title: Two members of the beige/CHS (BEACH) family are involved at different stages in the organization of the endocytic pathway in Dictyostelium.
abstract: Proteins of the Chediak-Higashi/Beige (BEACH) family have been implicated in the function of lysosomes, as well as in signal transduction, but their molecular role is still poorly understood. In Dictyostelium, at least six members of the family can be identified. Here cells with mutations in two of these genes, LVSA and LVSB, were analyzed. Interestingly both mutants exhibited defects in the organization of the endocytic pathway, albeit at distinct stages. In lvsB mutant cells, the regulated secretion of lysosomal enzymes was enhanced, a phenotype reminiscent of the Chediak-Higashi syndrome. LvsA mutant cells exhibited alterations in the organization and function of the early endocytic and phagocytic pathway. The LvsA protein may participate in the signaling pathway, which links adhesion of a particle to the subsequent formation of a phagocytic cup. Further genetic analysis will be necessary to determine whether other members of the BEACH family of proteins are also involved in controlling the organization of the endocytic pathway.
authors.affiliation: Université de Genève, Centre Médical Universitaire, Département de morphologie, 1 Rue Michel Servet, CH1211 Genève 4, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: Cornillon
authors.forename: Annick
authors.initials: A
authors.lastname: Dubois
authors.forename: Franz
authors.initials: F
authors.lastname: Brückert
authors.forename: Yaya
authors.initials: Y
authors.lastname: Lefkir
authors.forename: Anna
authors.initials: A
authors.lastname: Marchetti
authors.forename: Mohammed
authors.initials: M
authors.lastname: Benghezal
authors.forename: Arturo
authors.initials: A
authors.lastname: De Lozanne
authors.forename: François
authors.initials: F
authors.lastname: Letourneur
authors.forename: Pierre
authors.initials: P
authors.lastname: Cosson
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D004023:Dictyostelium / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D004705:Endocytosis; D007700:Kinetics; D008247:Lysosomes / Q000201:enzymology; D009154:Mutation; D010587:Phagocytosis; D010588:Phagosomes / Q000201:enzymology / Q000648:ultrastructure; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D025262:Vacuolar Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism
chemical_list: C403705:LvsA protein, Dictyostelium; D011506:Proteins; D015800:Protozoan Proteins; D025262:Vacuolar Proton-Translocating ATPases