Molecular characterization of cyclin B and its expression profile during oogenesis in the red swamp crayfish, Procambarus clarkii (Girard, 1852) (Decapoda, Astacidea)

Abstract

The maturation promoting factor (MPF), a complex of CDC2 (CDK1) and cyclin B, is a key regulator of controlling the G2/M phase transition in the meiotic maturation of the oocyte in multi-cellular organisms. In this study, full-length cDNA of cyclin B (Pc-cyclin B) from the red swamp crayfish,Procambarus clarkii, was cloned using the degenerate RT-PCR and RACE methods. The cDNA of Pc-cyclin B is 2595 bp in length and encoding a protein of 402 amino acids, with a calculated molecular mass of 45.75 kDa. Six potential cytoplasmic polyadenylation elements (CPE) as well as one signal sequences (AATAAA) were found in the 3′-UTR location. Semi-quantitative RT-PCR analysis revealed that the amount of cyclin B mRNA was highest in the ovary, followed by the heart (); and also significantly higher in the pre-vitellogenesis (pre-Vt) and primary-vitellogenesis (pVt) stages, while low in the tertiary-vitellogenesis and GVBD stages (), suggesting that differential expression of Pc-cyclin B is closely related to oogonial proliferation (mitosis) and oocyte meiotic maturation in this species of crayfish.