Unknown,Transcriptomics,Genomics,Proteomics

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Differential gene expression profiles between myeloid-biased and lymphoid-biased hematopoietic stem cells.

ABSTRACT: Array analysis of My-bi and Ly-bi HSC identifies candidate molecules for myeloid-bias. Collectively the data show that HSC in adults are largely epigenetically fixed in differentiation and self-renewal behavior. A direct examination of the epigenetic mechanisms that imprint HSC is difficult. However, an indirect way of assessing the effects of epigenetic imprinting is to look for the expressed gene programs of different types of HSC. Therefore, we performed an array analysis in collaboration with Dr. Michael Cooke. My-bi and Ly-bi HSC were identified in clonally repopulated hosts. The analysis returned 218 differentially expressed genes (M-bM-^IM-% Log2 M-bM-^IM-%2, p< 0.05) of which 36 were found to be overexpressed in My-bi HSC and the rest was overexpressed in Ly-bi HSC (Appendix A). There was no difference in expression levels for genes known to be involved in fate decisions during differentiation. This agrees well with our data that lineage bias is a stable function of a HSC, and does not reflect a differentiated type of cell. Gene expression profiles of myeloid-biased (My-bi) and lymphoid-biased (Ly-bi) stem cells were analyzed. Clonally repopulated hosts were generated by limiting dilution of bone marrow into ablated hosts and lineage bias was determined. Single My-bi (Tenor) and Ly-bi (Mort) repopulated hosts were sacrificed and Donor type HSC were enriched for Sca-1+, Lin- cells. Two technical replicates of RNA extract were run from each clone.

ORGANISM(S): Mus musculus

SUBMITTER: Hans Sieburg

PROVIDER: E-GEOD-41702 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Differential gene expression profiles between myeloid-biased and lymphoid-biased hematopoietic stem cells.

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