EAGER: RUI: Elucidating the role of exosomes in the regulation of steroidogenesis

外泌体是最近发现的小的膜结合颗粒，由细胞分泌到血液中，携带生物分子，可以重新编程受体细胞并启动新功能。尽管生物医学对外泌体作为生物标志物和治疗方法感兴趣，但它们的自然生理功能仍然未知。本研究探讨了外泌体的一个潜在作用，即作为内分泌腺（肾上腺、卵巢和睾丸）与其他只能在特定情况下合成激素的组织或器官之间的沟通纽带。使用新开发的方法，本项目将在蜥蜴模型中确定源自内分泌细胞的外泌体是否携带必要的生化信息，以启动非内分泌器官中局部类固醇激素的产生。在许多生物过程中都观察到这种激素产生的位置变化，包括前列腺癌、更年期、免疫细胞发育和动物的非繁殖性攻击。这项研究可能为这些不同的过程提供一个统一的机制，同时也为一些本科生的跨学科培训奠定基础，包括那些来自传统上代表性不足的群体的学生。该项目还将支持开发本科实验课程中的动手活动，影响更多的学生。通过学生的培训和合作，这项研究可能会对外泌体在激素功能、动物生理和行为中扮演的隐藏角色产生新的见解和未来的调查。外泌体是分泌到血浆中的纳米大小的囊泡，携带核酸和其他分子，可以改变受体细胞的表型，但其内在的有机功能仍未被研究和未知。本研究验证了外泌体参与调节局部类固醇激素合成的假设，当“非内分泌”组织（如肝、肠）合成生物活性类固醇时，外泌体将从内分泌腺体转移必要的类固醇生成酶mRNA以启动这一过程。利用Anolis蜥蜴模型系统，本研究将测试外泌体是否对肾上腺外糖皮质激素合成和性腺外性类固醇激素合成都是必要的。本研究首先旨在利用纳米颗粒跟踪分析确定局部类固醇生成是否会增加血浆外泌体分泌。第二个目的是用靶向引物的RT-PCR记录血浆外泌体是否含有甾体生成酶mRNA。第三个目标是使用一种新的药物来阻断外泌体的分泌，以测试其对局部类固醇生成的必要性。使用新的技术和测试范式，将测试非内分泌组织中激活类固醇生成机制的统一和普遍机制。mRNA通过外泌体在组织间的传递来调节生理功能和行为，将改变目前对细胞间通讯的理解，并对生物学的许多领域产生影响。这个项目也为年轻的生物学家提供科学培训，包括那些来自代表性不足的群体的生物学家，毫无疑问将导致关于外泌体在类固醇调节功能中的作用的合作和新的生物学问题。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Exosomes are recently discovered small membrane-bound particles that are secreted into blood by cells, carrying biomolecules that may reprogram recipient cells and initiate new functions. Despite biomedical interest in exosomes as biomarkers and therapeutics, their natural physiological function remains unknown. This research explores one potential role of exosomes, as communication links between endocrine glands (the adrenal glands, ovaries, and testes) and other tissues or organs which can only synthesize hormones under certain circumstances. Using newly developed methods, this project will determine whether exosomes originating from endocrine cells carry the necessary biochemical information to initiate local steroid hormone production in non-endocrine organs, in a lizard model. Such location shifts in hormone production are observed in many biological processes, including prostate cancer, menopause, immune cell development, and non-breeding aggression in animals. This research may provide a unifying mechanism for these diverse processes, while also serving as the foundation for the interdisciplinary training of several undergraduate students, including those from traditionally underrepresented groups. The project will also support development of hands-on activities in undergraduate laboratory courses, impacting more students. Through student training and collaborations, this research will likely lead to new insights and future investigations on the hidden roles that exosomes play in hormonal function, animal physiology, and behavior.Exosomes are nanosized vesicles secreted into plasma that carry nucleic acids and other molecules that can alter phenotypes of recipient cells, but their intrinsic organismal functions remain unstudied and unknown. This research tests the hypothesis that exosomes are involved in the regulation of local steroid hormone synthesis, which occurs when “non-endocrine” tissues (e.g., liver, intestine) synthesize bioactive steroids, with exosomes serving to transfer necessary steroidogenic enzyme mRNA from endocrine glands to initiate the process. Using the Anolis lizard model system, this research will test if exosomes are necessary for both extra-adrenal glucocorticoid hormone synthesis and extra-gonadal synthesis of sex steroid hormones. This study first aims to determine if local steroidogenesis increases plasma exosome secretion using nanoparticle tracking analysis. The second aim will document if plasma exosomes contain steroidogenic enzyme mRNA using RT-PCR with targeted primers. The third aim will use a new pharmacological agent to block exosome secretion to test its necessity for local steroidogenesis. Using novel techniques and testing paradigms, a unifying and ubiquitous mechanism for activating steroidogenic machinery in non-endocrine tissues will be tested. The transfer of mRNA between tissues via exosomes to regulate physiological functions and behavior will transform current understanding of cell-to-cell communication, with implications for many fields of biology. This project also serves to provide scientific training for young biologists, including those from underrepresented groups, and will doubtlessly lead to collaborations and new biological questions on the role of exosomes in steroid-regulated functions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.