title: A coiled-coil- and C2-domain-containing protein is required for FAZ assembly and cell morphology in Trypanosoma brucei.
abstract: Trypanosoma brucei, a flagellated protozoan parasite causing human sleeping sickness, relies on a subpellicular microtubule array for maintenance of cell morphology. The flagellum is attached to the cell body through a poorly understood flagellum attachment zone (FAZ), and regulates cell morphogenesis using an unknown mechanism. Here we identified a new FAZ component, CC2D, which contains coiled-coil motifs followed by a C-terminal C2 domain. T. brucei CC2D is present on the FAZ filament, FAZ-juxtaposed ER membrane and the basal bodies. Depletion of CC2D inhibits the assembly of a new FAZ filament, forming a FAZ stub with a relatively fixed size at the base of a detached, but otherwise normal, flagellum. Inhibition of new FAZ formation perturbs subpellicular microtubule organization and generates short daughter cells. The cell length shows a strong linear correlation with FAZ length, in both control cells and in cells with inhibited FAZ assembly. Together, our data support a direct function of FAZ assembly in determining new daughter cell length by regulating subpellicular microtubule synthesis.
authors: Department of Biological Sciences, National University of Singapore,  Singapore 117543.
authors: Qing
authors: Q
authors: Zhou
authors: Binghai
authors: B
authors: Liu
authors: Ying
authors: Y
authors: Sun
authors: Cynthia Y
authors: CY
authors: He
mesh_terms: D002455:Cell Division; D005407:Flagella / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009024:Morphogenesis; D017434:Protein Structure, Tertiary; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014346:Trypanosoma brucei brucei / Q000166:cytology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*
chemical_list: D015800:Protozoan Proteins