title: Clathrin-mediated hemoglobin endocytosis is essential for survival of Leishmania.
abstract: Leishmania is auxotroph for heme. Previously, we have shown that Leishmania acquire heme from the degradation of endocytosed hemoglobin via a specific receptor located in the flagellar pocket. Here, we report the cloning and expression of clathrin heavy chain from Leishmania (Ld-CHC) and provide evidences that Ld-CHC is localized in flagellar pocket and regulates Hb-endocytosis in Leishmania. Kinetic analysis of Hb trafficking in GFP-Ld-CHC overexpressed Leishmania reveals that Hb is internalized through Ld-CHC coated region and remains associated with Ld-CHC containing vesicles at early time points of internalization and subsequently starts dissociating from Hb-containing vesicles at later time points indicating that clathrin-coating and uncoating regulate Hb trafficking in Leishmania. Interestingly, overexpression of dominant negative mutant of clathrin heavy chain of Leishmania (GFP-Ld-CHC-Hub) blocks the Hb internalization and causes severe growth defect in parasite. Moreover, we have shown that chlorpromazine, a pharmacological agent, blocks Hb internalization in Leishmania by depolymerizing Ld-CHC and thereby inhibits the growth of the parasites. Taken together, our results have shown that Hb endocytosis in Leishmania is a clathrin dependent process and is essential for the survival of the parasites.
authors: National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, India.
authors: Shruti
authors: S
authors: Agarwal
authors: Ruchir
authors: R
authors: Rastogi
authors: Deepika
authors: D
authors: Gupta
authors: Nitin
authors: N
authors: Patel
authors: Manoj
authors: M
authors: Raje
authors: Amitabha
authors: A
authors: Mukhopadhyay
mesh_terms: D000595:Amino Acid Sequence; D002746:Chlorpromazine / Q000494:pharmacology; D033922:Clathrin Heavy Chains / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D004705:Endocytosis / Q000187:drug effects / Q000235:genetics; D015870:Gene Expression / Q000187:drug effects; D006418:Heme / Q000378:metabolism; D006454:Hemoglobins / Q000378:metabolism; D007700:Kinetics; D007891:Leishmania / Q000235:genetics / Q000378:metabolism / Q000469:parasitology; D008969:Molecular Sequence Data
chemical_list: D006454:Hemoglobins; D033922:Clathrin Heavy Chains; D006418:Heme; D002746:Chlorpromazine