title: Hemoglobin endocytosis in Leishmania is mediated through a 46-kDa protein located in the flagellar pocket.
creator: Sengupta, S
creator: Tripathi, J
creator: Tandon, R
creator: Raje, Manoj
creator: Roy, R P
creator: Basu, S K
creator: Mukhopadhyay, A
subject: QD Chemistry
description: Four lines of evidence indicate that a specific high affinity binding site on the surface of Leishmania donovani promastigotes mediates rapid internalization and degradation of hemoglobin. 1) Binding and uptake of 125I-hemoglobin by Leishmania followed saturation kinetics and were competed by unlabeled hemoglobin but not by globin or hemin or other heme- or iron-containing proteins. 2) Immunogold labeling studies revealed that, at 4 degreesC, hemoglobin binding was localized in the flagellar pocket of the promastigotes. Indirect immunofluorescence assays showed that, at 37 degreesC, the bound hemoglobin in such cells entered an endocytic compartment within 2 min and dispersed throughout the cell body by 15 min. 3) After incubation with hemoglobin-gold conjugates at 25 degreesC or 37 degreesC, the particles accumulated in discrete intracellular vesicles. 4) A single biotinylated protein of 46 kDa was revealed when solubilized membranes from surface biotinylated intact Leishmania adsorbed by hemoglobin-agarose beads were subjected to SDS-polyacrylamide gel electrophoresis and Western blotting with avidin-horseradish peroxidase. Considered together, these data indicate that this 46-kDa protein on the cell surface of L. donovani promastigotes mediates the binding of hemoglobin and its rapid internalization through a vesicular pathway characteristic of receptor-mediated endocytosis.
publisher: ASBMB
date: 1999-01-29
type: Article
type: PeerReviewed
format: application/pdf
identifier: http://crdd.osdd.net/open/793/1/basu1999.pdf
relation: http://www.jbc.org/content/274/5/2758.full.pdf+html
identifier:   Sengupta, S and Tripathi, J and Tandon, R and Raje, Manoj and Roy, R P and Basu, S K and Mukhopadhyay, A  (1999) Hemoglobin endocytosis in Leishmania is mediated through a 46-kDa protein located in the flagellar pocket.  The Journal of biological chemistry, 274 (5).  pp. 2758-65.  ISSN 0021-9258     
relation: http://crdd.osdd.net/open/793/