Elucidating function of the novel PINX1-related protein, Chigno, in reproductive stem cells and development

项目总结： 生殖系干细胞(GSC)的生态位功能是确保生物体中持续的配子生产， 有性繁殖。干细胞调节失调也与发育障碍、癌症、 不孕不育和衰老。在苍蝇和哺乳动物中，GSC与周围环境之间的交流 SOMA调节干细胞维持和分化之间的平衡。然而，新的和 调节这些过程的未知机制仍在被发现--需要进一步的研究。 本提案旨在阐明一种新的PINX1相关蛋白CG11180/无子女Gambino的功能 (Chigno)，对果蝇生殖干细胞行为和发育的调控 黑猩猩。 Chigno是一种新的果蝇G-Patch结构域蛋白，与哺乳动物肿瘤相关 抑制器，PINX1。我们之前将Chigno确定为按时间顺序不合适的绑定合作伙伴 形态发生(Chinmo)，成年果蝇睾丸体细胞干细胞行为的关键调节因子。 我们实验室的本科生和硕士生研究人员收集的初步数据显示，Chigno是 在幼虫和成虫睾丸，以及果蝇卵巢和早期胚胎中表达。在成人睾丸中，Chigno 专门在睾丸顶端观察到，那里有生殖系干细胞(GSC)的壁龛。在这里，就是它 在生殖细胞和体细胞囊干细胞(CySCs)及其后代中均可检测到 生殖系行为。我们还发现，成年CySCs和早期囊泡细胞中Chigno基因的敲除导致了CySC 生殖细胞肿瘤的形成，以及睾丸顶端上皮细胞的扩张，这可能 与更改的CySC身份有关。此外，躯体Chigno枯竭会导致睾丸和卵巢 变得不育。 这一方案中的实验重点是了解Chigno在调节睾丸干中的作用。 细胞自我更新、分化和细胞命运维持(目标1)，了解Chigno蛋白的功能 分子水平(目标2)，并评估Chigno是否在睾丸以外的组织中发挥功能，包括 果蝇卵巢和胚胎组织(目标3)。鉴于Chigno对生育力和睾丸干细胞的影响 行为，以及G-Patch/PINX1相关蛋白在一系列细胞过程中的不同功能， 对Chigno功能的研究为阐明新的调控机制提供了极大的希望 在一系列生物体中的生育、干细胞行为和发育。

PROJECT SUMMARY: The germline stem cell (GSC) niche functions to ensure continuous gamete production in organisms that reproduce sexually. Dysregulation of stem cells has also been linked to developmental disorders, cancer, infertility, and senescence. In flies and mammals alike, communication between GSCs and the surrounding soma regulates the balance between stem cell maintenance and differentiation. However, new and unexplored mechanisms regulating these processes are still being discovered - necessitating further enquiry. This proposal strives to elucidate the function of a novel PINX1-related protein, CG11180/Childless Gambino (Chigno), in regulating reproductive stem cell behavior and development in the fruit fly, Drosophila melanogaster. Chigno is a novel G-patch domain-containing protein in flies that is related to the mammalian tumor suppressor, PINX1. We previously identified Chigno as a binding partner of Chronologically inappropriate morphogenesis (Chinmo), a key regulator of somatic stem cell behavior in the adult Drosophila testis. Preliminary data collected by undergraduate and master’s student researchers in our lab show that Chigno is expressed in larval and adult testes, as well as Drosophila ovaries and early embryos. In adult testes, Chigno is observed specifically at the testis apex, which houses the germline stem cell (GSC) niche. Here, it is detected both in germ cells as well as somatic cyst stem cells (CySCs) and their progeny which regulate germline behavior. We also find that Chigno knockdown in adult CySCs and early cyst cells results in CySC over-production, formation of germ cell tumors, and an expansion of epithelial cells at the testis apex that may be linked to altered CySC identity. Furthermore, somatic Chigno depletion causes both testis and ovaries to become infertile. Experiments in this proposal are focused on understanding the role of Chigno in regulating testis stem cell self-renewal, differentiation, and cell fate maintenance (Aim 1), understanding Chigno protein function at the molecular level (Aim 2), and assessing whether Chigno functions in tissues other than the testis, including Drosophila ovaries and embryonic tissues (Aim 3). Given Chigno’s impact on fertility and testes stem cell behavior, as well as the diverse functions of G-patch/PINX1-related proteins in a range of cellular processes, the proposed studies into Chigno function hold great promise for elucidating novel mechanisms controlling fertility, stem cell behavior, and development in a range of organisms.