NIRF, a novel RING finger protein, is involved in cell-cycle regulation

Biochem Biophys Res Commun. 2002 Aug 23;296(3):530-6. doi: 10.1016/s0006-291x(02)00890-2.


Through database mining, we found a novel PEST-containing nuclear protein (PCNP). To characterize PCNP, we carried out yeast two-hybrid screening for PCNP-interacting factors. A novel Np95/ICBP90-like RING finger protein (NIRF), which possessed a ubiquitin-like domain, a PHD finger, a YDG/SRA domain and a RING finger, was identified. Interaction between PCNP and NIRF was clarified by mammalian two-hybrid system, GST pull-down assay, and nuclear co-localization. RT-PCR showed that NIRF expression is high in proliferating phase but significantly low in G0/G1 phase in normal TIG-7 and WI-38 cells, while consistently high in tumoral HT-1080 and HepG2 cells, suggesting that NIRF is involved in cell-cycle regulation. The NIRF gene resides in 9p23-24.1 that is altered in numerous types of tumors at the top of frequency. Furthermore, the NIRF gene is just within small amplicons in some tumors, suggesting that PCNP and NIRF might be involved in some aspects of tumorigenesis.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Amino Acid Sequence
  • Animals
  • COS Cells
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Cycle
  • Cell Division
  • Cell Line
  • Chromosome Mapping
  • Cloning, Molecular
  • Humans
  • Molecular Sequence Data
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / metabolism*
  • Nuclear Proteins / physiology*
  • Protein Structure, Tertiary
  • RNA, Messenger / biosynthesis
  • Sequence Alignment
  • Tumor Cells, Cultured
  • Ubiquitin-Protein Ligases*


  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • Nuclear Proteins
  • PCNP protein, human
  • RNA, Messenger
  • UHRF2 protein, human
  • Ubiquitin-Protein Ligases

Associated data

  • GENBANK/AB037675
  • GENBANK/AB071698