Target regulation of miR-9 to the expression of NRP1 and its role in radiation effects / 中华放射医学与防护杂志

ABSTRACT

Objective To explore the effect of miR-9 on the expression of NRP1 and its radiation effects in A549 cells.Methods Bioinformatics was used to analyze the potential binding sites of has-miR-9 and NRP1-3'UTR.The miR-9 sequence was inserted into pcDNA-DEST-47 plasmid to construct the eukaryotic expression vector (pcDNA-DEST-miR-9) and to construct the NRP1 gene 3'UTR luciferase reporter plasmid (pEZX-MT05) at the same time.They were simultaneously transferred into A549 cells for analysis of the regulatory effect of miR-9 on the expression of NRP1.Meanwhile miR-29b was used as a negative control to observe whether or not NRP1 gene was a target of miR-9.After 10 Gy irradiation,the expression of NRP1,and the inhibitory effect of miR-9 on it was confirmed by Western blot assay.The expression of miR-9 was detected by real-time PCR.Results It was found that miR-9 reduced the luciferase activity of NRP1-3'UTR wild plasmid (t =3.906,P ＜ 0.05) but not NRP1-3' UTR mutant plasmid.This luciferase activity was not inhibited by other types of miRNA (miR-29b).The expression of NRP1 protein in A549 cells was decreased after the cells were transfected with miR-9 mimic.After irradiation with dose of 10 Gy,the expression of miR-9 were decreased (t =37.319,P ＜ 0.05) and the expression of NRP1 protein were increased.Conclusions miR-9 regulates the expression of NRP1 by targeting 3'UTR site of NRP1 gene in A549 cells.