摘要：SNAIL transcriptional factors are key regulators during development and disease. They arose early during evolution, and in cnidarians such as Nematostella vectensis , Nv SNAILA/B are detected in invaginating tissues during gastrulation. The function of SNAIL proteins is well established in bilaterians but their roles in cnidarians remain unknown. The structure of Nv SNAILA and B is similar to the human SNAIL1 and 2, including SNAG and zinc-finger domains. Here, we performed a molecular analysis on localization and mobility of Nv SNAILA/B using mammalian cells and Nematostella embryos. Nv SNAILA/B display nuclear localization and mobility similar to Hs SNAIL1/2. Strikingly, Nv SNAILA is highly enriched in the nucleoli and shuttles between the nucleoli and the nucleoplasm. Truncation of the N-terminal SNAG domain, reported to contain Nuclear Localization Signals, markedly reduces nucleolar levels, without effecting nuclear localization or mobility. Truncation of the C-terminal zinc-fingers, involved in DNA binding in higher organisms, significantly affects subcellular localization and mobility. Specifically, the zinc-finger domains are required for nucleolar enrichment of Nv SNAILA. Differently from SNAIL transcriptional factors described before, Nv SNAILA is specifically enriched in the nucleoli co-localizing with nucleolar markers even after nucleolar disruption. Our findings implicate additional roles for SNAG and zinc-finger domains, suggesting a role for Nv SNAILA in the nucleolus.
