A centriolar FGR1 oncogene partner-like protein required for paraflagellar rod assembly, but not axoneme assembly in African trypanosomes.

摘要: Proteins of the FGR1 oncogene partner (or FOP) family are found at microtubule organizing centres (MTOCs) including, in flagellate eukaryotes, centriole or flagellar basal body from which axoneme extends. We report conservation FOP proteins, TbFOPL and TbOFD1, evolutionarily divergent sleeping sickness parasite Trypanosoma brucei, showing (in contrast with mammalian cells, where is essential for flagellum assembly) depletion a trypanosome homologue, TbFOPL, affects neither nor elongation. Instead, causes catastrophic failure assembly lineage-specific, extra-axonemal structure, paraflagellar rod (PFR). That centriolar PFR surprising because nucleation commences approximately 2 µm distal body. When over-expressed C-terminal myc-epitope, was also observed mitotic spindle poles. Little known about bi-polar during closed mitosis, but indication possible additional MTOC function parallels localization FOP-like protein TONNEAU1 acentriolar plants. More generally, our functional analysis emphasizes significant differences evolutionary cell biology trajectories FOP-family proteins. discuss how molecular level homologues may contribute to diverse flagellates.