Yingjamsiri P.Paca-Uccaralertkun S.Mahidol University2023-11-272023-11-272023-10-01ScienceAsia Vol.49 No.5 (2023) , 760-76415131874https://repository.li.mahidol.ac.th/handle/20.500.14594/91211Inhibitor of differentiation 1 (ID1) protein is highly expressed in undifferentiated cells and associated with tumor progression and metastasis. Restricted regulation of the gene expression is necessary for cell maintenance. We performed the characterization of the response elements involved in the regulation of ID1 promoter activity using deletions and mutations. In silico analysis was used to predict regulatory binding sites. Mutants of the 5' upstream region of the ID1 promoter were constructed with nucleotide deletion or mutation, and the promoter activity was systematically analyzed. In silico analysis revealed several transcription binding sites presented in upstream region of the ID1 gene. Cluster of four Sp1 binding sites at position -1296 to -1078 contributed to the maximal expression activity of ID1 gene. The deletion and mutation of these Sp1 binding sites resulted in reduction of the expression level. Moreover, it is suggested that mutation of the Sp1 binding site at position -1078 could permit repressor proteins to suppress the gene expression. This study yields a new insight to a better understanding of the ID1 gene regulation, which pave the way to obtain the normal expression level of ID1 for cancer therapy development.MultidisciplinaryArticleSCOPUS10.2306/scienceasia1513-1874.2023.0792-s2.0-85176943853