Expression Of Stem Cell Pluripotency Factors During Regeneration And The Early Development Of Earthworm Eisenia Foetida

Earthworm (Eisenia foetidd) has a potentiality to regenerate when damaged by an external force, such as plow and furrow, which is an important characteristic of earthworm to adapt to environment.The pluripotency genes are important for cell differentiation.The research focuses on the molecular mechanism of regeneration.Our study used common earthworm (Eisenia foetidd) to study earthworm regeneration.Through the method of homology sequence analysis and alignment, we successfully cloned pluripotency genes fragment and detected the pluripotency genes in different segments of earthworm and demonstrated their expression levels during early developmental stages.The main results are:1.We successfully cloned the pluripotency genes from Eisenia foetida, the full-length of Sox2(GenBank Accession number:KP637161) cDNA sequence is2354bp, including367bp of5'-UTR,844bp of3'-UTR and1143bp ORF.At the same time, we cloned partial sequence of OctA, Nanog, c-Myc and Lin28, sharing more than70%sequence identity with homologous sequences.2.We used q-RT-PCR to detect the level of pluripotency gene expression in different segments (head, clitellum and tail segment).The result showed that OctA and Nanog in clitellum were significantly higher than in head and tail segments, but other genes in three segments were not different significantly.lt showed that OctA and Nanog have tissue specificity, but Sox2, c-Myc and Lin28not.3.Expression levels of genes during regeneration in different segments (head, clitellum and tail segment) were detected by q-RT-PCR.The result showed that there was no significantly different at1d after amputation, but there was a significant up-regulation at4d-6d.The expression of genes during regeneration in different segments showed a similar expression pattern.4.The level of pluripotency gene expression during development in different segments was detected.The result showed:the expression of pluripotency genes are gradually increased from0d to21d, then decreased from21d to28d.It suggested expression patterns of these pluripotency genes were similar, and these genes may have a synergistic effect during the early development of Eisenia foetida.In conclusion, the pluripotency genes expression were up-regulated during regeneration of earthworm, the expression patterns of the genes during regeneration were similar to the expression pattern in early development.The regeneration process may involves cell pluripotency regulation, suggesting the cells source during regeneration was produced from dedifferentiation and differentiation of somatic cells.