Figure 4.

Secisbp2l is able to promote translation of DIOs. A, SECIS elements of mouse Dios. Highly conserved nucleotides are indicated in bold. B, Enrichment of Dio2 and Dio3 mRNA by anti-SECISBP2L antibody by co-immunoprecipitation. Note that Ct values for Dio1 exceeded 35, indicating an extremely low expression of Dio1. Actb (β-actin) was used as a negative control. C, Scheme of SecCHECK with SECIS from Dio1, Dio2, and Dio3. Mutation of a TGC codon in firefly luciferase of siCHECK into TGA results in SecCHECK. D, SecCHECK with or without SECIS were co-transfect with control vector (pCDH), Secisbp2, full-length Secisbp2l or C-terminal Secisbp2l (CT-Secisbp2l) for luciferase activity assay. Overexpression of Secisbp2l and Secisbp2 increased firefly luciferase activity with SECIS, whereas CT-Secisbp2l had little effect. All values are represented as mean ± SD; *p < 0.05, **p < 0.01, ***p < 0.001; NS, not significant.