title: Identification of members of the P-glycoprotein multigene family.
abstract: Overproduction of P-glycoprotein is intimately associated with multidrug resistance. This protein appears to be encoded by a multigene family. Thus, differential expression of different members of this family may contribute to the complexity of the multidrug resistance phenotype. Three lambda genomic clones isolated from a hamster genomic library represent different members of the hamster P-glycoprotein gene family. Using a highly conserved exon probe, we found that the hamster P-glycoprotein gene family consists of three genes. We also found that the P-glycoprotein gene family consists of three genes in mice but has only two genes in humans and rhesus monkeys. The hamster P-glycoprotein genes have similar exon-intron organizations within the 3' region encoding the cytoplasmic domains. We propose that the hamster P-glycoprotein gene family arose from gene duplication. The hamster pgp1 and pgp2 genes appear to be more closely related to each other than either gene is to the pgp3 gene. We speculate that the hamster pgp1 and pgp2 genes arose from a recent gene duplication event and that primates did not undergo this duplication and therefore contain only two P-glycoprotein genes.
authors.affiliation: Ontario Cancer Institute, Canada.
authors.forename: W F
authors.initials: WF
authors.lastname: Ng
authors.forename: F
authors.initials: F
authors.lastname: Sarangi
authors.forename: R L
authors.initials: RL
authors.lastname: Zastawny
authors.forename: L
authors.initials: L
authors.lastname: Veinot-Drebot
authors.forename: V
authors.initials: V
authors.lastname: Ling
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D006224:Cricetinae; D004247:DNA / Q000235:genetics; D015342:DNA Probes; D004351:Drug Resistance / Q000235:genetics; D005091:Exons; D006801:Humans; D007438:Introns; D008562:Membrane Glycoproteins / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D013045:Species Specificity
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D015342:DNA Probes; D008562:Membrane Glycoproteins; D004247:DNA