RNA cytosine-5-methyltransferase NSUN1 (NSUN1)

RNA cytosine-5-methyltransferase NSUN1, also known as NOP2 or p120, is a nucleolar protein essential for ribosome biogenesis and cell proliferation (UniProt P33759). It specifically catalyzes the site-specific 5-methylcytosine (m5C) modification of 28S ribosomal RNA (rRNA), which is crucial for proper rRNA processing and the assembly of the large ribosomal subunit (PubMed: 28418038). NSUN1 is frequently overexpressed in a wide variety of human cancers, including breast, lung, and liver cancers, where its levels often correlate with tumor grade and poor prognosis (PubMed: 31439631). As a key regulator of the cell cycle, it promotes the transition from G1 to S phase and is often used as a marker of proliferating cells (PubMed: 10438494). While there are currently no FDA-approved drugs specifically targeting NSUN1, it is considered an attractive therapeutic target in oncology because its inhibition can lead to nucleolar stress, cell cycle arrest, and apoptosis in malignant cells (PubMed: 33806154). Additionally, NSUN1 has been implicated in the regulation of viral replication, such as HIV-1, by modifying viral RNA or host translational machinery (PubMed: 28418038).

Other names

NOP2NOL1p120Nucleolar protein 120Nucleolar antigen p120NOP2 nucleolar protein

Inhibition of RNA cytosine-5-methyltransferase activity or downregulation of protein expression to disrupt ribosome biogenesis and cell proliferation.