Animal Ecology, Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden.
Department of Environmental and Biosciences, Halmstad University, Halmstad, Sweden.
Aging Cell. 2024 Nov;23(11):e14290. doi: 10.1111/acel.14290. Epub 2024 Jul 31.
Germline regulates the expression of life-history traits and mediates the trade-off between reproduction and somatic maintenance. However, germline maintenance in itself can be costly, and the costs can vary between the sexes depending on the number of gametes produced across the lifetime. We tested this directly by germline ablation using glp-1 RNA interference (RNAi) in a dioecious nematode Caenorhabditis remanei. Germline removal strongly increased heat-shock resistance in both sexes, thus confirming the role of the germline in regulating somatic maintenance. However, germline removal resulted in increased lifespan only in males. High costs of mating strongly reduced lifespan in both sexes and obliterated the survival benefit of germline-less males even though neither sex produced any offspring. Furthermore, germline removal reduced male growth before maturation but not in adulthood, while female growth rate was reduced both before and especially after maturation. Thus, germline removal improves male lifespan without major growth costs, while germline-less females grow slower and do not live longer than reproductively functional counterparts in the absence of environmental stress. Overall, these results suggest that germline maintenance is costlier for males than for females in C. remanei.
生殖细胞系调节生活史特征的表达，并介导繁殖和体细胞维持之间的权衡。然而，生殖细胞系本身的维持可能是有代价的，而且由于一生中产生的配子数量不同，代价在性别之间可能会有所不同。我们通过在雌雄同体的线虫 Caenorhabditis remanei 中使用 glp-1 RNA 干扰 (RNAi) 进行生殖细胞系消融直接测试了这一点。生殖细胞系的去除强烈增加了两性的热休克抗性，从而证实了生殖细胞系在调节体细胞维持中的作用。然而，生殖细胞系的去除仅导致雄性寿命延长。交配的高代价强烈缩短了两性的寿命，并消除了无生殖细胞系雄性的生存优势，尽管两性都没有产生任何后代。此外，生殖细胞系的去除减少了雄性在成熟前的生长速度，但不会减少成年后的生长速度，而雌性的生长速度在成熟前和特别是成熟后都降低了。因此，生殖细胞系的去除提高了雄性的寿命，而不会带来重大的生长代价，而没有生殖细胞系的雌性在没有环境压力的情况下比具有生殖功能的雌性生长速度更慢，寿命也更短。总的来说，这些结果表明，在 C. remanei 中，生殖细胞系的维持对雄性比雌性代价更高。
