Effect of the kinase inhibitor 2-aminopurine on the cell cycle stage-dependent phosphorylation state of the retinoblastoma protein.
We investigated the effect of 2-aminopurine (2-AP) on the cell cycle stage-dependent phosphorylation state of the retinoblastoma growth suppressor protein (pRB). Our results suggest that 2-AP does not affect dephosphorylation of pRB scheduled during metaphase/anaphase of mitosis, even though 2-AP-treated cells never enter metaphase or anaphase. Phosphorylation of pRB, which is important for G1 exit, appeared to be impeded by 2-AP late during G1, coincident with a slowing of G1 cell progression into S phase. The significance of these data with regard to cell cycle regulation is discussed.
Metheny
L J
LJ
Department of Medicine, University of Rochester School of Medicine and Dentistry, New York, USA.
Nelson
D A
DA
Ludlow
J W
JW
D015075:2-Aminopurine / Q000494:pharmacology*; D000705:Anaphase; D000818:Animals; D015153:Blotting, Western; D002453:Cell Cycle; D002460:Cell Line; D002522:Chlorocebus aethiops; D002843:Chromatin / Q000187:drug effects / Q000648:ultrastructure*; D007668:Kidney; D008677:Metaphase; D008938:Mitosis; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors; D016160:Retinoblastoma Protein / Q000032:analysis / Q000302:isolation & purification / Q000378:metabolism*
D002843:Chromatin; D047428:Protein Kinase Inhibitors; D016160:Retinoblastoma Protein; D015075:2-Aminopurine