TOPORS Antibody – Mouse Monoclonal

This gene encodes a nuclear protein which is serine and arginine rich, and contains a RING-type zinc finger domain. It is highly expressed in the testis, and functions as an ubiquitin-protein E3 ligase. Mutations in this gene are associated with retinitis pigmentosa type 31. Alternatively spliced transcript variants, encoding different isoforms, have been observed for this locus. [provided by RefSeq, Sep 2010]

TOPORS: Functions as an E3 ubiquitin-protein ligase and as an E3 SUMO1-protein ligase. Probable tumor suppressor involved in cell growth, cell proliferation and apoptosis that regulates p53/TP53 stability through ubiquitin-dependent degradation. May regulate chromatin modification through sumoylation of several chromatin modification-associated proteins. May be involved in DNA damage- induced cell death through IKBKE sumoylation. Interacts with PARK7/DJ-1. Interacts with TOP1. Interacts with p53/TP53; can both ubiquitinate and sumoylate p53/TP53. Interacts with the SUMO1 conjugating enzyme UBE2I. Interacts with SUMO1. Interacts with NKX3-1; polyubiquitinates NKX3-1 and induces its proteasomal degradation. Interacts with SIN3A; sumoylates SIN3A. Interacts with IKBKE; induced by DNA damage. By genotoxic agents such as cisplatin and camptothecin. Expressed at highest levels in testis and at lower levels in adrenal gland, bone marrow, brain, colon, heart, kidney, liver, muscle, ovary, pancreas, placenta, prostate, skeletal muscle, skin, small intestine, spleen, stomach, testis, thymus, thyroid and uterus. Expressed in the alveolar epithelium of the lung. Expression is commonly decreased in colon adenocarcinomas and lung cancers. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 6.3.2.-; Ligase; Ubiquitin ligase; Cell cycle regulation; Ubiquitin conjugating system; EC 6.3.2.19

Chromosomal Location of Human Ortholog: 9p21

Cellular Component: centriole; spindle pole; PML body; cytoplasmic dynein complex; nuclear speck; midbody; nucleus; photoreceptor connecting cilium; ubiquitin ligase complex; gamma-tubulin complex

Molecular Function: protein binding; DNA binding; zinc ion binding; ubiquitin-protein ligase activity; SUMO ligase activity; antigen binding; ligase activity

Biological Process: ubiquitin-dependent protein catabolic process; protein monoubiquitination; proteasomal ubiquitin-dependent protein catabolic process; retinal rod cell development; transcription, DNA-dependent; positive regulation of transcription, DNA-dependent; regulation of cell proliferation; protein sumoylation; retinal cone cell development; DNA damage response, signal transduction resulting in induction of apoptosis; positive regulation of ubiquitin-protein ligase activity; maintenance of protein localization in nucleus; response to DNA damage stimulus; DNA damage response, signal transduction by p53 class mediator resulting in induction of apoptosis; negative regulation of apoptosis

Disease: Retinitis Pigmentosa 31