Utilizing AntagomiR (Antisense microRNA) to Knock Down microRNA in Murine Bone Marrow Cells

MicroRNAs (miRNAs) are highly conserved small RNAs which regulate gene expression primarily through base pairing to the 3′ untranslated region of target messenger RNA (mRNA), leading to mRNA degradation or translation inhibition depending on the complementarity between the miRNA and target mRNA. Single miRNA regulates multiple target mRNA. miRNAs have been shown to regulate gene expression in the hematopoietic stem cells, as well as at key decision points for various lineages. However, aberrant expression of miRNAs has been documented in cancer and disease models. Rigorous dissection of miRNA pathways and biology requires facile loss of function modeling. This chapter describes detailed protocol for knockdown miRNA-21 which is involved in myelopoiesis using antagomiRs in primary murine bone marrow stem/progenitor cells.