| Description | 1531 amino acids, 190 kDa; contains two ATP binding domains and three membrane-spanning helices; member of the ATP-binding cassette proteins (ABC proteins). |
| Expression | expressed at a basal level in a wide variety of normal tissues, including epithelial cells and all hematopoietic cell types, which suggests a function common to most cell types; increased expression in various tumor cell type. |
| Localisation | in normal cells, predominant localisation in the cytoplasm; in tumor cells, predominant in plasma membrane, but also found in endoplasmic reticulum, indicating a probable different function as in normal cells. |
| Function | plasma membrane drug-efflux pump; MRP induces a multidrug resistance phenotype (MDR phenotype); overexpression confers tumor cell resistance to a wide variety of hydrophobic drugs: doxorubicin, daunorubicin, vinblastine, vincristine, colchicine, VP16, Rhodamin 123; glutathione is required for the effective expulsion of the chemotherapeutic agents; the mode of action of MRP is very similar to the one of P-glycoprotein, the main protein responsible for the MDR phenotype; however, MRP does not confer resistance to Taxol or m-AMSA, but it is able to transport metallic oxyanions, glutathione and other glutathione conjugates; inhibitors of organic anion transport, such as probenecid, can block MRP activity. |
| Homology | structural and/or functional homology with other ABC transporter proteins (CFTR, Pgp, MOAT). |
| Overexpression of a transporter gene in a multidrug-resistant human lung cancer cell line. |
| Cole SP, Bhardwaj G, Gerlach JH, Mackie JE, Grant CE, Almquist KC, Stewart AJ, Kurz EU, Duncan AM, Deeley RG |
| Science (New York, N.Y.). 1992 ; 258 (5088) : 1650-1654. |
| PMID 1360704 |
| |
| Expression of the multidrug resistance-associated protein (MRP) in acute and chronic leukemias. |
| Burger H, Nooter K, Zaman GJ, Sonneveld P, van Wingerden KE, Oostrum RG, Stoter G |
| Leukemia : official journal of the Leukemia Society of America, Leukemia Research Fund, U.K. 1994 ; 8 (6) : 990-997. |
| PMID 7911548 |
| |
| The human multidrug resistance-associated protein MRP is a plasma membrane drug-efflux pump. |
| Zaman GJ, Flens MJ, van Leusden MR, de Haas M, Mˆºlder HS, Lankelma J, Pinedo HM, Scheper RJ, Baas F, Broxterman HJ |
| Proceedings of the National Academy of Sciences of the United States of America. 1994 ; 91 (19) : 8822-8826. |
| PMID 7916458 |
| |
| Multidrug resistance-associated protein: a protein distinct from P-glycoprotein involved in cytotoxic drug expulsion. |
| Barrand MA, Bagrij T, Neo SY |
| General pharmacology. 1997 ; 28 (5) : 639-645. |
| PMID 9184795 |
| |
| Function, evolution and structure of multidrug resistance protein (MRP). |
| Deeley RG, Cole SP |
| Seminars in cancer biology. 1997 ; 8 (3) : 193-204. |
| PMID 9441948 |
| |
| Multidrug resistance: molecular mechanisms and clinical relevance. |
| Ling V |
| Cancer chemotherapy and pharmacology. 1997 ; 40 Suppl : S3-S8. |
| PMID 9272126 |
| |
| The role of multidrug resistance-associated protein (MRP) expression in multidrug resistance. |
| Kavallaris M |
| Anti-cancer drugs. 1997 ; 8 (1) : 17-25. |
| PMID 9147606 |
| |
| The prognostic significance of the expression and function of multidrug resistance transporter proteins in acute myeloid leukemia: studies of the Southwest Oncology Group Leukemia Research Program. |
| Willman CL |
| Seminars in hematology. 1997 ; 34 (4 Suppl 5) : 25-33. |
| PMID 9408958 |
| |