dsGFP as exogenous control on RNAi assays and its effects on gene expression in Apis mellifera

Double stranded RNAs are used to induce gene silencing in functional studies. In Apis mellifera green fluorescent protein (GFP) dsRNA (dsGFP) has been used as an exogenous control as its sequence has no homology in honeybee genome. However, some undesirable effects are observed after dsGFP treatment. A microarray approach comparing gene expression differences between untreated and dsGFP treated groups, containing honeybees workers in two different developmental stages, pre-pupae and light-brown eyed pupae, were used to test the reliability of dsGFP as a control for RNAi experiments. According to these microarrays results dsGFP can be used as a control in RNAi assays as long as the affected genes are taken into account in the analysis. Analysis used loop-design to compare dsGFP treated and noon-treated workers in pre-pupae and light-brown-eyed pupae stages.