Caste differentiation in the female honey bee is one of the most intriguing polyphenism phenomena. This developmental switch depends on the differential expression of entire suites of the genes involved in the larval fate between the queens and workers.
In this study, researchers from Zhejiang University, China compared the transcriptome differences between full-sister queen- (QL) and worker-destined larvae (WL) using high-throughput RNA-Seq. The transcriptome changes were investigated using the DEGs Package (DEGseq), which resulted in more than 4,500 differentially expressed genes (DEGs) between the castes. All of the DEGs were analysed using Web Gene Ontology Annotation Plot (WEGO) and then mapped using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. These results suggest that over 70% of the DEGs in each instar were more highly expressed in QL than in WL, possibly suggesting that the QL genes had higher transcriptional activity than the WL genes during differentiation. The same gene set is active (but differentially expressed) in both castes, which in turn result in dimorphic females.
These results could contribute to an in-depth study of the candidate genes during honey bee caste differentiation and improve our current understanding of the polyphenism phenomenon in insects.
Chen X, Hu Y, Zheng H, Cao L, Niu D, Yu D, Sun Y, Hu S, Hu F. (2012) Transcriptome comparison between honey bee queen- and worker-destined larvae. Insect Biochem Mol Biol [Epub ahead of print]. [article]