Modification of the intracellular signaling machinery leading to the acquisition of sperm fertilizing ability

我的研究计划的主要目标是更好地了解精子获得与卵子相互作用并使卵子受精的能力的机制。 精子细胞内的生化机制在此过程中被修改。 有几种信号级联反应是由来自女性生殖道的不明确因素，卵子本身或排卵过程中随卵子释放的卵泡产物触发的。 我们确定了精子细胞内蛋白质，这些蛋白质被怀疑是精子受精能力激活的信号通路的一部分。 然而，这些酶的伴侣尚未确定。 因此，我们的目标之一是确定我们蛋白质的上游和下游因素，以便更好地了解精子发生了什么，使它们能够胜任精子。 此外，精子/卵子相互作用是高度特异性的现象。 除了极少数例外，一种动物的精子只能使同一物种的卵子受精。 来自两个配子的蛋白质都参与了这个识别过程。 我们鉴定并部分纯化了一种负责精子与卵子结合的精子蛋白。 当精子经历附睾成熟时，这种蛋白质被修饰，我们非常有兴趣确定这些修饰的性质。 此外，我们怀疑这种蛋白质也会随着精子获得其抗精子能力而受到影响。 因此，重要的是要确定这些修饰的性质，并了解它们如何影响这种蛋白质介导精子和卵子之间相互作用的能力。 在自然条件下，受精发生在雌性生殖道内，即输卵管内。 因此，精子在向卵子的内部运输过程中获得与卵子相互作用并使卵子受精的能力。 我的研究计划的一部分是确定子宫或输卵管如何使精子受精。 是通过精子和上皮细胞之间的直接细胞相互作用还是通过女性生殖道的分泌物？

The major objective of my research program is to better understand the mechanisms by which sperm acquire the ability to interact with and fertilize the egg.  Sperm intracellular biochemical machinery is modified during this process.  There are several signalling cascade that are triggered either by poorly defined factors from the female reproductive tract, by the egg itself, or by follicular products that are released with the egg during the ovulation process.  We identified sperm intracellular proteins that are suspected to be part of a signalling pathway activated as sperm become fertilization competent.  However, the partners of these enzymes have not been identified.  One of our goals is therefore to identify the factors upstream and downstream of our proteins in order to have a better idea of what is happening to sperm to make them competent at fertilizing.  Furthermore, sperm/egg interactions are highly specific phenomena.  With only rare exceptions, sperm from one animal specie can only fertilize an egg from the same specie.  Proteins from both gametes are involved in this recognition process.  We identified and partly purified one of the sperm proteins putatively responsible for the sperm binding to the egg.  As this protein is modified when sperm undergo epididymal maturation, we are greatly interested to identify the nature of these modifications.  In addition, we suspect that this protein is also affected as sperm acquires its fertilizing competence.  It is, therefore, important to determine the nature of these modifications and to understand how they affect the ability of this protein to mediate the interactions between sperm and egg.  Under natural conditions, fertilization occurs within the female genital tract, in the oviduct.  Therefore, sperm acquire its ability to interact with and fertilize the egg during its internal transit toward the egg.  A part of my research program is to determine how the uterus or oviducts render sperm fertilization competent.  Is it through direct cellular interactions between sperm and epithelial cells or through secretions from the female reproductive tract?