The Potential Role Of As-sumo-1in The Embryonic Diapause Process And Early Embryo Development Of Artemia Sinica

During embryonic development of Artemia sinica, environmental stresses induce theembryo diapause phenomenon, required to resist apoptosis and regulate cell cycle activity.The small ubiquitin-related modifier-1(SUMO), a reversible post-translational proteinmodifier, is a ubiquitin-related protein that plays an important role in embryo development.SUMO regulates multiple cellular processes, including nuclear transport, transcription,chromosome segregation, gene expression, genomic stability, development and otherbiological processes. The molecular mechanism of diapause and diapause termination remainsunknown, and the role of As-sumo-1in this processes and in early embryo development ofArtemia sinica is not well understood. In this study, the complete cDNA sequences of thesumo-1homolog, sumo ligase homolog, caspase-1homolog and cyclin B homolog fromArtemia sinica were cloned. The mRNA expression patterns of As-sumo-1, sumo ligase,caspase-1, cyclin B and the location of As-sumo-1were investigated.SUMO-1, p53, Mdm2,Caspase-1, Cyclin B and Cyclin E proteins were analyzed during different developmentalstages of the embryo of A. sinica. Small interfering RNA (siRNA) was used verify thefunction of sumo-1in A. sinica. The full-length cDNA of As-sumo-1was476bp, encoding a92amino acid protein. The As-sumo ligase cDNA was966bp, encoding a245amino-acidprotein. The caspases-1cDNA was1556bp encoding, a343amino acid protein, and thecyclin B cDNA was739bp encoding a133amino acid protein. The expressions of As-sumo-1,As-caspase-1and As-cyclin B were highest at the10h stage of embryonic development, andAs-sumo ligase showed its highest expression at0h. The expression of As-SUMO-1showedno tissue or organ specificity. Western blotting showed high expression of As-SUMO-1, p53,Mdm2, Caspase-1, Cyclin B and Cyclin E at the10h stage. The siRNA caused abnormaldevelopment of the embryo, with increased malformation and death rates. The conclusion wasthat sumo-1，sumo ligase，caspase-1，cyclin B, these gene about cell cycle regulation and cellapoptosis all increased for material reserves from0h to10h, expression quantity of thesegenes were all decreased from15h for cell differentiation, so the expression quantity allmaintain in a basal level. The results of Western blot could also verify the conclusion.As-SUMO-1is a crucial regulation and modification protein resumption of embryonicdiapause and early embryo development of Artemia sinica. It plays an important role inregulation and modification of the cell cycle and apoptosis, inhibiting proteins such as Cyclin B, Cyclin E, Caspase-1, p53and Mdm2.