Dataset Information

Differential expression between FHL2-/- and WT MEFs.

ABSTRACT: The LIM-only protein FHL2 acts as a transcriptional modulator that positively or negatively regulates multiple signaling pathways. We recently reported that FHL2 cooperates with CBP/p300 in the activation of ß-catenin/TCF target gene cyclin D1. In this paper, we demonstrate that FHL2 is associated with the cyclin D1 promoter at the TCF/CRE site, providing evidence that cyclin D1 is a direct target of FHL2. We show that deficiency of FHL2 greatly reduces the proliferative capacity of spontaneously immortalized mouse fibroblasts which is associated with decreased expression of cyclin D1 and p16INK4a, and hypophosphorylation of Rb. Reexpression of FHL2 in FHL2-null fibroblasts efficiently restores cyclin D1 levels and cell proliferative capacity, indicating that FHL2 is critical for cyclin D1 activation and cell growth. Moreover, ectopic cyclin D1 expression is sufficient to override growth inhibition of immortalized FHL2-null fibroblasts. Gene expression profiling revealed that FHL2 deficiency triggers a broad change of the cell cycle program that is associated with downregulation of several G1/S and G2/M cyclins, E2F transcription factors and DNA replication machinery, thus correlating with reduced cell proliferation. This change also involves downregulation of the negative cell cycle regulators, particularly INK4 inhibitors, which could counteract the decreased expression of cyclins, allowing cells to grow. Our study illustrates that FHL2 can act on different aspects of the cell cycle program to finely regulate cell proliferation. Keywords: mouse embryonic fibroblasts derived from FHL2-/- and WT mouse embryos (14.5 days)

ORGANISM(S): Mus musculus

PROVIDER: GSE10902 | GEO | 2008/06/06

SECONDARY ACCESSION(S): PRJNA107309

REPOSITORIES: GEO

ACCESS DATA

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Project description:Cyclin D1 belongs to the core cell cycle machinery1, and it is frequently overexpressed in human cancers2. The full repertoire of cyclin D1 functions in normal development and in cancer cells is currently unknown. To address this question, here we introduce a novel approach that allows one to determine the set of cyclin D1-interacting proteins (D1 âinteractomeâ) and cyclin D1-bound genomic fragments (D1 âcistromeâ) in essentially any mouse organ, at any point of development or at any stage of cancer progression. Using this approach, we detected several novel tissue-specific interactors of cyclin D1. A significant number of these partners represent proteins involved in transcription. We show, using genome-wide location analysis3, that cyclin D1 occupies promoters of a very large number of genes in the developing mouse, where it binds in close proximity to transcription start sites. Bioinformatics analyses of cyclin D1-bound genomic segments in the developing embryo revealed DNA recognition sequences for several transcription factors. By querying SAGE libraries4, promoter CpG content5 and gene expression profiles of cyclin D1-null organs, we demonstrate that cyclin D1 binds promoters of highly expressed genes, and that it functions to activate or to repress gene expression in vivo. Analyses of cyclin D1 transcriptional targets reveal that cyclin D1 contributes to cell proliferation by upregulating genes required for S-phase entry and progression. Hence, cyclin D1 plays a broad transcriptional regulatory function in vivo during normal mouse development. We wished to determine whether cyclin D1 functioned to positively or negatively regulate transcription of the target genes (identified by chip-on-chip) in vivo. To address this question, we asked how expression of cyclin D1-bound genes changes when cyclin D1 has been knocked-out. We dissected retinas from eyes of cyclin D1-/- or wild-type neonates, isolated RNA and hybridized it onto Affymetrix expression arrays.

Dataset Information

Differential expression between FHL2-/- and WT MEFs.

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets