Fig. 6

circZNF609 mediates the regulation of RAC1 mRNA stability by binding to FMRP. a Venn diagram showed potential downstream mRNA targets of FMRP. b and c RIP assays showed the association of FMRP with RAC1 mRNA in HMY-1 cells (b) and A875 cells (c). d and e The co-localization of FMRP protein and RAC1 mRNA in HMY-1 cells (d) and A875 cells (e) by immunofluorescence and FISH. f and g In acral melanoma cells (f) and cutaneous melanoma cells (g) transfected with FMRP siRNAs, the levels of RAC1 mRNA (top) were assessed by qRT–PCR analysis, and the levels of RAC1 protein (bottom) were assessed by western blot analysis. h The correlation between FMRP mRNA and RAC1 mRNA in Liang’s acral melanoma cohort from the cBioPortal database. i and j RAC1 mRNA stability was assessed after transfection with FMRP siRNA (i) or circZNF609 siRNA (j). k The expression of circZNF609 and RAC1 mRNA binding to FMRP were assessed after transfection with circZNF609 siRNA. l and m In acral melanoma cells (l) and cutaneous melanoma cells (m) transfected with circZNF609 siRNAs or circZNF609 vector, the levels of RAC1 mRNA (top) were assessed by qRT–PCR analysis, and the levels of RAC1 protein (bottom) were assessed by western blot analysis