Identification of the promoter region regulating the transcription of the REV7 gene

• Published in: Biochemical and biophysical research communications 2023-06, Vol.662, p.8-17
• Main Authors: Shimada, Yuko, Kato, Takuya, Sakurai, Yasutaka, Watanabe, Hitoe, Nonaka, Mayu, Nanaura, Natsumi, Ichinoe, Masaaki, Murakumo, Yoshiki
• Format: Article
• Language: English
• Subjects: Animals; BLIMP-1; Cyclic AMP Response Element-Binding Protein - metabolism; HEK293 Cells; Humans; Luciferases - metabolism; Mammals - metabolism; Promoter region; Promoter Regions, Genetic; Repressor Proteins - metabolism; REV7; Transcription factor
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2023.04.056

REV7 is involved in various biological processes including DNA repair and mutagenesis, cell cycle regulation, gene transcription, and carcinogenesis. REV7 is highly expressed in adult testicular germ cells as well as several malignant tumors. REV7 expression levels are associated with prognosis in several human cancers, however, the mechanism of REV7 transcriptional regulation has not been elucidated. In this study, we characterized the promoter region of the REV7 gene. A luciferase reporter assay using the human germ cell tumor cell line NEC8 was utilized to examine the upstream genomic region of REV7 for transcriptional activity, and two transcriptional activation regions were identified. We determined a small genomic region important for transcriptional activation using site-directed mutagenesis; this region is shared by several putative binding motifs for transcription factors, including the cAMP-responsive element modulator (CREM), cAMP-response element binding protein (CREB), and B-lymphocyte-induced maturation protein-1 (BLIMP-1). Exogenous CREM and CREB expression had no effect on the transcriptional activity in NEC8 cells or the human embryonic kidney cell line HEK293T. In contrast, exogenous BLIMP-1 expression increased luciferase reporter activity in HEK293T cells but unexpectedly decreased activity in NEC8 cells. Chromatin immunoprecipitation analysis demonstrated that BLIMP-1 binds to the genomic region near the binding motif in the REV7 promoter. Additionally, BLIMP-1 overexpression promoted endogenous REV7 expression in HEK293T cells. These findings suggest that BLIMP-1 may be a putative transcriptional regulator of REV7 in mammalian cells. •We identified two regions for transcriptional activation in the REV7 promoter region.•BLIMP-1 affects the transcriptional activity of the REV7 promoter region.•BLIMP1 binds to the REV7 promoter region and affects endogenous REV7 expression.•BLIMP-1 may be a putative transcriptional regulator of REV7 in mammalian cells.