Research article
Large-scale RNAi screens identify novel genes that interact with the C. elegans retinoblastoma pathway as well as splicing-related components with synMuv B activity
-
* Corresponding author: Sander van den Heuvel S.J.L.vandenheuvel@bio.uu.nl
1 Massachusetts General Hospital Cancer Center and Harvard Medical School, Building 149, 13th Street, Charlestown, 02129 MA, USA
2 Center for Cancer Systems Biology (CCSB) and Department of Cancer Biology, Dana-Farber Cancer Institute, and Department of Genetics, Harvard Medical School, 44 Binney Street, Boston, 02115 MA, USA
3 Department of Developmental Biology, Utrecht University, Kruytbuilding, Padualaan 8, 3584 CH Utrecht, The Netherlands
4 Present address : Molecular Oncology and Aging Research, Centre d'Investigacions en Bioquímica I Biología Molecular (CIBBIM), Hospital Universitari Vall d'Hebron 119-129, Barcelona 08035, Spain
BMC Developmental Biology 2007, 7:30 doi:10.1186/1471-213X-7-30
Published: 6 April 2007Abstract
Background
The retinoblastoma tumor suppressor (Rb) acts in a conserved pathway that is deregulated in most human cancers. Inactivation of the single Rb-related gene in Caenorhabditis elegans, lin-35, has only limited effects on viability and fertility, yet causes changes in cell-fate and cell-cycle regulation when combined with inactivation of specific other genes. For instance, lin-35 Rb is a synthetic multivulva (synMuv) class B gene, which causes a multivulva phenotype when inactivated simultaneously with a class A or C synMuv gene.
Results
We used the ORFeome RNAi library to identify genes that interact with C. elegans lin-35 Rb and identified 57 genes that showed synthetic or enhanced RNAi phenotypes in lin-35 mutants as compared to rrf-3 and eri-1 RNAi hypersensitive mutants. Based on characterizations of a deletion allele, the synthetic lin-35 interactor zfp-2 was found to suppress RNAi and to cooperate with lin-35 Rb in somatic gonad development. Interestingly, ten splicing-related genes were found to function similar to lin-35 Rb, as synMuv B genes that prevent inappropriate vulval induction. Partial inactivation of specific spliceosome components revealed further similarities with lin-35 Rb functions in cell-cycle control, transgene expression and restricted expression of germline granules.
Conclusion
We identified an extensive series of candidate lin-35 Rb interacting genes and validated zfp-2 as a novel lin-35 synthetic lethal gene. In addition, we observed a novel role for a subset of splicing components in lin-35 Rb-controlled processes. Our data support novel hypotheses about possibilities for anti-cancer therapies and multilevel regulation of gene expression.