First discovered in fruit flies in 1994 by a Japanese researcher, Makoto Nakamura, while working in Baltimore in the US, Musashi is named after the 17th century samurai warrior Musashi Miyamoto, who devised a fighting style of wielding two swords at the same time rather than just one. Rather than waving swords around, fruit flies with a faulty version of the Musashi gene have double rather than single bristles popping out over their bodies.
It’s now known that Musashi binds to certain RNAs - the molecular messages produced from active genes - and affects how they are processed and read by cells to make proteins. It seems to have a particular role in ensuring that stem cells in the nervous system maintain their stem-cell abilities. This explains the double bristle effect: fly bristles are made up from four cells - two are nerve cells, while the socket and bristle shaft are not. Without Musashi, there’s nothing to stop one of the nerve cells becoming a bristle shaft too.
There are a few mammalian versions of Musashi, which also seem to be involved in maintaining nerve stem cells and other stem cells around the body. Intriguingly, they get reactivated in some brain tumours and other cancer types, suggesting they might be causing cells to forget what they’re meant to be doing and revert back to more stem-like behaviours.
Check out this news story to find out how the Musashi gene might hold the key to better Zika virus vaccines and even a treatment for brain tumours.