Expression data from murine hematopoietic stem cells

Long-term hematopoietic output is dependent on the hematopoietic stem cell (HSC) homeostasis which is maintained by a complex network of molecules. Among these, microRNAs (miRNAs) play crucial roles, while the underlying molecular basis have not been fully demonstrated. Here, we found that miR-21 is enriched in murine HSCs. Then, we generated a polyinosinic:polycytidylic acid (pIpC)-inducible mouse model (miR-21flox/flox:Mx1-Cre) to obtain a specific deletion of miR-21 in hematopoietic system. It was found that mice with conditional knockout of miR-21 exhibit an obvious perturbation of normal hematopoiesis.Further researches reveal that miR-21 deficiency affect HSC homeostasis and function. We used microarrays to detail the global programme of gene expression, and identified distinct classes of up-regulated and down-regulated genes in murine HSCs after miR-21 conditional knockout. We have found that miR-21 deficiency affects the homeostasis and function of hematopoietic stem cells (HSCs). To explore the underlying molecular mechanisms, we sorted Lineage- c-Kit+ Sca1+ cells (LSKs) that are highly enriched with HSCs from the bone marrow of pIpC-injected miR-21 conditional knockout mice (miR-21flox/flox:Mx1-Cre+) and littermate control mice (miR-21flox/flox:Mx1-Cre-) by flow cytometry. Each group had three replicate samples. Then, these samples were used for RNA extraction and hybridization on Affymetrix microarrays.