engleski

Identification of the multidrug resistance-associated protein (mrp) related gene in red mullet (Mullus barbatus)

Multixenobiotic resistance mechanism (MXR) in aquatic organisms is mediated by the activity of the P-glycoprotein (Pgp) that binds and actively effluxes different chemicals out of cell. Concerning characteristics and tissue distribution of non-P-glycoprotein transport proteins recently identified in different human and animal tissues we hypothesized that members of the multidrug resistance-associated protein (MRP) family may frequently be expressed in aquatic organisms. We tried to identify MRP related genes in different tissues of several marine and freshwater bivalve (Mytilus galloprovincialis, Dreissena polymorpha, Anodonta cygnea) and fish species (Mullus barbatus, Cyprinus carpio, Salmo trutta) in this study. Following an alignment of known MRP1 and MRP2 human sequences, as well as the available mrp2 sequences from animal tissues, we determined highly conserved regions and used them to design three pairs of consensus primers. Total RNA was isolated, reverse transcribed to cDNA and the obtained cDNAs were PCR amplified with the corresponding primers. The amplified PCR products were sequenced and their homology compared with Pgp and MRP protein sequences from different species. The expression of MRP related mRNA was clearly identified only in liver tissue isolated from red mullet, with homologies at the protein level ranging from 75 to 76%. Described results clearly pointed at the possibility that at least in fish species MXR as a general defense mechanism may be mediated by the activities of at least two different types of transport proteins.

multixenobiotic resistance (MXR) ; multidrug resistance-associated protein (MRP) ; bivalves ; fish

Rad je prezentiran na skupu Twelfth International Symposium on Pollutant Responses in Marine Organisms ; M.O. James (ur.).