MiR-486-5p-directed MAGI1/Rap1/RASSF5 signaling pathway contributes to hydroquinone-induced inhibition of erythroid differentiation in K562 cells.

Bone marrow failure is a characteristic effect of benzene exposure. Our previous study has shown that miR-486-5p is involved in benzene induced-suppression of erythroid differentiation. However, the mechanism of miR-486-5p to initiate the above process remains unclear. In this study, we used miRTar software to predict putative miRNA targets and pathway. We found that miR-486-5p may target Ras-associated protein-1 (Rap1) signaling pathway-associated genes. Our in vitro study further showed significant dose-dependent upregulation of MAGI1 and RASSF5 expressions in hydroquinone (HQ)-induced suppression of erythroid differentiation of K562 cells. Over-expression or down-regulation of miR-486-5p altered MAGI1 and RASSF5 expression and modified erythroid differentiation. Dual-luciferase reporter assay and fluorescence-based RNA electrophoresis mobility assay (FREMSA) further confirmed that miR-486-5p directly bound to the 3'-untranslated region (3'-UTR) of MAGI1 and RASSF5. In addition, the expressions of RAPGEF2 and RAP1A, which are downstream genes of MAGI1, were also significantly increased when HQ inhibited erythroid differentiation. Knockdown of MAGI1 reversed HQ-induced inhibition of erythroid differentiation via downregulation of RAPGEF2, RAP1A and RASSF5. Together, these data indicate that miR-486-5p directly targets MAGI1 and RASSF5 and integrates with Rap1 signaling to modify HQ-induced inhibition of erythroid differentiation in K562 cells.