how to calculate the percentage of the cell cycle spent in each stage. give one example

Question

anonymous · Answer

a few methods:
1. the first using stage specific markers, specifically: antibodies (Ab) against
ki67 - pan cycling cell  g1-s-g2-m
late g2-m :phospho histone 3
brdu - a thymidine analogue for dna synthesizing cells - namely s phase
by staining for these markers one can directly or indriectly (substracting) the relative periods in each phase by prevalence of markers.

2. by dna content analysis in facs 

one peak for 2n content - namely g0 g1. 2nd peak of 4n content - g2m. a mid zone with variable dna content corresponding to synthesis of dna - s phase