Precision mechanics with multifunctional tools: how hnRNP K and hnRNPs E1/E2 contribute to post-transcriptional control of gene expression in hematopoiesis.

Studies on the post-transcriptional control of gene expression in hematopoietic cells have uncovered that a subfamily of heterogeneous nuclear ribonucleoproteins (hnRNPs) is involved in cytoplasmic gene regulation. Among them hnRNP K and hnRNPs E1/E2 share common structural motifs, the hnRNP K homology (KH) domains that provide a functional basis for RNA binding. Specific sub-cellular localization and differentiation dependent post-translational modifications modulate the interaction of these proteins with mRNA and proteins in messenger ribonucleoprotein complexes (mRNPs), the latter generating connectivity to cell signaling events. As components of different mRNPs, hnRNP K and hnRNPs E1/E2 function as crucial modulators of mRNA stability and translation in hematopoietic cell differentiation.