Stem cells: Royal jelly component maintains stem cell pluripotency

The protein component of royal jelly (Royalactin) can maintain pluripotency in mouse embryonic stem cells according to a study published in Nature Communications. The work also identified the mammalian structural analog, Regina, which promotes similar effects on stem cell pluripotency and reveals an innate programme for stem cell self-renewal.

Royal jelly, the 'queen-maker' for the honey bee Apis mellifera, is known to have effects on mammals, affecting longevity, fertility, and regeneration. Major Royal Jelly Protein 1 (MRJP1, also known as Royalactin), has been found to be the functional component of royal jelly and shown to modulate effects on other species, suggesting that it might be activating conserved pathways. However, these conserved cellular signalling pathways have not yet been characterised.

Kevin Wang and colleagues found that Royalactin activates the pluripotency gene network in mouse embryonic stem cells and maintains these cells in culture in the absence of other factors that are usually required to maintain embryonic stem cells. When injected into mouse blastocysts, the Royalactin cultured cells were also capable of generating viable mice and were incorporated into their germ cells. The authors also identified a mammalian structural analog of Royalactin, which they called Regina. They found that Regina has a similar functional capacity to maintain mouse embryonic stem cell identity in cell culture. This suggests the existence of an evolutionary conserved pathway from bees to mammals, which might regulate distinct processes in each species. Further studies will help elucidate the role Regina might play in mammalian cells.