The overexpression of a new ABC transporter in Leishmania is related to phospholipid trafficking and reduced infectivity.
This paper reports the characterization of a new ABC transporter (LtrABC1.1), related to the human ABCA subfamily, in the protozoan parasite Leishmania tropica. LtrABC1.1 is a tandem duplicated gene flanked by inverted repeats. LtrABC1.1 is expressed mainly in the flagellar pocket of the parasite. Drug resistance studies in Leishmania overexpressing LtrABC1.1 showed the transporter not to confer resistance to a range of unrelated drugs. LtrABC1.1 appears to be involved in lipid movements across the plasma membrane of the parasite since overexpression reduces the accumulation of fluorescent phospholipid analogues. The activity of this protein may also affect membrane movement processes since secreted acid phosphatase (SAP) activity was significantly lower in promastigotes overexpressing LtrABC1.1. In vitro infection experiments with macrophages indicated LtrABC1.1-transfected parasites to be significantly less infective. Together, these results suggest that this new ABC transporter could play a role in lipid movements across the plasma membrane, and that its activity might influence vesicle trafficking. This is the first ABCA-like transporter described in unicellular eukaryotes.
Parodi-Talice
Adriana
A
Instituto de Parasitología y Biomedicina López-Neyra, Consejo Superior de Investigaciones Científicas, c/Ventanilla 11, Granada 18001, Spain.
Araújo
Jose María
JM
Torres
Cristina
C
Pérez-Victoria
Jose María
JM
Gamarro
Francisco
F
Castanys
Santiago
S
D018528:ATP-Binding Cassette Transporters / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001692:Biological Transport; D006801:Humans; D007150:Immunohistochemistry; D018314:Leishmania infantum / Q000378:metabolism*; D007895:Leishmania tropica / Q000378:metabolism*; D008969:Molecular Sequence Data; D010743:Phospholipids / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism
D018528:ATP-Binding Cassette Transporters; D010743:Phospholipids; D012333:RNA, Messenger