Collaborative Research: The Roles of Sperm-Egg Interactions in Reproductive Isolation in Drosophila

这项研究将应用新的技术进步来研究一个悬而未决的生物学问题--受精过程中和受精后的精子-卵子相互作用如何影响生殖成功？传统上，精子的主要作用被视为“DNA货物”的运输工具。然而，最近的证据表明，精子可能在受精和早期发育中发挥更基本的作用。例如，在几乎所有被检查的病例中，包括人类和其他哺乳动物，整个精子细胞在受精时进入卵子。因此，卵子内的精子结构可能是受精的基本要素，这一点得到了果蝇突变体的存在的支持，这些突变体在卵子内的精子结构和随后的胚胎发育中都存在缺陷。卵子内精子之间的这种不亲和性可能代表了个体之间不育的一种未知机制。精卵不亲和性的研究将分三步进行：(1)测定同种交配的卵子内精子的三维结构，并与之进行比较；(2)不同物种交配的卵子内的三维精子结构。在(1)和(2)中收集的信息将用于详细分析精子-卵子相互作用改变后的健康后果。(3)将使用虚拟现实环境CAVE来确定3D精子结构，在其中将跟踪和比较精子在卵子内的3D投影。洞穴的使用代表了超级计算技术在复杂生物过程中的一种新应用。精子-卵子在受精过程中和受精后相互作用的普遍性质表明，这些发现将与包括濒危物种和人类在内的广泛动物的生殖生物学相关。

This research will apply new technological advances to the study of an outstanding biological question - how do sperm-egg interactions during and following fertilization affect reproductive success? The primary role of sperm has traditionally been viewed as a delivery vehicle for the "DNA cargo." However, recent evidence indicates that sperm may play a more fundamental role in fertilization and early development. For example, in almost all cases examined, including humans and other mammals, the entire sperm cell enters the egg at fertilization. Sperm structure within the egg may therefore be an essential element of fertilization, as supported by the existence of Drosophila mutants defective in both sperm structure within the egg and subsequent embryonic development. This incompatibility between sperm inside the egg may represent an unrecognized mechanism of sterility between individuals. Sperm-egg incompatibility will be studied in three steps using Drosophila: (1) the 3D structure of sperm inside eggs from matings of the same species will be determined and compared with, (2) the 3D sperm structures inside eggs from matings between different species. Information gathered in (1) and (2) will be used for a detailed analysis of the fitness consequences of altered sperm-egg interactions. (3) 3D sperm structure will be determined using the CAVE, a virtual reality environment, in which 3D projections of sperm inside eggs will be traced and compared. The use of the CAVE represents a novel application of super computing technology to complex biological processes. The ubiquitous nature of sperm-egg interactions during and following fertilization suggest that these findings will have relevance to the reproductive biology to a wide range of animals, including endangered species and humans.