An Entamoeba histolytica Rab-like encoding gene and protein: function and cellular location

• Published in: Molecular and biochemical parasitology 2000-05, Vol.108 (2), p.199-206
• Main Authors: Rodrı́guez, Mario Alberto, Garcı́a-Pérez, Rosa Marı́a, Garcı́a-Rivera, Guillermina, López-Reyes, Israel, Mendoza, Leobardo, Ortiz-Navarrete, Vianney, Orozco, Esther
• Format: Article
• Language: English
• Subjects: Amino Acid Motifs; Amino Acid Sequence; Animals; Antibodies, Protozoan; Biological Transport; Blotting, Northern; Blotting, Western; Cell Membrane - metabolism; Cytoplasm - metabolism; EhrabB gene; Entamoeba histolytica; Entamoeba histolytica - genetics; Entamoeba histolytica - metabolism; Genes, Protozoan; Guanosine Diphosphate - metabolism; Guanosine Triphosphate - metabolism; Microscopy, Confocal; Molecular Sequence Data; Phagocytosis; Protein traffic; Rab; rab GTP-Binding Proteins - chemistry; rab GTP-Binding Proteins - genetics; rab GTP-Binding Proteins - immunology; rab GTP-Binding Proteins - metabolism; Rab protein; Recombinant Proteins - immunology; Transcription, Genetic
• ISSN: 0166-6851; 1872-9428
• DOI: 10.1016/S0166-6851(00)00216-4

We identified here a 576 bp rab-like gene ( EhrabB) in Entamoeba histolytica. EhrabB is located 332 bp upstream from the start codon of the Ehcp112 encoding gene, but is transcribed from the complementary strand. The EhrabB open reading frame predicts a 192 amino acid polypeptide ( EhRabB) with 40–42% identity to Rab proteins, involved in vesicle docking regulation in endo and exocytic pathways of eukaryotic cells. Transcripts of 0.6 and 0.97 kb were detected by the EhrabB probe in northern blot assays. Using specific antibodies, EhRabB was located in small cytoplasmic vesicles by confocal microscopy. During phagocytosis, EhRabB was initially translocated to the plasma membrane and to the phagocytic mouths. The protein diminished after 10 min phagocytosis, suggesting that EhRabB could be participating in the regulation of the endocytosis process.