MiR-144 Regulates Hemoglobin Expression in Human Erythroid Cell Line

Abstract

The regulation of globin gene expression is significantly important to understand the pathogenesis of globin gene disorders. Recent findings have shown that microRNAs (miRNAs, miRs) play an important role in the regulation of globin gene expression. The miR-144 is an erythroid lineage-specific miRNA, in which its expression mediates NRF2 gene silencing and inhibits fetal hemoglobin expression. However, roles of miR-144 to other globin genes expression especially in ɑ-globin cluster remain unknown. This study, thus, examined the functional studies of miR-144 to globin gene expression in K562 human erythroid cell line. The results revealed that ɑ-globin and z-globin gene expression were silenced by the overexpressed miR-144 and that correlated with the reduced expression of KLF1- the suspected target gene. By contrast, transfection with miR-144 inhibitor reversed the silencing effect of miR-144. On the other hand, miR-144 had no effect to β-globin gene expression. Our results sustain the findings of the previous studies that the overexpression of miR-144 correlates with the repressing of NRF2 and 𝛄-globin gene expression. Taken together, our results suggest that miR-144 plays a key role in globin gene expression by silencing 𝛄-globin through NRF2 target mRNA and repressing adult ɑ-globin and embryonic z-globin gene expression possibly by targeting KLF1 gene.