Target Background
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],caution:Was originally (PubMed:11278651) thought to bind to the palindromic consensus sequence 5'-TCCCAGCACTTTGGGA-3' and to regulate the transcription of numerous genes in the lung.,disease:Defects in TOPORS are the cause of retinitis pigmentosa type 31 (RP31) [MIM:609923]. RP leads to degeneration of retinal photoreceptor cells. Patients typically have night vision blindness and loss of midperipheral visual field. As their condition progresses, they lose their far peripheral visual field and eventually central vision as well. RP31 inheritance is autosomal dominant.,function:Functions as an ubiquitin-protein E3 ligase and as an E3 SUMO1-protein ligase. Can both ubiquitinate and sumoylate p53.,induction:By genotoxic agents such as cisplatin and camptothecin.,PTM:Sumoylated.,similarity:Contains 1 RING-type zinc finger.,subcellular location:Localizes to discrete nuclear foci which partly overlap with PML nuclear bodies.,subunit:Interacts with PARK7/DJ-1 (By similarity). Interacts with TOP1. Interacts with p53. Interacts with the SUMO1 conjugating enzyme UBE2I. Interacts with SUMO1.,tissue specificity: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.,
