||Human Homo sapiens
||Lemons JM et al., Quiescent fibroblasts exhibit high metabolic activity. PLoS Biol. 2010 Oct 19 8(10):e1000514. doi: 10.1371/journal.pbio.1000514. p.2 right column 2nd paragraphPubMed ID21049082
||"[Investigators] developed a model system that allows [them] to monitor
metabolic differences between proliferating and quiescent cells.
Primary dermal fibroblasts were expanded and analyzed while
actively proliferating, after 1 wk of growth to confluence (contact-inhibited
for 7 d [CI7]), after 2 wk of confluence (contact-inhibited
for 14 d [CI14]), or after 2 wk of confluence with serum
concentrations decreased for the final week from 10% to 0.1%
(contact-inhibited for 14 d and serum-starved for 7 d [CI14SS7]). Alternatively, fibroblasts were plated sparsely so that they did not
touch each other and induced into quiescence by serum starvation
and monitored after 4 d (serum-starved for 4 d [SS4]) or 7 d
(serum-starved for 7 d [SS7])."
||"In quiescent fibroblasts, the fraction
of cells with 2N DNA content increased so that 80% or more of
the cells were in the G0/G1 phase of the cell cycle (Figure 1A)."