Research note: Identification and characterization of SLC11A1 gene promoter of chicken.

SLC11A1 is a key gene involved in the regulation of innate immunity, and its expression level is closely associated with disease resistance in livestock and poultry, making it an important candidate gene for disease-resistant breeding. The functional characteristics of the promoter region are central to deciphering the transcriptional regulatory mechanisms of a gene. In this study, we focused on the chicken SLC11A1 gene and retrieved sequences flanking the transcription start site (TSS) from the NCBI database. By integrating bioinformatic analysis with a dual-luciferase reporter assay system, we systematically identified the core promoter region and functionally characterized the regulatory roles of cis-regulatory element and their associated transcription factor binding profiles. Results revealed a canonical TATA-box element located at -31 bp to -28 bp upstream of the TSS of the chicken SLC11A1 gene. Functional analysis using a series of truncated luciferase reporter constructs demonstrated that the region from -172 bp to +19 bp constitutes the core promoter of the chicken SLC11A1 gene, with the segment from -172 bp to -36 bp being essential for basal transcriptional activity, the TATA-box was shown to synergistically enhance transcriptional efficiency when combined with this region. Prediction of transcription factor binding sites indicated that Sp1 exhibited the highest binding frequency within the core promoter, followed by C/EBPalpha and other factors. These findings define the fundamental regulatory architecture of the chicken SLC11A1 promoter, providing essential insights for future studies on the transcriptional regulation and biological functions of SLC11A1.