Upregulation Of MiR-3648 Upon ER Stress And Its Regulatory Role In Cell Proliferation

MicroRNAs(miRNAs)are small non coding RNAs that modulate the stability of their target mRNA and/or the translational potential of their mRNA targets.They respond accordingly to the cell environment and can promote either cell survival or cell death.miRNAs play important roles under multiple cellular conditions including endoplasmic reticulum(ER)stress.We found that miR-3648,a human specific microRNA,was induced under ER stress.We also found that miR-3648 was upregulated at transcriptional level.Moreover,we used luciferase assay to find a true target of miR-3648.Out of 13 predicted targets,Adenomatous polyposis coli 2(APC2),a tumor suppressor and a negative regulator of Wnt signaling,was found to be the direct target of miR-3648.Levels of APC2 were down regulated when cells were under ER stress or after overexpressing miR-3648.Inhibition of miR-3648 by antagomir increased APC2 levels and decreased the cell proliferation.Conversely,when miR-3648 was overexpressed,APC2 levels were decreased and the cell growth increased.The present study about miR-3648 and APC2 added a novel link between ER stress and Wnt/? catenin signaling in human cells.Our data demonstrated that miR-3648 was induced at transcriptional level upon ER stress in human cells,which then down regulated APC2 to increase cell proliferation.