microRNA expression in bone marrow cells from Gfi1 deficient mice

Growth factor independent-1 (Gfi1) is a zinc finger transcription factor with a SNAG amino-terminal repressor domain and is critically required for normal myelopoesis. Gfi1 is normally expressed in HSCs and induced during differentiation from CMPs to GMPs. Gfi1 loss-of-function mutation in mice and humans induces an arrest during myeloid differentiation and an absolute block to the formation mature neutrophils. This comparative microarray study was initiated to identify microRNAs which are potentially regulated by Gfi1 during granulopoiesis. The Gfi1 null allele from Orkin (deletion of exons 2 and 3) was backcrossed to B6 or Balb/c mice for at least 7 generations. RNA was isolated from low density bone marrow samples from Gfi1+/+ and Gfi1-/- B6 littermates, as well as Gfi1+/+ and Gfi1-/- Balb/c littermates.