Are sperm-borne small RNAs important?

描述（申请人提供）：众所周知，小鼠和人类精子在受精过程中都携带大量的信使rna和小的非编码rna进入卵子。这些父系rna对受精和早期胚胎发育至关重要吗？如果是这样的话，这些精子携带的RNA分子进入卵子细胞质后会做什么呢？这些基本问题仍然没有答案，因为这些RNA分子隐藏在高度致密的精子染色质深处。因此，在不破坏父系DNA的情况下，这些精子携带的RNA几乎是完全无法接近的。我们已经产生了两个条件敲除小鼠系，它们产生的精子缺乏miRNAs和/或内切sirna。我们将使用这些小的非编码RNA缺陷精子进行卵胞浆内单精子注射（ICSI），观察受精率和早期胚胎发育（Aim2）。这些小RNA缺陷精子中的RNA含量也将与正常野生型精子中的RNA含量进行比较（Aim1）。阴性结果表明，至少这两种精子携带的小非编码RNA物种对于受精和/或早期胚胎发育是不可或缺的。然而，如果发现这两个小RNA物种对受精和/或胚胎发育至关重要，那么就需要进行更彻底的研究

DESCRIPTION (provided by applicant): It is well known that both mouse and human sperm carry numerous messenger RNAs and small non-coding RNAs into eggs during fertilization. Are these paternal RNAs essential for fertilization and early embryonic development? If so, what do these sperm-borne RNA molecules do once inside the cytoplasm of the egg? Theses fundamental questions remain unanswered because these RNA molecules are hidden deeply inside the highly compacted sperm chromatin. Thus, these sperm- borne RNA species are almost totally inaccessible without disrupting paternal DNA. We have generated two conditional knockout mouse lines, which produce sperm lacking miRNAs and/or endo-siRNAs. We will use these small non-coding RNA- deficient sperm to perform intracytoplasmic sperm injection (ICSI) to observe the fertilization rate and early embryonic development (Aim2). The RNA contents in these small RNA-deficient sperm will also be defined in comparison to those in normal wild-type sperm (Aim1). A negative finding would suggest that at least these two sperm-borne small non-coding RNA species are dispensable for fertilization and/or early embryonic development. However, if these two small RNA species are found to be essential for fertilization and/or embryonic development, then a more thorough study is warranted because the paternal contribution to fertilization or even early embryonic development has been hypothesized for a long time and it represents one of the most fundamental questions about factors that are required for the beginning of a life. Therefore, this exploratory study fits the high risk, high reward philosophy of the R2 funding mechanism. PUBLIC HEALTH RELEVANCE: The study will test whether two of the sperm-;borne small RNA species are required for fertilization and early embryonic development. Data from this study will potentially lead to discoveries of novel factors that are responsble for infertility, spontaneous abortion and birth defects.