InterPro domain: IPR010561

This entry represents protein LIN-9/ALWAYS EARLY (LIN-9/ALY). LIN-9 from Caenorhabditis elegans is a homologue of the Drosophila always early (ALY) protein, which functions as a repressor of cell cycle regulated genes [ 1 , 2 ].

LIN-9 is a component of the evolutionary conserved DREAM (MuvB/DRM) complex, which represses transcription [ 3 ]. DREAM complex undergoes a cell cycle dependent switch of subunits. DREAM core binds to the E2F4 transcription factor and to the RBL2 (p130) in quiescent cells, while associates with the transcription factor B-MYB in the S-phase [ 4 ]. In humans, LIN-9 acts as a tumor suppressor and plays a role in the expression of genes required for the G1/S transition [ 4 , 5 ]. In pluripotent embryonic stem cells (ESC), LIN-9 plays an important role for proliferation and genome stability by activating genes with important functions in mitosis and cytokinesis [ 6 ].

In Arabidopsis thaliana, ALY is expressed ubiquitously in vegetative and reproductive tissues [ 6 ].

1. LIN9, a subunit of the DREAM complex, regulates mitotic gene expression and proliferation of embryonic stem cells. PLoS ONE 8, e62882
2. Gene structure and molecular analysis of Arabidopsis thaliana ALWAYS EARLY homologs. Gene 336, 219-29
3. Some C. elegans class B synthetic multivulva proteins encode a conserved LIN-35 Rb-containing complex distinct from a NuRD-like complex. Proc. Natl. Acad. Sci. U.S.A. 103, 16782-7
4. Inhibition of oncogenic transformation by mammalian Lin-9, a pRB-associated protein. EMBO J. 23, 4627-38
5. A mutant allele of BARA/LIN-9 rescues the cdk4-/- phenotype by releasing the repression on E2F-regulated genes. Exp. Cell Res. 312, 2465-75
6. A philosophy of dental practice. Int J Prosthodont 5, 291