Fig. 6
From: SUMO1 modification of KHSRP regulates tumorigenesis by preventing the TL-G-Rich miRNA biogenesis
SUMO1 modification of KHSRP interferes its interaction with pri-miRNAs. a Pri-miRNAs whose mature miRNAs were upregulated by KHSRP-K87R were analyzed by using the RNAstructure software. All of pri-let-7e, pri-let-7g, pri-let-7i, pri-miR-98 and pri-miR-182 harbored G-rich stretches in their terminal loops, as like pri-let-7a-1 and pri-let-7a-3. b KHSRPΔN fusing with SUMO1 decreases its interaction with pri-let-7a-1 and the mature let-7a production. 293T cells transfected CD513B-pri-let-7a-1 and Flag-KHSRPΔN, or Flag-SUMO1-KHSRPΔN were lysed for RIP with anti-Flag antibody, then treated with Trizol, and followed by qRT-PCR for pri-let-7a-1. The relative recruitment fold of pri-let-7a-1 by KHSRP was normalized with total pri-let-7a-1 in 293T cells (left panel). The expression level of mature let-7a was analyzed by qRT-PCR (middle panel) and the immunoprecipitation efficiency was assessed by Western blotting (right panel). c-d The SUMO-site mutation K87R of KHSRP increases its interaction with pri-let-7a-1 or pri-let-7a-3 and mature miRNA production. 293 T cells transfected with CD513B-pri-let-7a-1 (c) or CD513B-pri-let-7a-3 (d) and Flag-KHSRP-WT or Flag-KHSRP-K87R were lysed for RIP with anti-Flag antibody, and then treated with Trizol, followed by qRT-PCR for pri-let-7a-1 or pri-let-7a-3. The relative recruitment fold of pri-let-7a-1 or pri-let-7a-3 by KHSRP was normalized (left panel). The expression levels of mature let-7a were analyzed by qRT-PCR (right panel) and the immunoprecipitation efficiency was assessed by Western blotting (bottom panel)