title: Cell adhesion to substratum and activation of tyrosine kinases are essentially required for G1/S phase transition in BALB/c 3T3 fibroblasts.
abstract: Cell adhesion to substratum and activation of tyrosine kinases are essential for the progression of cell cycle through G1 phase in mammalian cells. The kinetic studies of mouse BALB/c 3T3 fibroblasts showed that serum was no longer required for the progression of G1/S phase transition. In contrast, cell adhesion was essentially required in late G1 phase, especially at the period of G1/S transition. Among the kinase inhibitors used to elucidate the signal transduction caused by cell adhesion, tyrosine kinase inhibitors, genistein and herbimycin A, blocked the G1/S transition most effectively when cells were exposed to the inhibitors at the period of G1/S transition. Cell adhesion was not critically required for cells to undergo DNA synthesis once they had passed the G1/S boundary, and the effects of tyrosine kinase inhibitors on the progression of S phase were also not critical. The expressions of histone H2B and dihydrofolate reductase (DHFR) genes (S phase specific genes) and also the transcription factor E2F-1 gene (an activator of DHFR gene) were suppressed when cells were cultured without adhesion or exposed to the tyrosine kinase inhibitors. These results suggest that cell adhesion to substratum plays an important role in the G1/S phase transition of mouse BALB/c 3T3 fibroblasts through the activation of tyrosine kinases other than growth factor receptor-tyrosine kinases.
authors.affiliation: Department of Biochemistry, Yamagata University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kuzumaki
authors.forename: A
authors.initials: A
authors.lastname: Matsuda
authors.forename: K
authors.initials: K
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Ishikawa
mesh_terms: D016475:3T3 Cells / Q000166:cytology*; D000818:Animals; D016227:Benzoquinones; D002352:Carrier Proteins; D002448:Cell Adhesion; D002453:Cell Cycle; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein; D006133:Growth Substances / Q000502:physiology; D006657:Histones / Q000378:metabolism; D007529:Isoflavones / Q000494:pharmacology; D047029:Lactams, Macrocyclic; D051379:Mice; D008807:Mice, Inbred BALB C; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011809:Quinones / Q000494:pharmacology; D056465:Retinoblastoma-Binding Protein 1; D017828:Rifabutin / Q000031:analogs & derivatives; D013762:Tetrahydrofolate Dehydrogenase / Q000378:metabolism; D050680:Transcription Factor DP1; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C533431:Arid4a protein, mouse; D016227:Benzoquinones; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D050687:E2F1 Transcription Factor; C493754:E2f1 protein, mouse; D004791:Enzyme Inhibitors; D006133:Growth Substances; D006657:Histones; D007529:Isoflavones; D047029:Lactams, Macrocyclic; D011809:Quinones; D056465:Retinoblastoma-Binding Protein 1; D050680:Transcription Factor DP1; D014157:Transcription Factors; D017828:Rifabutin; C020754:herbimycin; D019833:Genistein; D013762:Tetrahydrofolate Dehydrogenase; D011505:Protein-Tyrosine Kinases