Modes of flagellar assembly in Chlamydomonas reinhardtii and Trypanosoma brucei.
Defects in flagella growth are related to a number of human diseases. Central to flagellar growth is the organization of microtubules that polymerize from basal bodies to form the axoneme, which consists of hundreds of proteins. Flagella exist in all eukaryotic phyla, but neither the mechanism by which flagella grow nor the conservation of this process in evolution are known. Here, we study how protein complexes assemble onto the growing axoneme tip using (cryo) electron tomography. In Chlamydomonas reinhardtii microtubules and associated proteins are added simultaneously. However, in Trypanosoma brucei, disorganized arrays of microtubules are arranged into the axoneme structure by the later addition of preformed protein complexes. Post assembly, the T. brucei transition zone alters structure and its association with the central pair loosens. We conclude that there are multiple ways to form a flagellum and that species-specific structural knowledge is critical before evaluating flagellar defects. DOI: http://dx.doi.org/10.7554/eLife.01479.001.
Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.
Johanna L
JL
Höög
Sylvain
S
Lacomble
Eileen T
ET
O'Toole
Andreas
A
Hoenger
J Richard
JR
McIntosh
Keith
K
Gull
D020418:Algal Proteins / Q000378:metabolism; D054468:Axoneme / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D016825:Chlamydomonas reinhardtii / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure; D020285:Cryoelectron Microscopy; D005407:Flagella / Q000378:metabolism / Q000502:physiology* / Q000648:ultrastructure; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D015800:Protozoan Proteins / Q000378:metabolism; D013045:Species Specificity; D014346:Trypanosoma brucei brucei / Q000254:growth & development* / Q000378:metabolism / Q000648:ultrastructure
D020418:Algal Proteins; D008869:Microtubule-Associated Proteins; D015800:Protozoan Proteins
Chlamydomonas reinhardtii; Trypanosoma brucei; axoneme; electron tomography; flagellum; microtubule