|
|
||||||||
GROWTH, DIFFERENTIATION, AND APOPTOSIS
-DNA-binding activity during 3T3-L1 adipogenesis
Department of Nutrition, University of North Carolina School of Public Health, Chapel Hill, North Carolina 27599
Submitted 18 June 2003 ; accepted in final form 9 October 2003
Two pathways are initiated upon 3T3-L1 preadipocyte differentiation: the reentry of cells into the cell cycle and the initiation of a cascade of transcriptional events that "prime" the cell for differentiation. The "priming" event involves the synthesis of members of the CCAAT/enhancer binding protein (C/EBP) family of transcription factors. However, the relationship between these two pathways is unknown. Here we report that in the 3T3-L1 preadipocytes induced to differentiate, cell cycle progression and the initiation of differentiation are linked by a cell cycle-dependent Rb-C/EBP
interaction. Cell cycle arrest in G1 by L-mimosine inhibited differentiation-induced C/EBP
-DNA-binding activity and Rb phosphorylation. However, cell cycle arrest after the G1/S transition by aphidicolin or nocodazole did not prevent C/EBP
-DNA-binding activity or Rb phosphorylation. Furthermore, hypophosphorylated Rb and C/EBP
coimmunoprecipitated, whereas phosphorylated Rb and C/EBP
did not. Electrophoretic mobility shift assays demonstrated that recombinant hypophosphorylated Rb decreased C/EBP
-DNA-binding activity and that Rb overexpression inhibited C/EBP
-induced transcriptional activation of a C/EBP
-promoter-luciferase reporter gene. We conclude that C/EBP
-DNA-binding activity is regulated by its interaction with hypophosphorylated Rb, thereby linking the progression of the cell cycle to the initiation of differentiation during 3T3-L1 adipogenesis.
cell cycle regulation; cellular proliferation; differentiation
This article has been cited by other articles:
![]() |
O. Bezy, C. Vernochet, S. Gesta, S. R. Farmer, and C. R. Kahn TRB3 Blocks Adipocyte Differentiation through the Inhibition of C/EBP{beta} Transcriptional Activity Mol. Cell. Biol., October 1, 2007; 27(19): 6818 - 6831. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. V. Broers, F. C. S. Ramaekers, G. Bonne, R. B. Yaou, and C. J. Hutchison Nuclear lamins: laminopathies and their role in premature ageing. Physiol Rev, July 1, 2006; 86(3): 967 - 1008. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. J. Rochford, R. K. Semple, M. Laudes, K. B. Boyle, C. Christodoulides, C. Mulligan, C. J. Lelliott, S. Schinner, D. Hadaschik, M. Mahadevan, et al. ETO/MTG8 Is an Inhibitor of C/EBP{beta} Activity and a Regulator of Early Adipogenesis Mol. Cell. Biol., November 15, 2004; 24(22): 9863 - 9872. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |