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Differential pre-mRNA processing in Crebbp+/- mice

ABSTRACT: The presence of unspliced transcripts in hematopoietic stem cells (HSCs) and the proposed association of CREBBP with the constitutive production of unspliced RNA and with pre-mRNA processing prompted us to examine more closely an anomaly we had noted in microarray-based gene expression studies but had previously attributed to experimental noise. We noticed that more than half of the probe sets down-regulated in Crebbp+/- fetal liver HSCs (FLHSCs) relative to wild-type (WT) mapped entirely within introns, rather than detecting exonic or spliced sequences. We therefore set out to test whether this might be evidence that reduced CREBBP levels selectively alter the generation of full-length, unspliced pre-mRNA. We also asked whether this process might be associated with differentiation since self-renewal and lineage commitment are the both responses for which HSCs are primed. Total RNA from wild-type, Crebbp+/-, Ep300+/-, Cdkn1a-/- FLHSCs and from wild type and Crebbp+/- mouse embryonic fibroblasts (MEFs) was isolated and hybridized to Affymetrix Mouse 430 2.0 expression microarrays. Fetal liver HSC RNA was amplified using the Ovation kit prior to hybridization. cell type comparison

ORGANISM(S): Mus musculus

SUBMITTER: Madeleine Lemieux

PROVIDER: E-GEOD-27987 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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