[Role of p38alpha kinase in activation of premature senescence program in transformed mouse fibroblasts].
We investigated the role of p38alpha stress-kinase in regulation of premature senescence program, stimulated by histone deacetylase inhibitor--sodium butyrate (NaB)--after application to rodent transformed cell lines. Investigation was performed on the E1A + cHa-ras transformants selected from mice embryonic fibroblasts null at the p38alpha kinase gene or null fibroblasts at the PPM1D gene, which encoded phosphatase Wip1. Absence of Wip1 led to constitutive activation of p38alpha kinase. It was revealed that after NaB treatment both cell lines completely stopped proliferation due to irreversible cell cycle arrest in G1/S phase. In both cell lines sodium butyrate induced sustained block of prolifaration due to irreversible cell cycle arrest in G1/S phase. Following sodium butyrate treatment cells expressed marker of senescence--beta-galactosidase activity (SA-beta-Gal). Long-term (during several days) NaB treatment of cells led to partial restoration of actin cytoskeleton, focal adhesion contacts and heterochromatin focus formation (SAHF) in the nucleus of senescent cells. Obtained data allow us to suppose that irreversible process of cellular senescence activated by sodium butyrate can occur in the absence of functionally active p38 kinase by means of other ways of cell cycle suppression.
Zubova
S G
SG
Bykova
T V
TV
Zubova
Iu G
IuG
Romanov
V S
VS
Aksenov
N D
ND
Pospelov
V A
VA
Pospelova
T V
TV
D000818:Animals; D002087:Butyrates / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000502:physiology*; D050881:E1A-Associated p300 Protein / Q000235:genetics / Q000378:metabolism; D004622:Embryo, Mammalian; D005347:Fibroblasts / Q000502:physiology; D017353:Gene Deletion; D011905:Genes, ras / Q000235:genetics; D056572:Histone Deacetylase Inhibitors; D051379:Mice; D048308:Mitogen-Activated Protein Kinase 14 / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D009363:Neoplasm Proteins / Q000172:deficiency / Q000235:genetics; D010749:Phosphoprotein Phosphatases / Q000172:deficiency / Q000235:genetics; D000071636:Protein Phosphatase 2C; D014170:Transformation, Genetic; D001616:beta-Galactosidase / Q000378:metabolism
D002087:Butyrates; D056572:Histone Deacetylase Inhibitors; D009363:Neoplasm Proteins; D050881:E1A-Associated p300 Protein; D048308:Mitogen-Activated Protein Kinase 14; D010749:Phosphoprotein Phosphatases; C000607468:Ppm1d protein, mouse; D000071636:Protein Phosphatase 2C; D001616:beta-Galactosidase