Identification of RALY as a novel regulator of DSCR1 transcription.

Down syndrome critical region 1 (DSCR1) is located on chromosome 21, whose N-terminal coding sequence lacks recognizable motifs, and its precise transcriptional and translational regulation remains incompletely understood. Utilizing a bicistronic reporter system, we identified the core promoter region of DSCR1, which enables investigation of its gene regulatory mechanisms. Proteomic analyses via LC-MS/MS revealed that RALY directly binds to the DSCR1 promoter, influencing its transcriptional activity. Notably, RALY overexpression markedly suppresses DSCR1 expression, whereas siRNA-mediated knockdown of RALY does not significantly alter DSCR1 levels, suggesting complex regulatory dynamics. Given DSCR1's vital roles in Down syndrome (DS) phenotypes and critical biological processes such as neuronal development and immune regulation, modulation of RALY-mediated transcription may represent a novel mechanism for maintaining cellular homeostasis.