Royal Jelly - Epigenetic Effects

Epigenetic Effects

The honey bee queens and workers represent one of the most striking examples of environmentally controlled phenotypic polymorphism. In spite of their identical clonal nature at the DNA level, they are strongly differentiated across a wide range of characteristics including anatomical and physiological differences, longevity of the queen, and reproductive capacity. Queens constitute the sexual caste and have large active ovaries, whereas workers have only rudimental inactive ovaries and are functionally sterile. The queen/worker developmental divide is controlled epigenetically by differential feeding with royal jelly; this appears to be due specifically to the protein royalactin. A female larva destined to become a queen is fed large quantities of royal jelly; this triggers a cascade of molecular events resulting in development into a queen. It has been shown that this phenomenon is mediated by an epigenetic modification of DNA known as CpG methylation. Silencing the expression of an enzyme that methylates DNA in newly hatched larvae led to a royal jelly-like effect on the larval developmental trajectory; the majority of individuals with reduced DNA methylation levels emerged as queens with fully developed ovaries. This finding suggests that DNA methylation in honey bees allows the expression of epigenetic information to be differentially altered by nutritional input.