Figure 1.

Musashi regulates cell cycle progression through distinct translational control mechanisms in oocytes and in stem/progenitor cells. Musashi promotes cell cycle progression in mammalian stem cells by repression of mRNA translation (top). Similarly, Musashi promotes cell cycle progression in Xenopus oocytes, although by activation rather than repression of mRNA translation (bottom). It is unclear whether Musashi plays a role in during arrest of cell cycle progression in either differentiating stem cells or in immature oocytes.