Alternative titles; symbols
HGNC Approved Gene Symbol: RCHY1
Cytogenetic location: 4q21.1 Genomic coordinates (GRCh38) : 4:75,479,033-75,514,715 (from NCBI)
Using the N terminus of the human androgen receptor (AR; 313700) as bait in a yeast 2-hybrid screen of a mouse neuroblastoma/spinal cord hybrid cell cDNA library, Beitel et al. (2002) cloned Znf363, which they designated Arnip. By database analysis and PCR, they cloned human ARNIP from a prostate carcinoma cDNA library. The deduced mouse and human proteins contain 261 amino acids. ARNIP contains a RING-H2 (C3H2C3) finger domain, which is capable of coordinating zinc ions, and several putative phosphorylation sites. ARNIP shares 90.4% amino acid identity with mouse Arnip and significant homology with Arnip from several other vertebrate and invertebrate species. All cysteine and histidine residues in the C3H2C3 RING motif are conserved between species. Northern blot analysis of mouse tissues detected a major transcript of about 1.7 kb expressed at highest levels in testis, at moderate levels in kidney, and at low levels in all other tissues examined. Expression was also detected in several mouse and human cell lines, some of which also expressed a minor transcript of about 1.3 kb.
Leng et al. (2003) cloned the mouse Znf363 gene, which they called Pirh2. Pirh2 encodes a RING-H2 domain-containing protein with 261 amino acids and a predicted molecular mass of 30 kD. The cysteine-rich RING motif is defined by a consensus sequence with 8 cysteines and histidines that coordinate 2 zinc ions. Northern blot analysis of various adult mouse tissues detected transcripts of 1.7 and 1.6 kb. Expression was highest in liver, followed by testis and heart. Lower levels were detected in muscle and spleen.
By yeast 2-hybrid analysis, Beitel et al. (2002) confirmed interaction between ARNIP and the N terminus of AR. Fluorescence-tagged mouse Arnip exhibited punctate cytoplasmic or perinuclear distribution following transfection into COS-1 cells. Cotransfection with human AR resulted in the redistribution of Arnip to match the distribution of AR in both the absence or the presence of a synthetic nonmetabolizable androgen. Interaction between AR and Arnip was hormone independent, and Arnip did not affect AR ligand-binding kinetics, nor did Arnip modulate AR in transactivation assays. However, the interaction between the N and C termini of AR was reduced in the presence of Arnip. The RING-H2 domain of Arnip also functioned as a ubiquitin-protein ligase in vitro in the presence of a specific ubiquitin-conjugating enzyme, Ubc4-1 (see 602962). Cys145-to-ala substitution in the RING-H2 domain abolished the ubiquitin ligase activity.
Leng et al. (2003) determined that the mouse Pirh2 gene is regulated by p53 (191170) and encodes a protein with intrinsic ubiquitin-protein ligase activity. Pirh2 was found to interact physically with p53 and to promote ubiquitination of p53 independently of Mdm2 (164785). Expression of Pirh2 decreased the level of p53 protein, while abrogation of endogenous Pirh2 expression increased the level of p53. Furthermore, Pirh2 repressed p53 functions, including p53-dependent transactivation and growth inhibition. Leng et al. (2003) concluded that Pirh2 is involved in the negative regulation of p53 function through physical interaction and ubiquitin-mediated proteolysis. Therefore, Pirh2, like Mdm2, participates in an autoregulatory feedback loop that controls p53 function.
Using yeast 2-hybrid analysis, protein pull-down assays, and coimmunoprecipitation analysis, Zhang et al. (2005) showed that human NTKLBP1 (GORAB; 607983) interacted directly with PRIH2. Mutation analysis revealed that the C-terminal coiled-coil domain of NTKLBP1 interacted with the N-terminal domain of PIRH2.
Beitel et al. (2002) determined that the ZNF363 gene contains 9 exons and spans 32 kb.
By genomic sequence analysis and FISH, Beitel et al. (2002) mapped the ZNF363 gene to chromosome 4q21.
Beitel, L. K., Elhaji, Y. A., Lumbroso, R., Wing, S. S., Panet-Raymond, V., Gottlieb, B., Pinsky, L., Trifiro, M. A. Cloning and characterization of an androgen receptor N-terminal-interacting protein with ubiquitin-protein ligase activity. J. Molec. Endocr. 29: 41-60, 2002. [PubMed: 12200228] [Full Text: https://doi.org/10.1677/jme.0.0290041]
Leng, R. P., Lin, Y., Ma, W., Wu, H., Lemmers, B., Chung, S., Parant, J. M., Lozano, G., Hakem, R., Benchimol, S. Pirh2, a p53-induced ubiquitin-protein ligase, promotes p53 degradation. Cell 112: 779-791, 2003. [PubMed: 12654245] [Full Text: https://doi.org/10.1016/s0092-8674(03)00193-4]
Zhang, L., Li, J., Wang, C., Ma, Y., Huo, K. A new human gene hNTKL-BP1 interacts with hPirh2. Biochem. Biophys. Res. Commun. 330: 293-297, 2005. [PubMed: 15781263] [Full Text: https://doi.org/10.1016/j.bbrc.2005.02.156]