持啮齿动物胚胎滞育方面有效的药理学制剂和基因组工具，将被探索，以确定它们在牛中诱导滞育的潜力，牛是一个不会自然发生这种特性的物种。体外培养的牛囊胚将被使用，终点将是发育停止和随后的再激活的能力。在这项研究的多重影响中，将进一步发现调节滞育的机制，可能允许干预以增加显示滞育的濒危物种的繁殖。如果能在牛胚胎中诱导滞育，就为不冷冻保存胚胎及其相关的细胞损伤打开了大门。