Transcriptional regulation of human USP24 gene expression by NF-kappa B
JOURNAL OF NEUROCHEMISTRY
Authors: Wang, Ke; Liu, Shengchun; Wang, Juelu; Wu, Yili; Cai, Fang; Song, Weihong
Abstract
Impairment of the ubiquitin proteasome pathway is believed to play an important role in the pathogenesis of Parkinson's disease. This process is carried out under tight regulation by deubiquitinating enzymes. Genetic linkage studies indicated that the region of the human ubiquitin-specific protease 24 (USP24) gene is significantly correlated with Parkinson's disease. In this study, we cloned a 1648 bp 5 flanking region of the human USP24 gene coding sequence and a series of nested deletions into the pGL3-Basic vector. We analyzed promoter activities of these regions with a luciferase-based reporter assay system. A 64-bp region was identified to contain the transcription initiation site and a minimum promoter sequence for transcriptional activation of the USP24 gene expression. Expression of USP24 is controlled by a TATA-box-less promoter with several putative cis-acting elements. Transcriptional activation and gel-shift assay demonstrated that the USP24 gene promoter contains a functional NF kappa B-binding site. Over-expression of nuclear factor kappa-light-chain-enhancer of activated B cells (NF kappa B) and tumor-necrosis factor alpha (TNF alpha) treatment significantly increased the USP24 promoter activity, mRNA expression and protein level in human HEK293 cells, mouse N2a cells and human neuroblastoma SH-SY5Y cells. Deletion and mutation of the binding site abolished the regulatory effect of NF kappa B on human USP24 gene transcription. These results suggested that USP24 expression is tightly regulated at its transcription level and NF kappa B plays an important role in this process.
Involvement of USP24 in the DNA damage response
MOLECULAR & CELLULAR ONCOLOGY
Authors: Zhang, Ling; Gong, Feng
Abstract
Deubiquitination has emerged as an important mechanism of regulating DNA repair pathways. We recently reported that USP24 is a novel p53 deubiquitinase that stabilizes p53 upon DNA damage. USP24 is upregulated by DNA damaging agents and plays an important role in maintaining genome stability.