CGC Bibliography Paper 5298

C. elegans class B synthetic multivulva genes act in G1 regulation.

Boxem M, van den Heuvel S

Medline:

12062054

Citation:

Current Biology 12: 906-911 2002

Type:

ARTICLE

Genes:

cdk-4 chd-3 cki-1 cki-2 cyd-1 dpl-1 efl-1 efl-2 egl-27 egr-1 hda-1 let-418 lin-8 lin-9 lin -15 lin-35 lin-36 lin-37 lin-38 lin-53 tam-1

Abstract:

The single C. elegans member of the retinoblastoma gene family, lin-35 Rb, was originally identified as a synthetic Multivulva (synMuv) gene [1]. These genes form two redundant classes, A and B, that repress ectopic vulval cell fate induction [2, 3]. Recently, we demonstrated that lin-35 Rb also acts as a negative regulator of G(1) progression and likely is the major target of cyd-1 Cyclin D and cdk-4 CDK4/6 [4]. Here,we describe G(1) control functions for several other class B synMuv genes. We found that efl-1 E2F negatively regulates cell cycle entry, while dpl-1 DP appeared to act both as a positive and negative regulator. In addition, we identified a negative G(1) regulatory function for lin-9 ALY, as well as lin-15B and lin-36, which encode novel proteins. Inactivation of lin-35 Rb, efl-1, or lin-36 allowed S phase entry in the absence of cyd-1/cdk-4 and increased ectopic cell division when combined with cki-1 Cip/Kip RNAi. These data are consistent with lin-35 Rb, efl-1, and lin-36 acting in a common pathway or complex that negatively regulates G(1) progression. In contrast, lin-15B appeared to act in parallel to lin-35. Our results demonstrate the potential for genetic identification of novel G(1) regulators in C.