背景:海参表现出再生受损或丢失的组织和器官的显着能力,使它们成为研究再生过程和机制的优秀模型系统。它们也可以通过横向裂变无性繁殖,前体和后体可以独立再生。尽管最近关注肠道再生,海参体壁再生的分子机制仍不清楚。
结果:在这项研究中,在热带海参中诱导了横向裂变,Holothurialeucosplitota,通过使用橡皮筋进行限制。组织学检查显示,第3天胶原纤维降解和松动,随后在再生的第7天密度增加,但结缔组织解体。在0-,人工诱导裂变后3天和7天。通过GO术语和KEGG数据库对差异表达基因进行分类和富集,分别。观察到与细胞外基质重塑相关的基因上调,而多能性因子Myc的下调,检测到Klf2和Oct1,尽管Sox2表达上调。此外,这项研究还确定了Wnt中转录因子的表达逐渐下降,河马,TGF-β,和MAPK信号通路。此外,与发育相关的基因变化,应激反应,凋亡,并观察到细胞骨架的形成。通过原位杂交进一步证实了相关基因的定位。
结论:H.leucospliota体壁的早期再生与细胞外基质的降解和随后的重建有关。多能性因子参与再生过程。发现多种参与调节细胞增殖的转录因子逐渐下调,表明细胞增殖减少。此外,与发育有关的基因,应激反应,凋亡,细胞骨架的形成也参与了这一过程。总的来说,这项研究为全身再生的机制提供了新的见解,并揭示了潜在的跨物种再生相关基因。
BACKGROUND: Sea cucumbers exhibit a remarkable ability to regenerate damaged or lost tissues and organs, making them an outstanding model system for investigating processes and mechanisms of regeneration. They can also reproduce asexually by transverse fission, whereby the anterior and posterior bodies can regenerate independently. Despite the recent focus on intestinal regeneration, the molecular mechanisms underlying body wall regeneration in sea cucumbers still remain unclear.
RESULTS: In this study, transverse fission was induced in the tropical sea cucumber, Holothuria leucospilota, through constrainment using rubber bands. Histological examination revealed the degradation and loosening of collagen fibers on day-3, followed by increased density but disorganization of the connective tissue on day-7 of regeneration. An Illumina transcriptome analysis was performed on the H. leucospilota at 0-, 3- and 7-days after artificially induced fission. The differential expression genes were classified and enriched by GO terms and KEGG database, respectively. An upregulation of genes associated with extracellular matrix remodeling was observed, while a downregulation of pluripotency factors Myc, Klf2 and Oct1 was detected, although Sox2 showed an upregulation in expression. In addition, this study also identified progressively declining expression of transcription factors in the Wnt, Hippo, TGF-β, and MAPK signaling pathways. Moreover, changes in genes related to development, stress response, apoptosis, and cytoskeleton formation were observed. The localization of the related genes was further confirmed through in situ hybridization.
CONCLUSIONS: The early regeneration of H. leucospilota body wall is associated with the degradation and subsequent reconstruction of the extracellular matrix. Pluripotency factors participate in the regenerative process. Multiple transcription factors involved in regulating cell proliferation were found to be gradually downregulated, indicating reduced cell proliferation. Moreover, genes related to development, stress response, apoptosis, and cell cytoskeleton formation were also involved in this process. Overall, this study provides new insights into the mechanisms of whole-body regeneration and uncover potential cross-species regenerative-related genes.