Wee (cell cycle)

Wee is a protein that operates at the G2 to metaphase checkpoint. Wee becomes active if errors occur in the DNA synthesis phase. It blocks entry into metaphase until the problem is resolved. Like Rb, wee becomes inactive when hyperphosphorylated.

Its name comes from the Scottish/Irish slang word wee, meaning small. This is because when mutated, the cells with this mutation exhibit a smaller than usual phenotype. The protein's discoverer, Paul Nurse, was Scottish.