Analysis of gene expression profiles in primary embryonic fibroblasts deficient for the Ing1 locus

The ING familiy of tumor suppressor proteins control several cellular functions relevant to anti-tumor protection, like cell-cycle control, apoptosis, senescence or migration. ING proteins are functionally linked to the p53 pathway, and they participate in transcriptional control via the recognition of histone marks and recruitment of protein complexes with chromatin-modifying activity to specific promoters. Here, we have investigated the global impact of ING1 in gene regulation through genome-wide analysis of expression profiles in primary embryonic fibroblasts deficient for the Ing1 locus. We find that Ing1 has a predominant role as transcriptional repressor in this setting, affecting the expression of genes involved in a variety of cellular functions. Within the subset of genes showing differential expression, we have identified DGCR8, a protein involved in the early steps of microRNA biogenesis. In this study we have taken an unbiased approach to identify Ing1 targets, consisting in the comparison of expression profiles by genome-wide microarray analysis (Codelink mouse whole-genome expression microarrays), of mouse embryonic fibroblasts from embryos with the Ing1 locus inactivated by the insertion of a gene trap cassette, and their wild-type littermates. Three biological replicates were done for each phenotype.