A queen is made not born: Epigenesis in honey bees
Every organism on earth is a product of a gene-environment interaction. In social insects such as honey bees, gene expression can be greatly modified by environmental factors. This generates huge contrasts between individuals in morphology, physiology and social behaviour. For example, a functional hive of western honey bees (Apis mellifera) has a legendary capacity to self organise into a productive, harmonious and enduring community. Each colony comprises highly specialised jobs from humble and industrious workers to a regal queen who is destined to exist for a few years as a cosseted egg-laying factory.
Remarkably, every bee in a hive shares an identical genome, but their growing ‘environment' has been skilfully crafted by the hive to generate desired outcomes. The nature of those epigenetic influences are now being revealed by Dr Ryszard Maleszka of the Molecular Genetics and Evolution group at the School of Biology.
Dr Maleszka has a particular interest in how a queen is made. Royal jelly fed to selected larvae by worker bees triggers a developmental journey that will lead to a fertile queen. Dr Maleszka and his colleagues discovered that they could mimic the royal jelly effect by silencing DNA methylation in a specific way. This capacity was made possible by their knowledge of the honey bee genome, and carries implications for wider nutritional control over global gene expression within the bee community. Indeed, these new molecular tools will help accelerate the young field of ‘sociogenomics' namely, the search forgenetic underpinnings of social life.
Beyond its relevance to insects, this work could have implications in human health too. Molecular processes that are common across all organisms are highly conserved, so that bees and humans still share similar genes and biochemical mechanisms. Understanding how royal jelly re-programmes genes in bees might be useful in probing major problems in human society such as obesity.