位于同一干细胞龛中的异种或同种干细胞之间竞争龛中适于自身生存的位置和调控信号的行为被称为干细胞竞争。恰当的竞争对维持干细胞群体的数目稳定、活力及特异的分化能力有重要意义。近年来相当数量的工作报道了干细胞竞争在发育和稳态维持中的重要作用及调控机制。然而干细胞竞争与衰老之间的关系尚不明确，其在衰老过程中的变化情况及对器官衰老的影响还未被报道。我们的前期研究发现，衰老精巢干细胞龛中的Lamin-B Receptor （LBR）蛋白发生错误聚积，其可能通过JAK-STAT信号导致包囊干细胞与生殖干细胞之间的竞争失衡，进而诱发生殖干细胞丢失。在本项目中，我们将利用精巢干细胞龛系统研究衰老过程中干细胞竞争的变化情况，揭示LBR介导衰老过程中干细胞竞争失衡的分子机制，探究LBR错误聚积的原因。我们的研究将有望揭示新的干细胞衰老机制，为研究干细胞衰老相关疾病发病机理及开发相应的治疗策略提供有利的理论依据。

The same or different kinds of stem cells which locate in the same stem cell niche will compete the right position and regulation signals, which is called stem cell competition. The proper competition is important for maintaining the stem cell population, fitness and the special ability of differentiation. For the past few years, a bunch of researches showed the functions and regulation methods of stem cell competition in the context of development and tissue homeostasis. However, the change, function and regulation mechanism of stem cell competition in aging process is still unknown. Our preliminary data show that Lamin-B Receptor (LBR) abnormally aggregates in the old cyst stem cell, which may disrupt the stem cell competition in Drosophila testis via JAK-STAT signaling, and in turn leads to the loss of germline stem cell in testis upon aging. Here, we plan to study the change of stem cell competition during testis aging, and explore the molecular mechanism of how LBR leads to the breakdown of stem cell competition in aged testis, and illuminate the cause of LBR abnormal aggregation. Our research may reveal a new mechanism of stem cell aging, and provide important data basis for studying the pathogenesis of stem cell age-associated human diseases and exploring new strategies for disease treatments.