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Fig. 4 Mouse TRIM71 recognizes mRNA UTRs of other cell-cycle related genes. (a) Sequences and predicted secondary structures of RNA fragments deduced from UTRs of Cdkn1a, Rbl2 and Dbn1. (b) EMSA results of mTRIM71-NHL bound to RNA fragments of Trincr1, Cdkn1a-3′UTR, Cdkn1a-5′UTR, Rbl2-3′UTR and Dbn1-3′UTR. The predicted stem-loop RNA of Cdkn1a-3′UTR exhibits strong in vitro interactions with mTRIM71-NHL. (c) EMSA results of RNA fragments of Cdkn1a-3′UTR and Rbl2-3′UTR bound to mTRIM71-NHL and mutants. R642A, K659A and Y689A mutants severely weakened the RNA-protein recognition. (d) RIP-qPCR results of mESCs expressing wild-type, R642A, K659A and Y689A mutants of mTRIM71 with FLAG. Data were first normalized to the corresponding input and then to ESCs transfected with 3 × FLAG-GFP control. Enrichment of Cdkn1a and Rbl2 were observed, whereas Dbn1 was not evidently enriched. Malat1 was introduced as negative control. Values are means ± standard deviation (SD). n = 3 independent experiments. (****) P < 0.0001.