Fig. 5.

circ_0030998 functioned as a miR‐558 sponge. (A) The circular interactome was utilized to predict the RBPs that may interact with circ_0030998, and eight proteins were predicted and exhibited. (B) A pull‐down assay was adopted to verify the interaction between circ_0030998 and the 8 proteins. (C) The miRNAs that may bind to circ_0030998 were also predicted through the circular interactome, and the regulatory relationships were confirmed by luciferase reporter assay. (D) Putative miR‐558 binding sequences in circ_0030998 are displayed, and reporter gene plasmids were constructed. (E) The luciferase intensity between circ_0030998 and miR‐558 was assessed through a dual‐luciferase reporter gene assay. (F,G) The enrichments of circ_0030998 and miR‐558 were also verified by RNA pull‐down assay in A549 cells. (H,I) Ago2‐IP assay was then applied to confirm the enrichments of circ_0030998 and miR‐558 in A549 cells. Data represent the mean ± SD from three independent experiments. Student’s t‐test with two biological dependent or independent replicates was used to determine statistical significance; *P < 0.05, **P < 0.01, ***P < 0.001