Abstract:

Cell division and differentiation were processing in quantity from the fertilized eggs to larvae of the silkworm, Bombyx mori, but in diapause eggs embryonic development arrested in the G2 of cell division. In order to explore the molecular regulation in this developmental stage, the cyclin gene of B. mori was cloned according to the cyclin L1 sequence of Homo sapiens and named BmCcnl1. The ORF of BmCcnl1 is 1 254 bp, encoding a 417-amino acid protein and registered with GenBank accession number FJ889988. The predicted molecular weight and isoelectric point of BmCcnl1 protein were 49 kDa and 9.84, respectively analyzed by Protean software. The prokaryotic expression vector pET-21d-BmCcnl1 was constructed, and the expression product was present in inclusion bodies. The expression of the BmCcnl1 mRNA was detected using RT-PCR. The relative expression level of BmCcnl1 mRNA was stable in the embryonic stage of non-diapause eggs, but its expression was not detectable 72 h after oviposition. The results suggest that BmCcnl1 is related to the development regulation of the diapause and non-diapause eggs. The cloning and expression analysis of BmCcnl1 provide the basis for the research of the embryonic development and cell cycle regulation.

Key words: Bombyx mori, cyclin, clone, expression, diapause