Molecular characterization and expression analysis of a P-glycoprotein homologue in Toxoplasma gondii.
ATP-binding cassette (ABC) transporters represent an important family of membrane proteins involved in drug resistance and other biological activities. The present study reports on the characterization of a P-glycoprotein (Pgp), TgABC.B1, in the protozoan parasite Toxoplasma gondii. The protein encoded by the TgABC.B1 gene displays the typical (TMD-NBD)2 structural organization of the "full" ABC transporter and shows significant identity and similarity with two apicomplexan Pgps; Pgh1 in Plasmodium falciparum and CpABC3 in Cryptosporidium parvum. The TgABC.B1 gene is a single copy gene transcribed into a full-length mRNA of 4.3kb and expressed as a protein of approximately 150kDa, which cellular localization revealed a membrane-associated labelling in tachyzoites. The TgABC.B1 gene is constitutively expressed in the three major T. gondii genotypes but demonstrated a higher expression in virulent type I, at both transcriptional and translational levels. Further characterization of this Pgp-like protein will increase our knowledge of the membrane transport system in this parasite and could result in the identification of a new therapeutic target in Toxoplasma.
Schmid
Aline
A
Laboratoire de Parasitologie-Mycologie, EA 3800, IFR 53, UFR Médecine, Université de Reims Champagne-Ardenne, 51 rue Cognacq-Jay, 51095 Reims cedex, France.
Sauvage
Virginie
V
Escotte-Binet
Sandie
S
Aubert
Dominique
D
Terryn
Christine
C
Garnotel
Roselyne
R
Villena
Isabelle
I
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D005260:Female; D015870:Gene Expression; D006801:Humans; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D008970:Molecular Weight; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016415:Sequence Alignment; D014122:Toxoplasma / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014123:Toxoplasmosis / Q000469:parasitology*
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D015800:Protozoan Proteins