Genetic control of reproductive hierarchies in honeybee colonies (Apis mellifera)
Final Report Abstract
We were able to identify the homologue of the Drosophila gemini gene as the gene that controls thelytoky in worker honeybees. This gene is of great importance for the control of reproductive dominance in honeybees in general. Beside its identification we also clarified its mode of action by gene expression studies. Alternative splicing and the amount of different gemini transcripts covary with the different modes of parthenogenesis and with the worker’s different reproductive states. A two-exon-switch controls the worker’s reproductive capacity and its mode of parthenogenesis. Moreover, we identified the th allelic form of the gene as an intronic splice enhancer motif of nine nucleotides, flanking one of the alternate spliced exons. We suggest this mutation in A. m. capensis to alter the normal gemini splice pattern of altruistic workers, changing self-sacrificing organisms into social parasites. We tried to interfere the gene cascades regulated and the phenotypic effects caused by th by RNA interference but failed to reach the ovaries as a target tissue. More efforts to achieve successful targeting of honeybee ovaries are needed including the development of novel application techniques and modified target molecules to allow for tissue specific knock down of gene expression in the honeybee.
