The cost and payout of age on germline regeneration and sexual maturation in Platynereis dumerilii.
The cost and payout of age on germline regeneration and sexual maturation in Platynereis dumerilii.
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杜梅里柳种系再生和性成熟的年龄成本和回报。
DOI：
10.1101/2024.01.22.576726
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发表时间：
2024
期刊：
影响因子：
--
通讯作者：
Özpolat,BDuygu
中科院分区：
文献类型：
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作者：
Metzger,Bria;Özpolat,BDuygu
在许多生物体中，再生，即重新长出丢失和受伤的身体部位，是一种通常随着年龄或发育转变（即变态、性成熟）而下降的能力。再生在能量上也是一个昂贵的过程，并且在再生和其他昂贵的过程（例如体细胞生长或有性生殖）之间发生权衡。在这里，我们研究了分节蠕虫 Platynereis dumerilii 的再生、繁殖和年龄的相互作用。 P. dumerilii 可以再生其整个后体轴及其生殖细胞，因此必须在受伤后执行两个昂贵的过程（体细胞和生殖细胞再生）。我们特别研究了年龄如何影响发育中的年轻生物体和年老生物体的生殖细胞再生和性成熟的成功。我们假设，发育较年轻的个体（即较低的投资状态，配子处于早期有丝分裂阶段）将比发育较老的个体（即较高的投资状态，配子处于成熟过程中）具有更高的再生成功率和更快地达到性成熟。令人惊讶的是，年老的截肢线虫比年轻的截肢线虫生长得更快、成熟得更早，尽管它们必须再生更多的节段并恢复已经开始进行配子发生的更昂贵的生殖细胞。为了分析不同阶段的生殖细胞再生，我们使用杂交链反应来分析生殖系标记 vasa。我们发现，再生线虫早在截肢后 14 天就开始用生殖细胞簇重新填充新的节段。此外，在新再生节段的广泛区域中观察到vasa表达，这与线虫在角簇扩张之前的正常生长或再生期间的表达模式不同。未来的研究将集中于确定再生中角簇的确切来源。
Regeneration, regrowing lost and injured body parts, is an ability that generally declines with age or developmental transitions (i.e. metamorphosis, sexual maturation) in many organisms. Regeneration is also energetically a costly process, and trade-offs occur between regeneration and other costly processes such as somatic growth, or sexual reproduction. Here we investigate the interplay of regeneration, reproduction, and age in the segmented worm Platynereis dumerilii. P. dumerilii can regenerate its whole posterior body axis, along with its reproductive cells, thereby having to carry out the two costly processes (somatic and germ cell regeneration) after injury. We specifically examine how age affects the success of germ cell regeneration and sexual maturation in developmentally young versus old organisms. We hypothesized that developmentally younger individuals (i.e. lower investment state, with gametes in early mitotic stages) will have higher regeneration success and reach sexual maturation faster than the individuals at developmentally older stages (i.e. higher investment state, with gametes in the process of maturation). Surprisingly, older amputated worms grew faster and matured earlier than younger amputees, even though they had to regenerate more segments and recuperate the more costly germ cells which were already starting to undergo gametogenesis. To analyze germ cell regeneration across stages, we used Hybridization Chain Reaction for the germline marker vasa. We found that regenerated worms start repopulating new segments with germ cell clusters as early as 14 days post amputation. In addition, vasa expression is observed in a wide region of newly-regenerated segments, which appears different from expression patterns during normal growth or regeneration in worms before gonial cluster expansion. Future studies will focus on determining the exact sources of gonial clusters in regeneration.