Cells deleted for all G1 cyclins CLN1, CLN2 and CLN3 but provided with a methionine-regulatable MET3-CLN2 gene were periodically pulsed with methionine-free medium in the microfluidics flow-cell device of Charvin et al.( PLoS ONE. 2008 Jan 23;3(1):e1468). Green: Whi5-GFP; G1/S transcriptional repressor. Yellow: CDC10-YFP: marker of bud neck, appears at budding and disappears at cytokinesis. Bottom: bars indicate periods of induction with -Met.
Driving synchronized cell cycles with periodic pulses of the anaphase inducer Cdc20.
The essential gene CDC20 is placed under control of the galactose inducible GAL1 promoter. The microfluidics flow-cell device of Charvin et al.( PLoS ONE. 2008 Jan 23;3(1):e1468) was used to provide periodic pulses of galactose at a period sufficient for each blocked cell to complete its cell cycle and reaccumulate at a new cdc20-deficient block. Green: tubulin (TUB1-YFP) marking mitotic spindle; yellow: CDC10-YFP: marker of bud neck, appears at budding and disappears at cytokinesis. Bottom: bars indicate periods of induction with galactose.

Periodic Start driven in a flow cell
Cells deleted for all G1 cyclins CLN1, CLN2 and CLN3 but provided with a methionine-regulatable MET3-CLN2 gene were periodically pulsed with methionine-free medium in the microfluidics flow-cell device of Charvin et al.( PLoS ONE. 2008 Jan 23;3(1):e1468). Green: Whi5-GFP; G1/S transcriptional repressor. Yellow: CDC10-YFP: marker of bud neck, appears at budding and disappears at cytokinesis. Bottom: bars indicate periods of induction with -Met.

Wild-type budding yeast cell cycle
Septin (CDC10-YFP) marks bud neck and disappears at cytokinesis; tubulin (TUB1-GFP) marks spindle; elongates at anaphase and disassembles at telophase.

Copyright F. Cross, The Rockefeller University. Not for use without proper attribution