Methods for Single-Cell Pulse-Chase Analysis of Nuclear Components

Pulse-chase methods offer powerful tools for following the evolution of a biological system over time, but are usually limited to ensemble measurements of the average behavior of very large numbers of cells. Here we describe three methods ranging from a true pulse-chase, through selective regional photoactivation, to pharmacological induction of an altered protein state, which can be applied to time-dependent studies at the single-cell level. These methods are exemplified by experimental protocols to follow region-selective nuclear envelope targeting of nascent phospholipids, a nascent nuclear lamin protein (lamin B1), and an immature lamin precursor (prelamin A).