cDNA cloning, sequence analysis and expression profiling of HaKettin1 gene from Helicoverpa armigera

[Objective] To clone the full length cDNA sequence of Kettin gene from Helicoverpa armigera and analyze its expression profiles in the life cycle of H. armigera development. [Methods] Using multiple RT-PCR and 5'-, 3'-RACE to clone the full length cDNA sequence of HaKettin1, and semi-quantitative RT-PCR to analyze the expression profiles. [Results] The full length of HaKettin1 cDNA sequence is 13 805 bp, containing an open reading frame of 13 365 bp. The deduced amino acid sequence consists of 4 454 amino acids, with molecular mass about 504.3 kD. The results of expression profiles showed HaKettin1 was expressed in all the cycle of insect life, and the expression of HaKettin1 at larval stage was higher than at other developmental stages. [Conclusions] Percent identity of HaKettin1 protein and Bombyx mori Kettin protein is 90%, suggesting that Kettin proteins are much conserved among Lepidoptera insects. The results of expression profiles suggest that HaKettin1 plays an important role in the development of H.