Ageing and fertility are intertwined. Germline loss extends the lifespan in various organisms, termed gonadal longevity. However, the original longevity signal from the somatic gonad remains poorly understood. Here, we focused on the interaction between germline stem cells (GSCs) and their niche, the distal tip cells (DTCs), to explore the barely known longevity signal from the somatic gonad in C. elegans. We found that removing germline disrupts the cell adhesions between GSC and DTC, causing a significant transcriptomic change in DTC through hmp-2/β-catenin and two GATA transcription factors, elt-3 and pqm-1 in this niche cell. Inhibiting elt-3 and pqm-1 in DTC suppresses gonadal longevity. Moreover, we further identified the TGF-β ligand, tig-2, as the cytokine from DTC upon the loss of germline, which evokes the downstream gonadal longevity signalling throughout the body. Our findings thus reveal the source of the longevity signalling in response to germline removal, highlighting the stem cell niche as a critical signalling hub in ageing.

中文翻译：

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秀丽隐杆线虫的种系丧失通过破坏微环境和干细胞之间的粘附来延长寿命。


衰老和生育力是交织在一起的。种系损失延长了各种生物体的寿命，称为性腺寿命。然而，来自体细胞性腺的原始长寿信号仍然知之甚少。在这里，我们重点关注生殖干细胞 (GSC) 与其生态位远端细胞 (DTC) 之间的相互作用，以探索来自线虫体细胞性腺的鲜为人知的长寿信号。我们发现，去除种系会破坏 GSC 和 DTC 之间的细胞粘附，通过 hmp-2/β-catenin 和该微环境细胞中的两个 GATA 转录因子 elt-3 和 pqm-1 引起 DTC 的显着转录组变化。抑制 DTC 中的 elt-3 和 pqm-1 可抑制性腺寿命。此外，我们进一步鉴定出 TGF-β 配体 tig-2 是种系丧失后来自 DTC 的细胞因子，它会引起全身下游性腺长寿信号传导。因此，我们的研究结果揭示了响应种系去除的长寿信号的来源，强调干细胞生态位作为衰老过程中的关键信号中心。