Overexpression of human cyclin A advances entry into S phase.
Cyclin A is a cell cycle regulatory protein that functions in mitotic and S-phase control in mammalian cells. Using a genomic construction corresponding to the human cyclin A gene under the control of its own promoter, we have established stable transfectants overexpressing cyclin A protein. Experiments assisted by laser scanning image cytometry showed that this overexpression begins from late G1 phase onwards and is therefore cell cycle-regulated in this model. We demonstrated that this overexpression advances entry into S phase, leading to a contraction of the overall cell generation time. These results provide evidence that cyclin A can be a rate-limiting factor with respect to the control of the transition to S phase in mammalian cells.
Rosenberg
A R
AR
INSERM U370, Institut Necker, Paris, France.
Zindy
F
F
Le Deist
F
F
Mouly
H
H
Métézeau
P
P
Bréchot
C
C
Lamas
E
E
D016213:Cyclins / Q000096:biosynthesis* / Q000235:genetics; D004247:DNA / Q000096:biosynthesis; D016193:G1 Phase; D006367:HeLa Cells; D006801:Humans; D016196:S Phase; D014162:Transfection
D016213:Cyclins; D004247:DNA