We’re all told that cutting out sugar or consuming antioxidants can change our lives. But new PLOS Genetics research suggests that in the diets of honeybees, it’s the microRNAs that matter.
Honeybee larvae develop into distinct “castes,” including large, fertile queen bees and smaller, sterile worker bees. While worker bees eat “beebread,” a mix of pollen and honey, queen bees feast on royal jelly. Beebread is known to help induce larvae to develop into worker bees, and it contains molecules of genetic material known as microRNAs from plants. So, the study authors investigated the plant microRNAs commonly found in beebread to determine if they played a part in caste development.
Amazingly, the researchers found that certain plant microRNAs, which usually regulate plant gene expression, also acted on bees when consumed. Honeybees raised in the lab on simulated beebread supplemented with plant microRNAs developed more slowly and had a smaller body and smaller ovaries – being more “worker-like” – than bees raised without the supplements.
Further work will be required to fully elucidate the mechanism for this effect, but the scientists were able to show that one of the most common beebread microRNAs targets the TOR gene in bees, which is known to help determine caste.
Royal jelly was previously thought to be the key food that influences caste development. But this new research identifies a previously unknown function of beebread plant microRNAs in bee development; a fascinating example of how molecules can act not just across species but across kingdoms.
Image Credit: Drs. Xi Chen and Kegan Zhu
Research Article: Zhu K, Liu M, Fu Z, Zhou Z, Kong Y, Liang H, et al. (2017) Plant microRNAs in larval food regulate honeybee caste development. PLoS Genet 13(8): e1006946. https://doi.org/10.1371/journal.pgen.1006946