Stem cell regulation in the wasp Copidosoma floridanum

描述（申请人提供）：干细胞自我更新和分化成其他细胞类型的能力使其成为生命科学家非常感兴趣的主题。生殖系干细胞是一类干细胞，仅产生与生殖系相关的细胞，包括卵子和精子，因此对于发育原因也很重要。生殖系干细胞在历史上被证明是具有挑战性的研究，因为它们在生物体中的稀缺性。佛罗里达拟寄生蜂（Copidosoma floridanum）是一种多胚性寄生蜂，它能产生相对丰富的生殖干细胞及其祖细胞，B）具有两个与生殖干细胞调控相关的显著发育过程，是研究生殖干细胞调控的理想生物。第一光滑floridanum是多胚的，这意味着成千上万的后代从一个卵子克隆发育，因此也有成千上万的生殖干细胞。多胚性部分是通过胚胎发生早期增殖增加而实现的。第二，同一窝的后代发育成形态上不同的幼虫种姓。最近的证据表明，种质，细胞质定义生殖系干细胞的前体，是需要这两个过程。切除C. floridanum减少增殖并消除生殖种姓的分化。在这里，我假设在早期干细胞调控的变化是负责在这个物种的多胚和种姓分化。这个建议的具体目的是通过使用观察和功能研究相结合的方法来测试关于含有细胞的生殖质在发育过程中应如何发挥作用的明确预测，从而评估我的假设。我研究的长期目标是了解生殖系和其他干细胞在发育过程中的功能。虽然生殖系干细胞对发育至关重要，并且与疾病有关，但人们对它们是如何形成的知之甚少。这项工作将有助于理解干细胞的分子控制以及它们在生物体中的变化。

DESCRIPTION (provided by applicant): The capacity of stem cells to self renew and differentiate into additional cell types has made them a subject of great interest to life scientists. Germline stem cells are a category of stem cells that give rise only to cells associated with the germline, including egg and sperm, and thus are also important for developmental reasons. Germline stem cells have historically proven challenging to study because of their scarcity in organisms. Copidosoma floridanum, a parasitic, polyembryonic wasp, is a promising organism in which to study germline stern cell regulation because a) they produce germline stem cells and their progenitors in relative abundance and b) they have two striking developmental processes associated with changes in germline regulation. First C. floridanum is polyembryonic meaning that thousands of offspring develop clonally from a single egg and therefore so too do thousands of germline stem cells. Polyembryony is achieved, in part, by increased proliferation early in embryogenesis. Secondly, offspring of the same brood develop into morphologically distinct larval castes. Recent evidence indicates that germ plasm, the cytoplasm defining germline stem cell precursors, is required for both of these processes. Ablation of germ plasm containing cells in C. floridanum decreases proliferation and eliminates differentiation of the reproductive caste. Here, I hypothesize that changes in early stem cell regulation are responsible for polyembryony and caste differentiation in this species. The specific aims of this proposal are to evaluate my hypothesis by testing explicit predictions about how germ plasm containing cells should act during development using a combination of observational and functional studies. The long-term goals of my study are to understand the function of germline and other stem cells during development. While germline stem cells are essential for development and have been linked to disease, very little is understood about how they are formed. This work will contribute to understanding the molecular controls of stem cells and how they vary among organisms.