Cj. Mcnamee et al., CELL CYCLE-DEPENDENT MORPHOLOGICAL-CHANGES IN THE ACTIN CYTOSKELETON INDUCED BY AGENTS WHICH ELEVATE CYCLIC-AMP, Cell biology international, 19(9), 1995, pp. 769-775
Agents which increase the intracellular concentration of cyclic adenos
ine-5'-monophosphate, induce a highly arborised morphology in a propor
tion of sub-confluent Swiss 3T3 fibroblasts. During this process the o
rganisation of actin filaments progessively changes from a characteris
tic stress fibre pattern to leave a network of actin filaments within
each and every arborisation. Despite this massive reorganisation of th
e actin cytoskeleton no changes are observed in the extent of polymeri
sation of actin during arborisation. The proportion of cells in asynch
ronous cultures undergoing arborisation at maximal concentrations of a
gents reaches a maximum of 30%; suggesting that the effect might be me
diated only in cells during a restricted period of the cell cycle. Mor
e than 80% of serum-starved cells responded to these agents between 1
and 8 hours after readdition of serum, but not at other times, suggest
ing that the arborisation response can occur only in the G1 phase of t
he cell cycle.