@article{open793,
          volume = {274},
          number = {5},
           month = {January},
          author = {S Sengupta and J Tripathi and R Tandon and Manoj Raje and R P Roy and S K Basu and A Mukhopadhyay},
            note = {Copyright of this article belongs to ASBMB.},
           title = {Hemoglobin endocytosis in Leishmania is mediated through a 46-kDa protein located in the flagellar pocket.},
       publisher = {ASBMB},
            year = {1999},
         journal = {The Journal of biological chemistry},
           pages = {2758--65},
             url = {http://crdd.osdd.net/open/793/},
        abstract = {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.}
}