High impact information on UHRF2

• The polypeptide assignments to the mtDNA URFs analyzed here are supported by the relative electrophoretic mobilities of proteins 11, 4-5, 26, and 1, which are those expected for the molecular weights predicted from the DNA sequence for the products of URF2, URF4, URF4L, and URF5, respectively [1].
• In particular, antibodies directed against the NH2-terminal octapeptide of the putative URF2 product specifically precipitated component 11 of the HeLa cell mitochondrial translation products, the reaction being inhibited by the specific peptide [1].
• In the human mitochondrial DNA we have found a DNA curvature structure within the 3'-region of ther URF2 sequence in front of the L-strand origin of replication [2].
• Considering that NIRF is implicated in cell cycle regulation, these findings suggest that NIRF and PCNP are a ubiquitin ligase and its substrate, respectively, and may constitute a novel signaling pathway with some relation to cell proliferation [3].
• PCNP was readily ubiquitinated in 293 and COS-7 cells, and NIRF ubiquitinated PCNP in vitro as well as in vivo [3].

Biological context of UHRF2

• NIRF, a novel RING finger protein, is involved in cell-cycle regulation [4].
• Flow cytometric analysis showed that overexpression of NIRF induced an increase in G1 phase cells [5].
• URF2, encoding an Mr 13600 protein which lies within the i-leader region, is not well conserved in either nucleotide or amino acid sequence [6].
• We identified one mitochondrial gene, coding for subunit 1 of cytochrome oxidase, which is overexpressed in infected tissues whereas another mitochondrial gene, URF 2, is not [7].

Physical interactions of UHRF2

• There existed phosphorylated NIRF in cells, and dephosphorylated NIRF interacted with Cdk2 [5].

Enzymatic interactions of UHRF2

• NIRF was phosphorylated by Cdk2 in vitro [5].

Other interactions of UHRF2

• 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 [4].
• NIRF induces G1 arrest and associates with Cdk2 [5].
• Immunoprecipitation and immunoblotting experiments showed that NIRF bound to the inactive Cdk2-cyclin E complex [5].
• NIRF is a RING finger protein with a ubiquitin-like domain, a PHD finger, a YDG/SRA domain, and a RING finger domain [5].

Analytical, diagnostic and therapeutic context of UHRF2

• 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 [4].

References