A new gene, SRP16, differentially expressed in the spermathecae of honeybee queens (Apis mellifera) related with reproduction status

Honey bee queens have the ability to store sperm in spermathecae for fertilizing eggs throughout their life. To investigate mechanisms for sperm storage in Apis mellifera, we employed suppression subtractive hybridization (SSH) to find differentially expressed fragments in spermathecae between virgin queens and newly mated queens. A new gene, named SRP16, was obtained by joining the SSH products with 5'-RACE and 3'-RACE. SRP16 is predicted to encode a 41 kDa protein with 363 amino acid residues. Its expression was found in the spermathecae dominantly in honey bee queens but not in honey bee workers, with the highest expression found in spermathecae of virgin and newly mated queens. SRP16 expression was weak in other tissues of queens other than in the spermathecae and showed no obvious change with reproductive status of queens. The results suggest that SRP16 may play important roles in sperm storage and honey bee reproduction.