Characterization of a Rab11 homologue in Trypanosoma cruzi.
Vesicle trafficking between organelles occurs through fusion of donor and specific acceptor membranes. This process is highly regulated and ensures proper direction in sorting and packaging of a number of molecules in eukaryotic cells. Monomeric GTPases of the Rab family play a pivotal role in the control of membrane fusion and vesicle traffic. In this paper, we characterize a Trypanosoma cruzi Rab 11 homologue (TcRab11) that shares at, the amino acid level, 40% similarity with human rab11, Arabdopsis thaliana rab11 and yeast rab11 homologue genes. Western blot analysis, using a polyclonal rabbit antiserum raised against a synthetic peptide derived from the COOH-terminus of predicted the TcRab11 protein, reacted to a 26kDa protein. In immunofluorescence assays, TcRab 11, was shown to be expressed in epimastigote and amastigote forms, but it was absent in trypomastigotes. Interestingly, the TcRab11 product seems to be located at the reservosome complex, a site of active endocytosis and vesicle fusion present only in the epimastigote stage. Therefore, TcRab11 may represent the first molecular marker of this peculiar organelle.
Mauricio de Mendonca
S M
SM
Laboratorio de Parasitologia Molecular, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Nepomuceno da Silva
J L
JL
Cunha e-Silva
N
N
de Souza
W
W
Gazos Lopes
U
U
D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D005455:Fluorescent Antibody Technique; D018507:Gene Expression Regulation, Developmental; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014349:Trypanosoma cruzi / Q000235:genetics* / Q000254:growth & development; D020691:rab GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D000099193:rab11 GTP-Binding Proteins
D016054:DNA, Protozoan; D012333:RNA, Messenger; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins