title: Functional consequences of RNA interference targeting COMMD1 in a canine hepatic cell line in relation to copper toxicosis.
abstract: A deletion in the copper metabolism (Murr1) domain containing 1 (COMMD1) gene is associated with hepatic copper toxicosis in dogs, yet evidence of copper retention in COMMD1-depleted hepatic cells has not been shown. In a dog hepatic cell line, we analysed the copper metabolic functions after an 80% (mRNA and protein) COMMD1 reduction with COMMD1-targeting siRNAs. Exposure to 64Cu resulted in a significant increase in copper retention in COMMD1-depleted cells. COMMD1-depleted cells were almost three times more sensitive to high extracellular copper concentrations. Copper-mediated regulation of metallothionein gene expression was enhanced in COMMD1-depleted cells. Based on the increased copper accumulation and enhanced cellular copper responses upon COMMD1 reduction, we conclude that COMMD1 has a major regulatory function for intracellular copper levels in hepatic cells.
authors.affiliation: Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands. b.spee@vet.uu.nl
authors.forename: B
authors.initials: B
authors.lastname: Spee
authors.forename: B
authors.initials: B
authors.lastname: Arends
authors.forename: A M T C
authors.initials: AM
authors.lastname: van Wees
authors.forename: P
authors.initials: P
authors.lastname: Bode
authors.forename: L C
authors.initials: LC
authors.lastname: Penning
authors.forename: J
authors.initials: J
authors.lastname: Rothuizen
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003300:Copper / Q000378:metabolism*; D004285:Dogs; D005786:Gene Expression Regulation / Q000235:genetics*; D008099:Liver / Q000166:cytology* / Q000378:metabolism; D008668:Metallothionein / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C480519:COMMD1 protein, human; D002352:Carrier Proteins; D034741:RNA, Small Interfering; D003300:Copper; D008668:Metallothionein