Fig. 4.

Dynamic expression of mother-enriched proteins in single cells as a function of mother cell age. Mother cells were tracked using a microfluidic device and a time-lapsed microscope. GFP intensities of C-terminal–tagged Did2p (A) and Tpo3p (B) were measured in individual mother cells as well as in their daughters. (Left) GFP intensity in individual mother cells, where each colored line represents one cell. (Right) Mean and SD of the GFP intensity in mother cells and in daughter cells produced by mother cells at a given age. The red line is the ratio of the means of the mother and daughter cells.