Abstract: 【Aim】 This study aims to clone a Bcl-2 family member gene from the silkworm, Bombyx mori, and explore its expression profiles and roles in different larval tissues and developmental stages of the moth. 【Methods】 BmBuffy was cloned using rapid amplification of cDNA ends (RACE) method. RT-PCR and qPCR were used to detect the gene expression profiles. The chromosome localization of this gene was conducted using SSR markers. 【Results】 The Bcl-2 family member gene cloned in B. mori was named BmBuffy, which is located on chromosome No. 4, coding a protein of 292 aa with an estimated molecular weight of 57.8 kDa and pI of 9.94. Its encoded protein also possesses a Bcl-2 like superfamily domain between 130-231 residues. Phylogenetic analysis revealed that BmBuffy is homologous to DmBuffy of Drosophila melanogaster with 27% amino acid sequence identity. The expression profiles in different larval tissues showed that BmBuffy had the highest expression level in Malpighian tubules. There was significant variation in the transcription level of BmBuffy in different developmental stages including metamorphosis. 【Conclusion】 BmBuffy has the typical Bcl-2 family domain, BmBuffy is located on chromosone No.4, and BmBuffy might play a role in the alteration of tissue physiology during metamorphosis. This study lays a foundation for further study on the function of Bcl-2 family genes in B. mori.

Key words: Bombyx mori , Bcl-2 family, gene cloning, expression profiling, chromosome localization