|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Massachusetts General Hospital Cancer Center, Building 149, 13th Street, Charlestown, MA 02129, USA
*Author for correspondence (e-mail: heuvel{at}helix.mgh.harvard.edu)
Accepted August 1, 2001
We have investigated the regulation of cell-cycle entry in C. elegans, taking advantage of its largely invariant and completely described pattern of somatic cell divisions. In a genetic screen, we identified mutations in cyd-1 cyclin D and cdk-4 Cdk4/6. Recent results indicated that during Drosophila development, cyclin D-dependent kinases regulate cell growth rather than cell division. However, our data indicate that C. elegans cyd-1 primarily controls G1 progression. To investigate whether cyd-1 and cdk-4 solely act to overcome G1 inhibition by retinoblastoma family members, we constructed double mutants that completely eliminate the function of the retinoblastoma family and cyclin D-Cdk4/6 kinases. Inactivation of lin-35 Rb, the single Rb-related gene in C. elegans, substantially reduced the DNA replication and cell-division defects in cyd-1 and cdk-4 mutant animals. These results demonstrate that lin-35 Rb is an important negative regulator of G1/S progression and probably a downstream target for cyd-1 and cdk-4. However, as the suppression by lin-35 Rb is not complete, cyd-1 and cdk-4 probably have additional targets. An additional level of control over G1 progression is provided by Cip/Kip kinase inhibitors. We demonstrate that lin-35 Rb and cki-1 Cip/Kip contribute non-overlapping levels of G1/S inhibition in C. elegans. Surprisingly, loss of cki-1, but not lin-35, results in precocious entry into S phase. We suggest that a rate limiting role for cki-1 Cip/Kip rather than lin-35 Rb explains the lack of cell-cycle phenotype of lin-35 mutant animals.
Key words: C. elegans, Cyclin, CDK, pRb, Cip/Kip, Cell cycle
This article has been cited by other articles:
![]() |
C. Schertel and B. Conradt C. elegans orthologs of components of the RB tumor suppressor complex have distinct pro-apoptotic functions Development, October 15, 2007; 134(20): 3691 - 3701. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. W. Reddien, E. C. Andersen, M. C. Huang, and H. R. Horvitz DPL-1 DP, LIN-35 Rb and EFL-1 E2F Act With the MCD-1 Zinc-Finger Protein to Promote Programmed Cell Death in Caenorhabditis elegans Genetics, April 1, 2007; 175(4): 1719 - 1733. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Chesney, A. R. Kidd III, and J. Kimble gon-14 Functions With Class B and Class C Synthetic Multivulva Genes to Control Larval Growth in Caenorhabditis elegans Genetics, February 1, 2006; 172(2): 915 - 928. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Grishok and P. A. Sharp Negative regulation of nuclear divisions in Caenorhabditis elegans by retinoblastoma and RNA interference-related genes PNAS, November 29, 2005; 102(48): 17360 - 17365. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Nimmo, A. Antebi, and A. Woollard mab-2 encodes RNT-1, a C. elegans Runx homologue essential for controlling cell proliferation in a stem cell-like developmental lineage Development, November 15, 2005; 132(22): 5043 - 5054. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. M. Davison, M. M. Harrison, A. J. M. Walhout, M. Vidal, and H. R. Horvitz lin-8, Which Antagonizes Caenorhabditis elegans Ras-Mediated Vulval Induction, Encodes a Novel Nuclear Protein That Interacts With the LIN-35 Rb Protein Genetics, November 1, 2005; 171(3): 1017 - 1031. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Yochem, L. R. Bell, and R. K. Herman The Identities of sym-2, sym-3 and sym-4, Three Genes That Are Synthetically Lethal With mec-8 in Caenorhabditis elegans Genetics, November 1, 2004; 168(3): 1293 - 1306. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Emmerich, C. A. Meyer, A. F. A. de la Cruz, B. A. Edgar, and C. F. Lehner Cyclin D Does Not Provide Essential Cdk4-Independent Functions in Drosophila Genetics, October 1, 2004; 168(2): 867 - 875. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Garbe, J. B. Doto, and M. V. Sundaram Caenorhabditis elegans lin-35/Rb, efl-1/E2F and Other Synthetic Multivulva Genes Negatively Regulate the Anaphase-Promoting Complex Gene mat-3/APC8 Genetics, June 1, 2004; 167(2): 663 - 672. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. S. Fay, E. Large, M. Han, and M. Darland lin-35/Rb and ubc-18, an E2 ubiquitin-conjugating enzyme, function redundantly to control pharyngeal morphogenesis in C. elegans Development, July 15, 2003; 130(14): 3319 - 3330. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. H. Thomas, C. J. Ceol, H. T. Schwartz, and H. R. Horvitz New Genes That Interact With lin-35 Rb to Negatively Regulate the let-60 ras Pathway in Caenorhabditis elegans Genetics, May 1, 2003; 164(1): 135 - 151. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. C. Shakes, P. L. Sadler, J. M. Schumacher, M. Abdolrasulnia, and A. Golden Developmental defects observed in hypomorphic anaphase-promoting complex mutants are linked to cell cycle abnormalities Development, April 15, 2003; 130(8): 1605 - 1620. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. S. Fay, S. Keenan, and M. Han fzr-1 and lin-35/Rb function redundantly to control cell proliferation in C. elegans as revealed by a nonbiased synthetic screen Genes & Dev., February 15, 2002; 16(4): 503 - 517. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Kostic and R. Roy Organ-specific cell division abnormalities caused by mutation in a general cell cycle regulator in C. elegans Development, January 5, 2002; 129(9): 2155 - 2165. [Abstract] [Full Text] [PDF] |
||||