Molecular Cloning and Expression Profile of Bm-DnaJ 5 Gene in the Silkworm,Bombyx mori

DnaJ protein is a regulatory protein.A Bombyx mori EST was identified which encodes the DnaJ protein from silkworm pupa cDNA database and a cDNA sequence named Bm-DnaJ5 was cloned from the Bombyx mori.The deduced protein contains 351 amino acids,its molecular weight is 38.93 kD and theoretical pI is 9.25.The profile of spatio-temporal expression of Bm-DnaJ 5 identified by real-time PCR indicated that it had a broad distribution in various tissues from the 5th instar larvae and pupae.Quantitative analysis showed that expression of Bm-DnaJ 5 in the 5th instar larvae was the highest in testis(1.16×108copy numbers/μg),was relatively higher in brain,midgut,fore silk gland and wing discs,and was the lowest in tracheal cluster(1.84×104 copy numbers/μg).The results also showed that Bm-DnaJ 5 was expressed in six tissues of the middle pupal stage of Bombyx mori,with relatively higher levels(8.79×107copy numbers/μg and 1.78×107copy numbers/μg) in eyes and testis and lowest level in ovary(1.94×105copy numbers/μg).