Identification of DNA methylation and transcriptional regulatory regions in the promoter of duck retinoic acid inducible gene I (RIG-I).

1. The aim of this study was to identify the active control area of the duck retinoic acid-inducible gene I (duRIG-I) core promoter, to predict the binding sites of transcription factors and to provide a theoretical basis for the study of duRIG-I function and mechanism of regulation. 2. The promoter region of duRIG-I was obtained from Ensembl; the CpG island in the duRIG-I promoter was predicted online; and the methylation status of the duRIG-I promoter was detected by the bisulphite sequencing PCR method. 3. There was an obvious CpG island in the duRIG-I promoter, with a total of 44 CG dinucleotides. However, the level of methylation was hypomethylation (0.2%). 4. The core transcriptional regulatory region was identified, localised between -301 and ~+14 bp, where multiple transcription factor binding sites including IRF1, RXRβ, AP-2αA, RAP1, NF-1 and SP1 motifs were identified that significantly enhanced RIG-I promoter activity.