MicroRNA-939 regulating CD2 -associated protein expression by targeting promoter / 中华实用儿科临床杂志

ABSTRACT

Objective To verify the targeting regulatory relationship between microRNA -939 (miR -939) and CD2 -associated protein (CD2AP).Methods The online RegRNA software was used to predict the human CD2AP promoter for potential binding sites complementary to miR -939.HEK -293T cells were cotransfected with hu-man CD2AP promoter plasmid pGL3 -2K and microRNA negative control (miR -NC)or miR -939 mimics,and the relative luciferase activity(RLA)was detected at 24 h post -transfection.HEK -293T cells were transfected with miR -NC or miR -939 mimics for 48 h,and the CD2AP mRNA expression level was detected by adopting reverse tran-script and real -time fluorescence quantification -PCR,while the CD2AP protein expression level was detected by using Western blot.Results (1 )There were 2 miR -939 binding sites at CD2AP promoter region,located at -468 to -491 and -654 to -677 upstream of initiation codon ATG (marked as +1 )relatively.(2)At 30 nmol/L,50 nmol/L,the RLA in miR -NC group and miR -939 group were 6.81 ±0.88 vs 6.07 ±2.24,5.88 ±1 .44 vs 3.94 ± 0.79 relatively,and there were no significant differences between the 2 groups (t =3.04,2.06,all P >0.05),while the RLA between the 2 groups were 5.58 ±0.58 vs 3.29 ±0.64 at 1 00 nmol/L,and the difference was significant between the 2 groups(t =4.07,P <0.05).(3)At 30 nmol/L,50 nmol/L and 100 nmol/L,the relative CD2AP mRNA expression in miR -NC group and miR -939 group were 1 .00 ±0.01 vs 0.80 ±0.08,1 .00 ±0.00 vs 0.80 ±0.1 3 and 1 .00 ± 0.00 vs 0.72 ±0.07 relatively,while the CD2AP mRNA expression was decreased by 20% -30% at each concentration level,and there were significant differences between the 2 groups (t =4.44,2.93,6.84,all P <0.05).(4)At 50 nmol/L, the relative CD2AP protein expression in miR -NC group and miR -939 group were 0.48 ±0.09 vs 0.19 ±0.12,and the CD2AP protein expression was decreased,and the difference was significant (t =3.36,P <0.05).Conclusions CD2AP is the target gene of miR -939,and miR -939 can down -regulate the expression of CD2AP both in mRNA and protein levels by targeting its promoter region,which indicates that miR -939 may mediate the podocyte injury.