Fluorescent indicators for simultaneous reporting of all four cell cycle phases

Abstract

A robust method for simultaneous visualization of all four cell cycle phases in living cells is highly desirable. We developed an intensiometric reporter of the transition from S to G2 phase and engineered a far-red uorescent protein, mMaroon1, to visualize chromatin condensation in mitosis. We combined these new reporters with the previously described Fucci system to create Fucci4, a set of four orthogonal uorescent indicators that together resolve all cell cycle phases.